Fixed typo

OneDrive: list folder issue fixed, removed escape symbols in path

.travis.yml

@@ -12,8 +12,8 @@ env:
   - MACOS_SDK=macosx
   - TVOS_SDK=appletvsimulator
   matrix:
-    - DESTINATION="OS=10.2,name=iPad Air 2"        SCHEME="$IOS_FRAMEWORK_SCHEME"     SDK="$IOS_SDK"     RUN_TESTS="NO" BUILD_EXAMPLE="NO" POD="YES" CARTHAGEDEPLOY="NO"
-    - DESTINATION="OS=9.0,name=iPhone 6"           SCHEME="$IOS_FRAMEWORK_SCHEME"     SDK="$IOS_SDK"     RUN_TESTS="NO" BUILD_EXAMPLE="NO" POD="NO"  CARTHAGEDEPLOY="YES"
+    - DESTINATION="OS=10.2,name=iPad Air 2"        SCHEME="$IOS_FRAMEWORK_SCHEME"     SDK="$IOS_SDK"     RUN_TESTS="NO" BUILD_EXAMPLE="NO" POD="NO" CARTHAGEDEPLOY="YES"
+    - DESTINATION="OS=9.0,name=iPhone 6"           SCHEME="$IOS_FRAMEWORK_SCHEME"     SDK="$IOS_SDK"     RUN_TESTS="NO" BUILD_EXAMPLE="NO" POD="YES"  CARTHAGEDEPLOY="NO"
     - DESTINATION="OS=8.1,name=iPhone 4S"          SCHEME="$IOS_FRAMEWORK_SCHEME"     SDK="$IOS_SDK"     RUN_TESTS="NO" BUILD_EXAMPLE="NO" POD="NO"  CARTHAGEDEPLOY="NO"
 
     - DESTINATION="OS=10.1,name=Apple TV 1080p"    SCHEME="$TVOS_FRAMEWORK_SCHEME"    SDK="$TVOS_SDK"    RUN_TESTS="NO" BUILD_EXAMPLE="NO" POD="NO"  CARTHAGEDEPLOY="NO"
@@ -56,7 +56,7 @@ script:
 after_success:
   # Run `pod trunk push` if specified
   - if [ $POD == "YES" ] && [ -n "$TRAVIS_TAG" ]; then
-      pod trunk push;
+      pod trunk push --allow-warnings;
     fi
 
 #   - bash <(curl -s https://codecov.io/bash)
@@ -75,6 +75,7 @@ deploy:
   file: $FRAMEWORK_NAME.zip
   skip_cleanup: true
   on:
-    repo: amosavian/$PROJECTNAME
+    # repo: amosavian/$PROJECTNAME
+    repo: amosavian/FileProvider
     tags: true
     condition: "$CARTHAGEDEPLOY = YES"

FilesProvider.podspec

@@ -1,5 +1,5 @@
 #
-#  Be sure to run `pod spec lint FileProvider.podspec' to ensure this is a
+#  Be sure to run `pod spec lint FilesProvider.podspec' to ensure this is a
 #  valid spec and to remove all comments including this before submitting the spec.
 #
 #  To learn more about Podspec attributes see http://docs.cocoapods.org/specification.html
@@ -15,9 +15,9 @@ Pod::Spec.new do |s|
   #  summary should be tweet-length, and the description more in depth.
   #
 
-  s.name         = "FileProvider"
-  s.version      = "0.14.5"
-  s.summary      = "FileManager replacement for Local and Remote (WebDAV/Dropbox/OneDrive/SMB2) files on iOS and macOS."
+  s.name         = "FilesProvider"
+  s.version      = "0.19.0"
+  s.summary      = "FileManager replacement for Local and Remote (WebDAV/FTP/Dropbox/OneDrive/SMB2) files on iOS and macOS."
 
   # This description is used to generate tags and improve search results.
   #   * Think: What does it do? Why did you write it? What is the focus?

FilesProvider.xcodeproj/project.pbxproj

@@ -35,6 +35,9 @@
 		792572411DF23BDA006A1526 /* LocalHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 792572401DF23BDA006A1526 /* LocalHelper.swift */; };
 		792572421DF23BDA006A1526 /* LocalHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 792572401DF23BDA006A1526 /* LocalHelper.swift */; };
 		792572431DF23BDA006A1526 /* LocalHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 792572401DF23BDA006A1526 /* LocalHelper.swift */; };
+		7936BC121E880F5700A6C81C /* FTPFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7936BC111E880F5700A6C81C /* FTPFileProvider.swift */; };
+		7936BC131E880F5700A6C81C /* FTPFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7936BC111E880F5700A6C81C /* FTPFileProvider.swift */; };
+		7936BC141E880F5700A6C81C /* FTPFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7936BC111E880F5700A6C81C /* FTPFileProvider.swift */; };
 		79480FF61E3ABDD0007E7275 /* CloudFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79480FF51E3ABDD0007E7275 /* CloudFileProvider.swift */; };
 		79480FF71E3ABDD0007E7275 /* CloudFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79480FF51E3ABDD0007E7275 /* CloudFileProvider.swift */; };
 		79480FF81E3ABDD0007E7275 /* CloudFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79480FF51E3ABDD0007E7275 /* CloudFileProvider.swift */; };
@@ -50,6 +53,7 @@
 		796807551E7BF17E00BBB87B /* FileProviderExtensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 796807541E7BF17E00BBB87B /* FileProviderExtensions.swift */; };
 		796807561E7BF17E00BBB87B /* FileProviderExtensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 796807541E7BF17E00BBB87B /* FileProviderExtensions.swift */; };
 		796807571E7BF17E00BBB87B /* FileProviderExtensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 796807541E7BF17E00BBB87B /* FileProviderExtensions.swift */; };
+		798654331E8874BC002FA550 /* FTPHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 798654321E8874BC002FA550 /* FTPHelper.swift */; };
 		799396AA1D48C02300086753 /* DropboxFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 799396931D48C02300086753 /* DropboxFileProvider.swift */; };
 		799396AB1D48C02300086753 /* DropboxFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 799396931D48C02300086753 /* DropboxFileProvider.swift */; };
 		799396AC1D48C02300086753 /* DropboxFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 799396931D48C02300086753 /* DropboxFileProvider.swift */; };
@@ -112,12 +116,14 @@
 		79BD63BE1E2CC3C20035128C /* ImageIO.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 79BD63BD1E2CC3C20035128C /* ImageIO.framework */; };
 		79BD63C01E2CC3CD0035128C /* CoreGraphics.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 79BD63BF1E2CC3CD0035128C /* CoreGraphics.framework */; };
 		79BD63C21E2CC3D30035128C /* AVFoundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 79BD63C11E2CC3D30035128C /* AVFoundation.framework */; };
-		79BD63C51E2D17880035128C /* OneDriveFileProvide.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C31E2D17880035128C /* OneDriveFileProvide.swift */; };
-		79BD63C61E2D17880035128C /* OneDriveFileProvide.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C31E2D17880035128C /* OneDriveFileProvide.swift */; };
-		79BD63C71E2D17880035128C /* OneDriveFileProvide.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C31E2D17880035128C /* OneDriveFileProvide.swift */; };
+		79BD63C51E2D17880035128C /* OneDriveFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C31E2D17880035128C /* OneDriveFileProvider.swift */; };
+		79BD63C61E2D17880035128C /* OneDriveFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C31E2D17880035128C /* OneDriveFileProvider.swift */; };
+		79BD63C71E2D17880035128C /* OneDriveFileProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C31E2D17880035128C /* OneDriveFileProvider.swift */; };
 		79BD63C81E2D17880035128C /* OneDriveHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C41E2D17880035128C /* OneDriveHelper.swift */; };
 		79BD63C91E2D17880035128C /* OneDriveHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C41E2D17880035128C /* OneDriveHelper.swift */; };
 		79BD63CA1E2D17880035128C /* OneDriveHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79BD63C41E2D17880035128C /* OneDriveHelper.swift */; };
+		79F4678B1E8B80F200C91A85 /* FTPHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 798654321E8874BC002FA550 /* FTPHelper.swift */; };
+		79F4678C1E8B80F200C91A85 /* FTPHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 798654321E8874BC002FA550 /* FTPHelper.swift */; };
 		79F5745B1DFDB10B00179ABF /* FileObject.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79F5745A1DFDB10A00179ABF /* FileObject.swift */; };
 		79F5745C1DFDB10B00179ABF /* FileObject.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79F5745A1DFDB10A00179ABF /* FileObject.swift */; };
 		79F5745D1DFDB10B00179ABF /* FileObject.swift in Sources */ = {isa = PBXBuildFile; fileRef = 79F5745A1DFDB10A00179ABF /* FileObject.swift */; };
@@ -133,14 +139,16 @@
 		7924B1921D89DAE000589DB7 /* Parser.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Parser.swift; sourceTree = "<group>"; };
 		7924B1A81D89F79200589DB7 /* FPSStreamTask.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FPSStreamTask.swift; sourceTree = "<group>"; };
 		792572401DF23BDA006A1526 /* LocalHelper.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = LocalHelper.swift; sourceTree = "<group>"; };
+		7936BC111E880F5700A6C81C /* FTPFileProvider.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FTPFileProvider.swift; sourceTree = "<group>"; };
 		79480FF51E3ABDD0007E7275 /* CloudFileProvider.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CloudFileProvider.swift; sourceTree = "<group>"; };
 		794C21FD1D58912A00EC49B8 /* DropboxHelper.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DropboxHelper.swift; sourceTree = "<group>"; };
 		794C22091D5893F800EC49B8 /* SMB2Notification.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SMB2Notification.swift; sourceTree = "<group>"; };
 		794C220D1D591A4B00EC49B8 /* SMB2QueryTypes.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SMB2QueryTypes.swift; sourceTree = "<group>"; };
 		796807541E7BF17E00BBB87B /* FileProviderExtensions.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FileProviderExtensions.swift; sourceTree = "<group>"; };
-		799396671D48B7F600086753 /* FileProvider.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FileProvider.framework; sourceTree = BUILT_PRODUCTS_DIR; };
-		799396751D48B80D00086753 /* FileProvider.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FileProvider.framework; sourceTree = BUILT_PRODUCTS_DIR; };
-		799396821D48B82700086753 /* FileProvider.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FileProvider.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		798654321E8874BC002FA550 /* FTPHelper.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FTPHelper.swift; sourceTree = "<group>"; };
+		799396671D48B7F600086753 /* FilesProvider.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FilesProvider.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		799396751D48B80D00086753 /* FilesProvider.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FilesProvider.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		799396821D48B82700086753 /* FilesProvider.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FilesProvider.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		7993968B1D48B8C700086753 /* Info-iOS.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = "Info-iOS.plist"; sourceTree = "<group>"; };
 		7993968C1D48B8C700086753 /* Info-MacOS.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = "Info-MacOS.plist"; sourceTree = "<group>"; };
 		7993968D1D48B8C700086753 /* Info-tvOS.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = "Info-tvOS.plist"; sourceTree = "<group>"; };
@@ -174,7 +182,7 @@
 		79BD63BD1E2CC3C20035128C /* ImageIO.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = ImageIO.framework; path = Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS10.1.sdk/System/Library/Frameworks/ImageIO.framework; sourceTree = DEVELOPER_DIR; };
 		79BD63BF1E2CC3CD0035128C /* CoreGraphics.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreGraphics.framework; path = Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS10.1.sdk/System/Library/Frameworks/CoreGraphics.framework; sourceTree = DEVELOPER_DIR; };
 		79BD63C11E2CC3D30035128C /* AVFoundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = AVFoundation.framework; path = Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS10.1.sdk/System/Library/Frameworks/AVFoundation.framework; sourceTree = DEVELOPER_DIR; };
-		79BD63C31E2D17880035128C /* OneDriveFileProvide.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = OneDriveFileProvide.swift; sourceTree = "<group>"; };
+		79BD63C31E2D17880035128C /* OneDriveFileProvider.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = OneDriveFileProvider.swift; sourceTree = "<group>"; };
 		79BD63C41E2D17880035128C /* OneDriveHelper.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = OneDriveHelper.swift; sourceTree = "<group>"; };
 		79F5745A1DFDB10A00179ABF /* FileObject.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FileObject.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
@@ -261,9 +269,9 @@
 		799396681D48B7F600086753 /* Products */ = {
 			isa = PBXGroup;
 			children = (
-				799396671D48B7F600086753 /* FileProvider.framework */,
-				799396751D48B80D00086753 /* FileProvider.framework */,
-				799396821D48B82700086753 /* FileProvider.framework */,
+				799396671D48B7F600086753 /* FilesProvider.framework */,
+				799396751D48B80D00086753 /* FilesProvider.framework */,
+				799396821D48B82700086753 /* FilesProvider.framework */,
 			);
 			name = Products;
 			sourceTree = "<group>";
@@ -294,7 +302,9 @@
 				7902C0851D61B56D00564440 /* RemoteSession.swift */,
 				799396931D48C02300086753 /* DropboxFileProvider.swift */,
 				794C21FD1D58912A00EC49B8 /* DropboxHelper.swift */,
-				79BD63C31E2D17880035128C /* OneDriveFileProvide.swift */,
+				7936BC111E880F5700A6C81C /* FTPFileProvider.swift */,
+				798654321E8874BC002FA550 /* FTPHelper.swift */,
+				79BD63C31E2D17880035128C /* OneDriveFileProvider.swift */,
 				79BD63C41E2D17880035128C /* OneDriveHelper.swift */,
 				7924B1A81D89F79200589DB7 /* FPSStreamTask.swift */,
 				799396971D48C02300086753 /* SMBClient.swift */,
@@ -358,9 +368,9 @@
 /* End PBXHeadersBuildPhase section */
 
 /* Begin PBXNativeTarget section */
-		799396661D48B7F600086753 /* FileProvider iOS */ = {
+		799396661D48B7F600086753 /* FilesProvider iOS */ = {
 			isa = PBXNativeTarget;
-			buildConfigurationList = 7993966F1D48B7F600086753 /* Build configuration list for PBXNativeTarget "FileProvider iOS" */;
+			buildConfigurationList = 7993966F1D48B7F600086753 /* Build configuration list for PBXNativeTarget "FilesProvider iOS" */;
 			buildPhases = (
 				799396621D48B7F600086753 /* Sources */,
 				799396631D48B7F600086753 /* Frameworks */,
@@ -371,14 +381,14 @@
 			);
 			dependencies = (
 			);
-			name = "FileProvider iOS";
+			name = "FilesProvider iOS";
 			productName = "FileProvider iOS";
-			productReference = 799396671D48B7F600086753 /* FileProvider.framework */;
+			productReference = 799396671D48B7F600086753 /* FilesProvider.framework */;
 			productType = "com.apple.product-type.framework";
 		};
-		799396741D48B80D00086753 /* FileProvider OSX */ = {
+		799396741D48B80D00086753 /* FilesProvider OSX */ = {
 			isa = PBXNativeTarget;
-			buildConfigurationList = 7993967A1D48B80D00086753 /* Build configuration list for PBXNativeTarget "FileProvider OSX" */;
+			buildConfigurationList = 7993967A1D48B80D00086753 /* Build configuration list for PBXNativeTarget "FilesProvider OSX" */;
 			buildPhases = (
 				799396701D48B80D00086753 /* Sources */,
 				799396711D48B80D00086753 /* Frameworks */,
@@ -389,14 +399,14 @@
 			);
 			dependencies = (
 			);
-			name = "FileProvider OSX";
+			name = "FilesProvider OSX";
 			productName = "FileProvider OSX";
-			productReference = 799396751D48B80D00086753 /* FileProvider.framework */;
+			productReference = 799396751D48B80D00086753 /* FilesProvider.framework */;
 			productType = "com.apple.product-type.framework";
 		};
-		799396811D48B82700086753 /* FileProvider tvOS */ = {
+		799396811D48B82700086753 /* FilesProvider tvOS */ = {
 			isa = PBXNativeTarget;
-			buildConfigurationList = 799396871D48B82700086753 /* Build configuration list for PBXNativeTarget "FileProvider tvOS" */;
+			buildConfigurationList = 799396871D48B82700086753 /* Build configuration list for PBXNativeTarget "FilesProvider tvOS" */;
 			buildPhases = (
 				7993967D1D48B82700086753 /* Sources */,
 				7993967E1D48B82700086753 /* Frameworks */,
@@ -407,9 +417,9 @@
 			);
 			dependencies = (
 			);
-			name = "FileProvider tvOS";
+			name = "FilesProvider tvOS";
 			productName = "FileProvider tvOS";
-			productReference = 799396821D48B82700086753 /* FileProvider.framework */;
+			productReference = 799396821D48B82700086753 /* FilesProvider.framework */;
 			productType = "com.apple.product-type.framework";
 		};
 /* End PBXNativeTarget section */
@@ -432,7 +442,7 @@
 					};
 				};
 			};
-			buildConfigurationList = 7993965F1D48B7BF00086753 /* Build configuration list for PBXProject "FileProvider" */;
+			buildConfigurationList = 7993965F1D48B7BF00086753 /* Build configuration list for PBXProject "FilesProvider" */;
 			compatibilityVersion = "Xcode 3.2";
 			developmentRegion = English;
 			hasScannedForEncodings = 0;
@@ -444,9 +454,9 @@
 			projectDirPath = "";
 			projectRoot = "";
 			targets = (
-				799396661D48B7F600086753 /* FileProvider iOS */,
-				799396741D48B80D00086753 /* FileProvider OSX */,
-				799396811D48B82700086753 /* FileProvider tvOS */,
+				799396661D48B7F600086753 /* FilesProvider iOS */,
+				799396741D48B80D00086753 /* FilesProvider OSX */,
+				799396811D48B82700086753 /* FilesProvider tvOS */,
 			);
 		};
 /* End PBXProject section */
@@ -485,12 +495,14 @@
 				799396D41D48C02300086753 /* SMB2Tree.swift in Sources */,
 				7924B1A21D89DAE000589DB7 /* Options.swift in Sources */,
 				792572411DF23BDA006A1526 /* LocalHelper.swift in Sources */,
+				7936BC121E880F5700A6C81C /* FTPFileProvider.swift in Sources */,
 				79480FF61E3ABDD0007E7275 /* CloudFileProvider.swift in Sources */,
 				79F5745B1DFDB10B00179ABF /* FileObject.swift in Sources */,
-				79BD63C51E2D17880035128C /* OneDriveFileProvide.swift in Sources */,
+				79BD63C51E2D17880035128C /* OneDriveFileProvider.swift in Sources */,
 				7924B1991D89DAE000589DB7 /* Element.swift in Sources */,
 				799396C81D48C02300086753 /* SMB2IOCtl.swift in Sources */,
 				799396D71D48C02300086753 /* SMB2Types.swift in Sources */,
+				798654331E8874BC002FA550 /* FTPHelper.swift in Sources */,
 				7924B1B21D89FCDA00589DB7 /* FPSStreamTask.swift in Sources */,
 				799396C51D48C02300086753 /* SMB2FileOperation.swift in Sources */,
 				79BD63C81E2D17880035128C /* OneDriveHelper.swift in Sources */,
@@ -526,12 +538,14 @@
 				799396D51D48C02300086753 /* SMB2Tree.swift in Sources */,
 				7924B1A31D89DAE000589DB7 /* Options.swift in Sources */,
 				792572421DF23BDA006A1526 /* LocalHelper.swift in Sources */,
+				7936BC131E880F5700A6C81C /* FTPFileProvider.swift in Sources */,
 				79480FF71E3ABDD0007E7275 /* CloudFileProvider.swift in Sources */,
 				79F5745C1DFDB10B00179ABF /* FileObject.swift in Sources */,
-				79BD63C61E2D17880035128C /* OneDriveFileProvide.swift in Sources */,
+				79BD63C61E2D17880035128C /* OneDriveFileProvider.swift in Sources */,
 				7924B1B01D89F7DE00589DB7 /* FPSStreamTask.swift in Sources */,
 				7924B19A1D89DAE000589DB7 /* Element.swift in Sources */,
 				799396C91D48C02300086753 /* SMB2IOCtl.swift in Sources */,
+				79F4678B1E8B80F200C91A85 /* FTPHelper.swift in Sources */,
 				799396D81D48C02300086753 /* SMB2Types.swift in Sources */,
 				799396C61D48C02300086753 /* SMB2FileOperation.swift in Sources */,
 				79BD63C91E2D17880035128C /* OneDriveHelper.swift in Sources */,
@@ -567,12 +581,14 @@
 				799396D61D48C02300086753 /* SMB2Tree.swift in Sources */,
 				7924B1A41D89DAE000589DB7 /* Options.swift in Sources */,
 				792572431DF23BDA006A1526 /* LocalHelper.swift in Sources */,
+				7936BC141E880F5700A6C81C /* FTPFileProvider.swift in Sources */,
 				79480FF81E3ABDD0007E7275 /* CloudFileProvider.swift in Sources */,
 				79F5745D1DFDB10B00179ABF /* FileObject.swift in Sources */,
-				79BD63C71E2D17880035128C /* OneDriveFileProvide.swift in Sources */,
+				79BD63C71E2D17880035128C /* OneDriveFileProvider.swift in Sources */,
 				7924B1B11D89F7DF00589DB7 /* FPSStreamTask.swift in Sources */,
 				7924B19B1D89DAE000589DB7 /* Element.swift in Sources */,
 				799396CA1D48C02300086753 /* SMB2IOCtl.swift in Sources */,
+				79F4678C1E8B80F200C91A85 /* FTPHelper.swift in Sources */,
 				799396D91D48C02300086753 /* SMB2Types.swift in Sources */,
 				799396C71D48C02300086753 /* SMB2FileOperation.swift in Sources */,
 				79BD63CA1E2D17880035128C /* OneDriveHelper.swift in Sources */,
@@ -605,7 +621,7 @@
 		799396601D48B7BF00086753 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				BUNDLE_VERSION_STRING = 0.14.5;
+				BUNDLE_VERSION_STRING = 0.19.0;
 				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_EMPTY_BODY = YES;
@@ -615,6 +631,7 @@
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
 				CLANG_WARN_UNREACHABLE_CODE = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				COPY_PHASE_STRIP = NO;
 				DEBUG_INFORMATION_FORMAT = dwarf;
 				ENABLE_BITCODE = YES;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
@@ -628,6 +645,7 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				ONLY_ACTIVE_ARCH = YES;
+				PRODUCT_NAME = FilesProvider;
 				SWIFT_VERSION = 3.0;
 			};
 			name = Debug;
@@ -635,7 +653,7 @@
 		799396611D48B7BF00086753 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				BUNDLE_VERSION_STRING = 0.14.5;
+				BUNDLE_VERSION_STRING = 0.19.0;
 				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
 				CLANG_WARN_EMPTY_BODY = YES;
@@ -655,6 +673,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
+				PRODUCT_NAME = FilesProvider;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				SWIFT_VERSION = 3.0;
 			};
@@ -701,8 +720,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MTL_ENABLE_DEBUG_INFO = YES;
-				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FileProvider-iOS";
-				PRODUCT_NAME = FileProvider;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FilesProvider-iOS";
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -748,8 +766,7 @@
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MTL_ENABLE_DEBUG_INFO = NO;
-				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FileProvider-iOS";
-				PRODUCT_NAME = FileProvider;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FilesProvider-iOS";
 				SDKROOT = iphoneos;
 				SKIP_INSTALL = YES;
 				TARGETED_DEVICE_FAMILY = "1,2";
@@ -805,8 +822,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.10;
 				MTL_ENABLE_DEBUG_INFO = YES;
-				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FileProvider-OSX";
-				PRODUCT_NAME = FileProvider;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FilesProvider-OSX";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -856,8 +872,7 @@
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/../Frameworks @loader_path/Frameworks";
 				MACOSX_DEPLOYMENT_TARGET = 10.10;
 				MTL_ENABLE_DEBUG_INFO = NO;
-				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FileProvider-OSX";
-				PRODUCT_NAME = FileProvider;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FilesProvider-OSX";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
 				VERSIONING_SYSTEM = "apple-generic";
@@ -908,8 +923,7 @@
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MTL_ENABLE_DEBUG_INFO = YES;
-				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FileProvider-tvOS";
-				PRODUCT_NAME = FileProvider;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FilesProvider-tvOS";
 				SDKROOT = appletvos;
 				SKIP_INSTALL = YES;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
@@ -958,8 +972,7 @@
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks @loader_path/Frameworks";
 				MTL_ENABLE_DEBUG_INFO = NO;
-				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FileProvider-tvOS";
-				PRODUCT_NAME = FileProvider;
+				PRODUCT_BUNDLE_IDENTIFIER = "com.mousavian.FilesProvider-tvOS";
 				SDKROOT = appletvos;
 				SKIP_INSTALL = YES;
 				TARGETED_DEVICE_FAMILY = 3;
@@ -973,7 +986,7 @@
 /* End XCBuildConfiguration section */
 
 /* Begin XCConfigurationList section */
-		7993965F1D48B7BF00086753 /* Build configuration list for PBXProject "FileProvider" */ = {
+		7993965F1D48B7BF00086753 /* Build configuration list for PBXProject "FilesProvider" */ = {
 			isa = XCConfigurationList;
 			buildConfigurations = (
 				799396601D48B7BF00086753 /* Debug */,
@@ -982,7 +995,7 @@
 			defaultConfigurationIsVisible = 0;
 			defaultConfigurationName = Release;
 		};
-		7993966F1D48B7F600086753 /* Build configuration list for PBXNativeTarget "FileProvider iOS" */ = {
+		7993966F1D48B7F600086753 /* Build configuration list for PBXNativeTarget "FilesProvider iOS" */ = {
 			isa = XCConfigurationList;
 			buildConfigurations = (
 				7993966D1D48B7F600086753 /* Debug */,
@@ -991,7 +1004,7 @@
 			defaultConfigurationIsVisible = 0;
 			defaultConfigurationName = Release;
 		};
-		7993967A1D48B80D00086753 /* Build configuration list for PBXNativeTarget "FileProvider OSX" */ = {
+		7993967A1D48B80D00086753 /* Build configuration list for PBXNativeTarget "FilesProvider OSX" */ = {
 			isa = XCConfigurationList;
 			buildConfigurations = (
 				7993967B1D48B80D00086753 /* Debug */,
@@ -1000,7 +1013,7 @@
 			defaultConfigurationIsVisible = 0;
 			defaultConfigurationName = Release;
 		};
-		799396871D48B82700086753 /* Build configuration list for PBXNativeTarget "FileProvider tvOS" */ = {
+		799396871D48B82700086753 /* Build configuration list for PBXNativeTarget "FilesProvider tvOS" */ = {
 			isa = XCConfigurationList;
 			buildConfigurations = (
 				799396881D48B82700086753 /* Debug */,

FilesProvider.xcodeproj/xcshareddata/xcschemes/FilesProvider OSX.xcscheme

@@ -15,9 +15,9 @@
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "799396741D48B80D00086753"
-               BuildableName = "FileProvider.framework"
-               BlueprintName = "FileProvider OSX"
-               ReferencedContainer = "container:FileProvider.xcodeproj">
+               BuildableName = "FilesProvider.framework"
+               BlueprintName = "FilesProvider OSX"
+               ReferencedContainer = "container:FilesProvider.xcodeproj">
             </BuildableReference>
          </BuildActionEntry>
       </BuildActionEntries>
@@ -26,6 +26,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
       </Testables>
@@ -36,6 +37,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
@@ -46,9 +48,9 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "799396741D48B80D00086753"
-            BuildableName = "FileProvider.framework"
-            BlueprintName = "FileProvider OSX"
-            ReferencedContainer = "container:FileProvider.xcodeproj">
+            BuildableName = "FilesProvider.framework"
+            BlueprintName = "FilesProvider OSX"
+            ReferencedContainer = "container:FilesProvider.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
       <AdditionalOptions>
@@ -64,9 +66,9 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "799396741D48B80D00086753"
-            BuildableName = "FileProvider.framework"
-            BlueprintName = "FileProvider OSX"
-            ReferencedContainer = "container:FileProvider.xcodeproj">
+            BuildableName = "FilesProvider.framework"
+            BlueprintName = "FilesProvider OSX"
+            ReferencedContainer = "container:FilesProvider.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
    </ProfileAction>

FilesProvider.xcodeproj/xcshareddata/xcschemes/FilesProvider iOS.xcscheme

@@ -15,9 +15,9 @@
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "799396661D48B7F600086753"
-               BuildableName = "FileProvider.framework"
-               BlueprintName = "FileProvider iOS"
-               ReferencedContainer = "container:FileProvider.xcodeproj">
+               BuildableName = "FilesProvider.framework"
+               BlueprintName = "FilesProvider iOS"
+               ReferencedContainer = "container:FilesProvider.xcodeproj">
             </BuildableReference>
          </BuildActionEntry>
       </BuildActionEntries>
@@ -26,6 +26,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
       </Testables>
@@ -36,6 +37,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
@@ -46,9 +48,9 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "799396661D48B7F600086753"
-            BuildableName = "FileProvider.framework"
-            BlueprintName = "FileProvider iOS"
-            ReferencedContainer = "container:FileProvider.xcodeproj">
+            BuildableName = "FilesProvider.framework"
+            BlueprintName = "FilesProvider iOS"
+            ReferencedContainer = "container:FilesProvider.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
       <AdditionalOptions>
@@ -64,9 +66,9 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "799396661D48B7F600086753"
-            BuildableName = "FileProvider.framework"
-            BlueprintName = "FileProvider iOS"
-            ReferencedContainer = "container:FileProvider.xcodeproj">
+            BuildableName = "FilesProvider.framework"
+            BlueprintName = "FilesProvider iOS"
+            ReferencedContainer = "container:FilesProvider.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
    </ProfileAction>

FilesProvider.xcodeproj/xcshareddata/xcschemes/FilesProvider tvOS.xcscheme

@@ -15,9 +15,9 @@
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "799396811D48B82700086753"
-               BuildableName = "FileProvider.framework"
-               BlueprintName = "FileProvider tvOS"
-               ReferencedContainer = "container:FileProvider.xcodeproj">
+               BuildableName = "FilesProvider.framework"
+               BlueprintName = "FilesProvider tvOS"
+               ReferencedContainer = "container:FilesProvider.xcodeproj">
             </BuildableReference>
          </BuildActionEntry>
       </BuildActionEntries>
@@ -26,6 +26,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
       </Testables>
@@ -36,6 +37,7 @@
       buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
       ignoresPersistentStateOnLaunch = "NO"
@@ -46,9 +48,9 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "799396811D48B82700086753"
-            BuildableName = "FileProvider.framework"
-            BlueprintName = "FileProvider tvOS"
-            ReferencedContainer = "container:FileProvider.xcodeproj">
+            BuildableName = "FilesProvider.framework"
+            BlueprintName = "FilesProvider tvOS"
+            ReferencedContainer = "container:FilesProvider.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
       <AdditionalOptions>
@@ -64,9 +66,9 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "799396811D48B82700086753"
-            BuildableName = "FileProvider.framework"
-            BlueprintName = "FileProvider tvOS"
-            ReferencedContainer = "container:FileProvider.xcodeproj">
+            BuildableName = "FilesProvider.framework"
+            BlueprintName = "FilesProvider tvOS"
+            ReferencedContainer = "container:FilesProvider.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
    </ProfileAction>

Package.swift

@@ -1,5 +1,5 @@
 import PackageDescription
 
 let package = Package(
-    name: "FileProvider"
-)
+    name: "FilesProvider"
+)

README.md

@@ -2,25 +2,32 @@
 
 >This Swift library provide a swifty way to deal with local and remote files and directories in a unified way.
 
+<center>
+
 [![Swift Version][swift-image]][swift-url]
 [![Platform][platform-image]](#)
 [![License][license-image]][license-url]
-
-[![Release versin][release-image]][release-url]
-[![CocoaPods version](https://img.shields.io/cocoapods/v/FileProvider.svg)][cocoapods]
-[![Carthage compatible][carthage-image]](https://github.com/Carthage/Carthage)
-
 [![Build Status][travis-image]][travis-url]
 [![Codebeat Badge][codebeat-image]][codebeat-url]
-[![Cocoapods Docs][docs-image]][docs-url]
+
+[![Release version][release-image]][release-url]
+[![CocoaPods version](https://img.shields.io/cocoapods/v/FilesProvider.svg)][cocoapods]
+[![Carthage compatible][carthage-image]](https://github.com/Carthage/Carthage)
 [![Cocoapods Downloads][cocoapods-downloads]][cocoapods]
 [![Cocoapods Apps][cocoapods-apps]][cocoapods]
 
+Old Cocoapods repo stats:
+[![Cocoapods Downloads][cocoapods-downloads-old]][cocoapods-old]
+[![Cocoapods Apps][cocoapods-apps-old]][cocoapods-old]
+
+</center>
+
 <!--- 
+[![Cocoapods Doc][docs-image]][docs-url]
 [![codecov](https://codecov.io/gh/amosavian/FileProvider/branch/master/graph/badge.svg)](https://codecov.io/gh/amosavian/FileProvider) 
 ---> 
 
-This library provides implementaion of WebDav, Dropbox, OneDrive and SMB2 (incomplete) and local files.
+This library provides implementaion of WebDav, FTP, Dropbox, OneDrive and SMB2 (incomplete) and local files.
 
 All functions do async calls and it wont block your main thread.
 
@@ -28,7 +35,8 @@ All functions do async calls and it wont block your main thread.
 
 - [x] **LocalFileProvider** a wrapper around `FileManager` with some additions like builtin coordinating, searching and reading a portion of file.
 - [x] **CloudFileProvider** A wrapper around app's ubiquitous container API of iCloud Drive.
-- [x] **WebDAVFileProvider** WebDAV protocol is defacto file transmission standard, used by many cloud services like Yandex.
+- [x] **WebDAVFileProvider** WebDAV protocol is defacto file transmission standard, supported by some cloud services like `ownCloud`, `Box.com` and `Yandex.disk`.
+- [x] **FTPFileProvider** While deprecated in 1990s due to serious security concerns, it's still in use on some Web hosts.
 - [x] **DropboxFileProvider** A wrapper around Dropbox Web API.
     * For now it has limitation in uploading files up to 150MB.
 - [x] **OneDriveFileProvider** A wrapper around OneDrive REST API, works with `onedrive.com` and compatible (business) servers.
@@ -37,25 +45,27 @@ All functions do async calls and it wont block your main thread.
 - [ ] **AmazonS3FileProvider** Amazon storage backend. Used by many sites.
 - [ ] **SMBFileProvider** SMB2/3 introduced in 2006, which is a file and printer sharing protocol originated from Microsoft Windows and now is replacing AFP protocol on macOS.
     * Data types and some basic functions are implemented but *main interface is not implemented yet!*.
-    * SMB1/CIFS is deprecated and very tricky to be implemented.
-- [ ] **FTPFileProvider** while deprecated in 1990s, it's still in use on some Web hosts.
+    * SMBv1/CIFS is insecure, deprecated and kinda tricky to be implemented due to strict memory allignment in Swift.
 
 ## Requirements
 
-- **Swift 3.0 +**
+- **Swift 3.0 or higher**
 - iOS 8.0 , OSX 10.10
 - XCode 8.0
 
-Legacy version is available in swift-2 branch
+Legacy version is available in swift-2 branch.
 
 ## Installation
 
+### Important: this library has been renamed to avoid conflict in iOS 11, macOS 10.13 and Xcode 9.0. Please read issue [#53](https://github.com/amosavian/FileProvider/issues/53) to find more.
+
+
 ### Cocoapods / Carthage / Swift Package Manager
 
 Add this line to your pods file:
 
 ```ruby
-pod "FileProvider"
+pod "FilesProvider"
 ```
 
 Or add this to Cartfile:
@@ -67,7 +77,7 @@ github "amosavian/FileProvider"
 Or to use in Swift Package Manager add this line in `Dependencies`:
 
 ```swift
-.Package(url: "https://github.com/amosavian/FileProvider.git", majorVersion: 0, minorVersion: 12)
+.Package(url: "https://github.com/amosavian/FileProvider.git", majorVersion: 0)
 ```
 
 ### Manually
@@ -93,7 +103,7 @@ Then you can do either:
 
 * Copy Source folder to your project and Voila!
 
-* Drop `FileProvider.xcodeproj` to you Xcode workspace and add the framework to your Embeded Binaries in target.
+* Drop `FilesProvider.xcodeproj` to you Xcode workspace and add the framework to your Embeded Binaries in target.
 
 ## Usage
 
@@ -104,6 +114,8 @@ Each provider has a specific class which conforms to FileProvider protocol and s
 For LocalFileProvider if you want to deal with `Documents` folder
 
 ```	swift
+import FilesProvider
+
 let documentsProvider = LocalFileProvider()
 
 // Equals with:
@@ -117,6 +129,8 @@ let documentsProvider = LocalFileProvider(baseURL: documentsURL)
 Also for using group shared container:
 
 ```swift
+import FilesProvider
+
 let documentsProvider = LocalFileProvider(sharedContainerId: "group.yourcompany.appContainer")
 // Replace your group identifier
 ```
@@ -126,6 +140,8 @@ You can't change the base url later. and all paths are related to this base url
 To initialize an iCloud Container provider look at [here](https://medium.com/ios-os-x-development/icloud-drive-documents-1a46b5706fe1) to see how to update project settings then use below code, This will automatically manager creating Documents folder in container:
 
 ```swift
+import FilesProvider
+
 let documentsProvider = CloudFileProvider(containerId: nil)
 ```
 
@@ -133,6 +149,8 @@ let documentsProvider = CloudFileProvider(containerId: nil)
 For remote file providers authentication may be necessary:
 
 ```	swift
+import FilesProvider
+
 let credential = URLCredential(user: "user", password: "pass", persistence: .permanent)
 let webdavProvider = WebDAVFileProvider(baseURL: URL(string: "http://www.example.com/dav")!, credential: credential)
 ```
@@ -228,10 +246,10 @@ To get list of files in a directory:
 documentsProvider.contentsOfDirectory(path: "/", completionHandler: {
 	contents, error in
 	for file in contents {
-		print("Name: \(attributes.name)")
-		print("Size: \(attributes.size)")
-		print("Creation Date: \(attributes.creationDate)")
-		print("Modification Date: \(attributes.modifiedDate)")
+		print("Name: \(file.name)")
+		print("Size: \(file.size)")
+		print("Creation Date: \(file.creationDate)")
+		print("Modification Date: \(file.modifiedDate)")
 	}
 })
 ```
@@ -248,15 +266,6 @@ func storageProperties(completionHandler: { total, used in
 	
 * if this function is unavailable on provider or an error has been occurred, total space will be reported `-1` and used space `0`
 
-### Change current directory
-
-```swift
-documentsProvider.currentPath = "/New Folder"
-// now path is ~/Documents/New Folder
-```
-	
-You can then pass "" (empty string) to `contentsOfDirectory` method to list files in current directory.
-
 ### Creating File and Folders
 
 Creating new directory:
@@ -271,12 +280,7 @@ documentsProvider.create(folder: "new folder", at: "/", completionHandler: { err
 })
 ```
 
-Creating new file from data:
-
-```swift
-let data = "hello world!".data(encoding: .utf8)
-documentsProvider.create(file: "newFile.txt", at: "/", contents: data, completionHandler: nil)
-```
+To create a file, use `writeContents(path:, content:, atomically:, completionHandler:)` method.
 
 ### Copy and Move/Rename Files
 
@@ -300,8 +304,6 @@ documentsProvider.moveItem(path: "new folder/old.txt", to: "new.txt", overwrite:
 documentsProvider.removeItem(path: "new.txt", completionHandler: nil)
 ```
 
-***Caution:*** This method will delete directories with all it's contents recursively.
-
 ### Fetching Contents of File
 
 There is two method for this purpose, one of them loads entire file into `Data` and another can load a portion of file.
@@ -333,6 +335,33 @@ let data = "What's up Newyork!".data(encoding: .utf8)
 documentsProvider.writeContents(path: "old.txt", content: data, atomically: true, completionHandler: nil)
 ```
 
+### Copying Files to and From Local Storage
+
+There are two methods to download and upload files between provider's and local storage. These methods use `URLSessionDownloadTask` and `URLSessionUploadTask` classes and allows to use background session and provide progress via delegate.
+
+To upload a file:
+
+```swift
+let fileURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!.appendingPathComponent("image.jpg")
+documentsProvider.copyItem(localFile: fileURL, to: "/upload/image.jpg", overwrite: true, completionHandler: nil)
+```
+
+To download a file:
+
+```swift
+let fileURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!.appendingPathComponent("image.jpg")
+documentsProvider.copyItem(path: "/download/image.jpg", toLocalURL: fileURL, overwrite: true, completionHandler: nil)
+```
+
+* It's safe only to assume these methods **won't** handle directories to upload/download recursively. If you need, you can list directories, create directories on target and copy files using these methods.
+* FTP provider allows developer to either use apple implemented `URLSessionDownloadTask` or custom implemented method based on stream task via `useAppleImplementation` property. FTP protocol is not supported by background session.
+
+### Operation Progress
+
+Creating/Copying/Deleting/Searching functions return a `(NS)Progress`. It provides operation type, progress and a `.cancel()` method which allows you to cancel operation in midst. You can check `cancellable` property to check either you can cancel operation via this object or not.
+
+- **Note:** Progress reporting is not supported by native `(NS)FileManager` so `LocalFileProvider`.
+
 ### Undo Operations
 
 Providers conform to `FileProviderUndoable` can perform undo for **some** operations like moving/renaming, copying and creating (file or folder). **Now, only `LocalFileProvider` supports this feature.** To implement:
@@ -376,12 +405,6 @@ class ViewController: UIViewController
 }
 ```
 
-### Operation Handle
-
-Creating/Copying/Deleting functions return a `OperationHandle` for remote operations. It provides operation type, progress and a `.cancel()` method which allows you to cancel operation in midst.
-
-It's not supported by native `(NS)FileManager` so `LocalFileProvider`, but this functionality will be added to future `PosixFileProvider` class.
-
 ### File Coordination
 
 `LocalFileProvider` and its descendents has a `isCoordinating` property. By setting this, provider will use `NSFileCoordinating` class to do all file operations. It's mandatory for iCloud, while recommended when using shared container or anywhere that simultaneous operations on a file/folder is common.
@@ -413,9 +436,10 @@ To check either file thumbnail is supported or not and fetch thumbnail, use (and
 
 ```swift
 let path = "/newImage.jpg"
-let thumbSize = CGSize(width: 64, height: 64)
+let thumbSize = CGSize(width: 64, height: 64) // or nil which renders to default dimension of provider
 if documentsProvider.thumbnailOfFileSupported(path: path {
     documentsProvider.thumbnailOfFile(path: file.path, dimension: thumbSize, completionHandler: { (image, error) in
+        // Interacting with UI must be placed in main thread
         DispatchQueue.main.async {
             self.previewImage.image = image
         }
@@ -443,9 +467,10 @@ if documentsProvider..propertiesOfFile(path: file.path, completionHandler: { (pr
 
 We would love for you to contribute to **FileProvider**, check the `LICENSE` file for more info.
 
-Things to do:
+Things you may consider to help us:
 
-- [ ] Implement Test-case (XCTest)
+- [ ] Implement request/response stack for `SMBClient`
+- [ ] Implement Test-case (`XCTest`)
 - [ ] Add Sample project for iOS
 - [ ] Add Sample project for macOS
 
@@ -466,10 +491,11 @@ Distributed under the MIT license. See `LICENSE` for more information.
 
 [https://github.com/amosavian/](https://github.com/amosavian/)
 
-[cocoapods]: https://cocoapods.org/pods/FileProvider
-[swift-image]: https://img.shields.io/badge/swift-3.0-orange.svg
+[cocoapods]: https://cocoapods.org/pods/FilesProvider
+[cocoapods-old]: https://cocoapods.org/pods/FileProvider
+[swift-image]: https://img.shields.io/badge/swift-3.0,%203.1-orange.svg
 [swift-url]: https://swift.org/
-[platform-image]: https://img.shields.io/cocoapods/p/FileProvider.svg
+[platform-image]: https://img.shields.io/cocoapods/p/FilesProvider.svg
 [license-image]: https://img.shields.io/github/license/amosavian/FileProvider.svg
 [license-url]: LICENSE
 [codebeat-image]: https://codebeat.co/badges/7b359f48-78eb-4647-ab22-56262a827517
@@ -479,7 +505,9 @@ Distributed under the MIT license. See `LICENSE` for more information.
 [release-url]: https://github.com/amosavian/FileProvider/releases
 [release-image]: https://img.shields.io/github/release/amosavian/FileProvider.svg
 [carthage-image]: https://img.shields.io/badge/Carthage-compatible-4BC51D.svg
-[cocoapods-downloads]: https://img.shields.io/cocoapods/dt/FileProvider.svg
-[cocoapods-apps]: https://img.shields.io/cocoapods/at/FileProvider.svg
-[docs-image]: https://img.shields.io/cocoapods/metrics/doc-percent/FileProvider.svg
-[docs-url]: http://cocoadocs.org/docsets/FileProvider/
+[cocoapods-downloads-old]: https://img.shields.io/cocoapods/dt/FileProvider.svg
+[cocoapods-apps-old]: https://img.shields.io/cocoapods/at/FileProvider.svg
+[cocoapods-downloads]: https://img.shields.io/cocoapods/dt/FilesProvider.svg
+[cocoapods-apps]: https://img.shields.io/cocoapods/at/FilesProvider.svg
+[docs-image]: https://img.shields.io/cocoapods/metrics/doc-percent/FilesProvider.svg
+[docs-url]: http://cocoadocs.org/docsets/FilesProvider/

Sources/AEXML/LICENSE

@@ -0,0 +1,19 @@
+Copyright (c) 2014-2017 Marko Tadić <tadija@me.com> http://tadija.net
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Sources/CloudFileProvider.swift

@@ -15,7 +15,7 @@ import Foundation
  To setup a functional iCloud container, please
  [read this page](https://medium.com/ios-os-x-development/icloud-drive-documents-1a46b5706fe1).
  */
-open class CloudFileProvider: LocalFileProvider {
+open class CloudFileProvider: LocalFileProvider, FileProviderSharing {
     /// An string to identify type of provider.
     open override class var type: String { return "iCloudDrive" }
     
@@ -71,9 +71,14 @@ open class CloudFileProvider: LocalFileProvider {
         super.init(baseURL: baseURL)
         self.isCoorinating = true
         
-        dispatch_queue = DispatchQueue(label: "FileProvider.\(type(of: self).type)", attributes: .concurrent)
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
         operation_queue = OperationQueue()
-        operation_queue.name = "FileProvider.\(type(of: self).type).Operation"
+        operation_queue.name = "\(queueLabel).Operation"
         
         fileManager.url(forUbiquityContainerIdentifier: containerId)
         opFileManager.url(forUbiquityContainerIdentifier: containerId)
@@ -128,7 +133,7 @@ open class CloudFileProvider: LocalFileProvider {
             query.valueListAttributes = [NSMetadataItemURLKey, NSMetadataItemFSNameKey, NSMetadataItemPathKey, NSMetadataItemFSSizeKey, NSMetadataItemContentTypeTreeKey, NSMetadataItemFSCreationDateKey, NSMetadataItemFSContentChangeDateKey]
             query.searchScopes = [self.scope.rawValue]
             var finishObserver: NSObjectProtocol?
-            finishObserver = NotificationCenter.default.addObserver(forName: NSNotification.Name.NSMetadataQueryDidFinishGathering, object: query, queue: nil, using: { (notification) in
+            finishObserver = NotificationCenter.default.addObserver(forName: .NSMetadataQueryDidFinishGathering, object: query, queue: nil, using: { (notification) in
                 defer {
                     query.stop()
                     NotificationCenter.default.removeObserver(finishObserver!)
@@ -195,7 +200,7 @@ open class CloudFileProvider: LocalFileProvider {
             query.valueListAttributes = [NSMetadataItemURLKey, NSMetadataItemFSNameKey, NSMetadataItemPathKey, NSMetadataItemFSSizeKey, NSMetadataItemContentTypeTreeKey, NSMetadataItemFSCreationDateKey, NSMetadataItemFSContentChangeDateKey]
             query.searchScopes = [self.scope.rawValue]
             var finishObserver: NSObjectProtocol?
-            finishObserver = NotificationCenter.default.addObserver(forName: NSNotification.Name.NSMetadataQueryDidFinishGathering, object: query, queue: nil, using: { (notification) in
+            finishObserver = NotificationCenter.default.addObserver(forName: .NSMetadataQueryDidFinishGathering, object: query, queue: nil, using: { (notification) in
                 defer {
                     query.stop()
                     NotificationCenter.default.removeObserver(finishObserver!)
@@ -238,13 +243,13 @@ open class CloudFileProvider: LocalFileProvider {
      - Note: For now only it's limited to file names. `query` parameter may take `NSPredicate` format in near future.
      
      - Parameters:
-     - path: location of directory to start search
-     - recursive: Searching subdirectories of path
-     - query: Simple string of file name to be search (for now).
-     - foundItemHandler: Closure which is called when a file is found
-     - completionHandler: Closure which will be called after finishing search. Returns an arry of `FileObject` or error if occured.
+         - path: location of directory to start search
+         - recursive: Searching subdirectories of path
+         - query: Simple string of file name to be search (for now).
+         - foundItemHandler: Closure which is called when a file is found
+         - completionHandler: Closure which will be called after finishing search. Returns an arry of `FileObject` or error if occured.
      */
-    open override func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) {
+    open override func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
         
         let mapDict: [String: String] = ["url": NSMetadataItemURLKey, "name": NSMetadataItemFSNameKey, "path": NSMetadataItemPathKey, "filesize": NSMetadataItemFSSizeKey, "modifiedDate": NSMetadataItemFSContentChangeDateKey, "creationDate": NSMetadataItemFSCreationDateKey, "contentType": NSMetadataItemContentTypeKey]
         
@@ -277,6 +282,8 @@ open class CloudFileProvider: LocalFileProvider {
             }
         }
         
+        let progress = Progress(parent: nil, userInfo: nil)
+        
         dispatch_queue.async {
             let pathURL = self.url(of: path)
             let mdquery = NSMetadataQuery()
@@ -285,6 +292,10 @@ open class CloudFileProvider: LocalFileProvider {
             
             var lastReportedCount = 0
             
+            progress.cancellationHandler = { [weak mdquery] in
+                mdquery?.stop()
+            }
+            
             if let foundItemHandler = foundItemHandler {
                 var updateObserver: NSObjectProtocol?
                 
@@ -309,6 +320,7 @@ open class CloudFileProvider: LocalFileProvider {
                         }
                     }
                     lastReportedCount = mdquery.resultCount
+                    progress.totalUnitCount = Int64(lastReportedCount)
                     
                     mdquery.enableUpdates()
                 })
@@ -341,12 +353,14 @@ open class CloudFileProvider: LocalFileProvider {
                         contents.append(file)
                     }
                 }
+                progress.completedUnitCount = Int64(contents.count)
                 self.dispatch_queue.async {
                     completionHandler(contents, nil)
                 }
             })
             
             DispatchQueue.main.async {
+                progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
                 if !mdquery.start() {
                     self.dispatch_queue.async {
                         completionHandler([], self.throwError(path, code: CocoaError.fileReadNoPermission))
@@ -354,6 +368,8 @@ open class CloudFileProvider: LocalFileProvider {
                 }
             }
         }
+        
+        return progress
     }
     
     open override func isReachable(completionHandler: @escaping (Bool) -> Void) {
@@ -370,29 +386,11 @@ open class CloudFileProvider: LocalFileProvider {
        - folder: Directory name.
        - at: Parent path of new directory.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
+     - Returns: A `Progress` object to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
      */
     @discardableResult
-    open override func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        guard let r = super.create(folder: folderName, at: atPath, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
-    }
-    
-    /**
-     Creates an new file with data passed to method asynchronously.
-     Returns error via completionHandler if file is already exists.
-     
-     - Parameters:
-       - file: New file name with extension separated by period.
-       - at: Parent path of new file.
-       - data: Data of new files. Pass nil or `Data()` to create empty file.
-       - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
-     */
-    @discardableResult
-    open override func create(file fileName: String, at atPath: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        guard let r = super.create(file: fileName, at: atPath, contents: data, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return super.create(folder: folderName, at: atPath, completionHandler: completionHandler)
     }
     
     /**
@@ -405,12 +403,11 @@ open class CloudFileProvider: LocalFileProvider {
        - to: destination path of file or directory, including file/directory name.
        - overwrite: Destination file should be overwritten if file is already exists. **Default** is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
+     - Returns: A `Progress` object to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
      */
     @discardableResult
-    open override func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        guard let r = super.moveItem(path: path, to: toPath, overwrite: overwrite, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return super.moveItem(path: path, to: toPath, overwrite: overwrite, completionHandler: completionHandler)
     }
     
     /**
@@ -423,12 +420,11 @@ open class CloudFileProvider: LocalFileProvider {
        - to: destination path of file or directory, including file/directory name.
        - overwrite: Destination file should be overwritten if file is already exists. **Default** is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
+     - Returns: A `Progress` object to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
      */
     @discardableResult
-    open override func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        guard let r = super.copyItem(path: path, to: toPath, overwrite: overwrite, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return super.copyItem(path: path, to: toPath, overwrite: overwrite, completionHandler: completionHandler)
     }
     
     /**
@@ -441,13 +437,11 @@ open class CloudFileProvider: LocalFileProvider {
      - Parameters:
        - path: file or directory path.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
-     
+     - Returns: A `Progress` object to get progress or cancel progress. Doesn't work on `CloudFileProvider`.
      */
     @discardableResult
-    open override func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        guard let r = super.removeItem(path: path, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return super.removeItem(path: path, completionHandler: completionHandler)
     }
     
     /**
@@ -459,12 +453,18 @@ open class CloudFileProvider: LocalFileProvider {
        - to: destination path of file, including file/directory name.
        - overwrite: Destination file should be overwritten if file is already exists. **Default** is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress.
+     - Returns: A `Progress` object to get progress or cancel progress.
      */
     @discardableResult
-    open override func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open override func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         // TODO: Make use of overwrite parameter
         let opType = FileOperationType.copy(source: localFile.absoluteString, destination: toPath)
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.isCancellable = false
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        monitorFile(path: toPath, opType: opType, progress: progress)
         operation_queue.addOperation {
             let tempFolder: URL
             if #available(iOS 10.0, macOS 10.12, tvOS 10.0, *) {
@@ -492,7 +492,7 @@ open class CloudFileProvider: LocalFileProvider {
                 })
             }
         }
-        return CloudOperationHandle(operationType: opType, baseURL: self.baseURL)
+        return progress
     }
     
     /**
@@ -503,12 +503,17 @@ open class CloudFileProvider: LocalFileProvider {
        - path: original file or directory path.
        - toLocalURL: destination local url of file, including file/directory name.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress.
+     - Returns: A `Progress` object to get progress or cancel progress.
      */
     @discardableResult
-    open override func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open override func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.copy(source: path, destination: toLocalURL.absoluteString)
-        
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.isCancellable = false
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        monitorFile(path: path, opType: opType, progress: progress)
         do {
             try self.opFileManager.startDownloadingUbiquitousItem(at: self.url(of: path))
         } catch let e {
@@ -518,9 +523,8 @@ open class CloudFileProvider: LocalFileProvider {
             })
             return nil
         }
-        
-        guard let r = super.copyItem(path: path, toLocalURL: toLocalURL, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+        let _ = super.copyItem(path: path, toLocalURL: toLocalURL, completionHandler: completionHandler)
+        return progress
     }
     
     /**
@@ -532,12 +536,18 @@ open class CloudFileProvider: LocalFileProvider {
        - completionHandler: a closure with result of file contents or error.
          `contents`: contents of file in a `Data` object.
          `error`: Error returned by system.
-     - Returns: An `OperationHandle` to get progress or cancel progress.
+     - Returns: A `Progress` object to get progress or cancel progress.
      */
     @discardableResult
-    open override func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
-        guard let r = super.contents(path: path, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
+        let operation = FileOperationType.fetch(path: path)
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        monitorFile(path: path, opType: operation, progress: progress)
+        _ = super.contents(path: path, completionHandler: completionHandler)
+        return progress
     }
     
     /**
@@ -551,12 +561,18 @@ open class CloudFileProvider: LocalFileProvider {
        - completionHandler: a closure with result of file contents or error.
          `contents`: contents of file in a `Data` object.
          `error`: Error returned by system.
-     - Returns: An `OperationHandle` to get progress or cancel progress.
+     - Returns: A `Progress` object to get progress or cancel progress.
      */
     @discardableResult
-    open override func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
-        guard let r = super.contents(path: path, offset: offset, length: length, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
+        let operation = FileOperationType.fetch(path: path)
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        monitorFile(path: path, opType: operation, progress: progress)
+        _ = super.contents(path: path, offset: offset, length: length, completionHandler: completionHandler)
+        return progress
     }
     
     /**
@@ -568,12 +584,18 @@ open class CloudFileProvider: LocalFileProvider {
        - overwrite: Destination file should be overwritten if file is already exists. Default is `false`.
        - atomically: data will be written to a temporary file before writing to final location. Default is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: A `Progress` object to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    open override func writeContents(path: String, contents data: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        guard let r = super.writeContents(path: path, contents: data, atomically: atomically, overwrite: overwrite, completionHandler: completionHandler) else { return nil }
-        return CloudOperationHandle(operationType: r.operationType, baseURL: self.baseURL)
+    open override func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let operation = FileOperationType.fetch(path: path)
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        monitorFile(path: path, opType: operation, progress: progress)
+        _ = super.writeContents(path: path, contents: data, atomically: atomically, overwrite: overwrite, completionHandler: completionHandler)
+        return progress
     }
     
     fileprivate var monitors = [String: (NSMetadataQuery, NSObjectProtocol)]()
@@ -645,7 +667,7 @@ open class CloudFileProvider: LocalFileProvider {
         
         let path = self.relativePathOf(url: url)
         let rpath = path.hasPrefix("/") ? path.substring(from: path.index(after: path.startIndex)) : path
-        let relativeUrl = URL(string: rpath, relativeTo: self.baseURL)
+        let relativeUrl = URL(string: rpath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? rpath, relativeTo: self.baseURL)
         let file = FileObject(url: relativeUrl ?? url, name: name, path: path)
         
         file.size = (attribs[NSMetadataItemFSSizeKey] as? NSNumber)?.int64Value ?? -1
@@ -658,6 +680,57 @@ open class CloudFileProvider: LocalFileProvider {
         return file
     }
     
+    func monitorFile(path: String, opType: FileOperationType, progress: Progress?) {
+        dispatch_queue.async {
+            let pathURL = self.url(of: path)
+            let size = pathURL.fileSize
+            progress?.totalUnitCount = size > 0 ? size : 0
+            let query = NSMetadataQuery()
+            query.predicate = NSPredicate(format: "%K LIKE %@", NSMetadataItemPathKey, pathURL.path)
+            query.valueListAttributes = [NSMetadataItemURLKey, NSMetadataItemFSNameKey, NSMetadataItemPathKey, NSMetadataUbiquitousItemPercentDownloadedKey, NSMetadataUbiquitousItemPercentUploadedKey, NSMetadataItemFSSizeKey]
+            query.searchScopes = [self.scope.rawValue]
+            var updateObserver: NSObjectProtocol?
+            updateObserver = NotificationCenter.default.addObserver(forName: .NSMetadataQueryDidUpdate, object: query, queue: nil, using: { (notification) in
+                query.disableUpdates()
+                
+                guard let item = (query.results as? [NSMetadataItem])?.first else {
+                    return
+                }
+                
+                if progress?.totalUnitCount == 0, let size = item.value(forAttribute: NSMetadataItemFSSizeKey) as? Int64 {
+                    progress?.totalUnitCount = size
+                }
+                let downloaded = item.value(forAttribute: NSMetadataUbiquitousItemPercentDownloadedKey) as? Double ?? 0
+                let uploaded = item.value(forAttribute: NSMetadataUbiquitousItemPercentUploadedKey) as? Double ?? 0
+                if (downloaded == 0 || downloaded == 100) && (uploaded > 0 && uploaded < 100) {
+                    progress?.completedUnitCount = Int64(uploaded / 100 * Double(progress?.totalUnitCount ?? 0))
+                    DispatchQueue.main.async {
+                        self.delegate?.fileproviderProgress(self, operation: opType, progress: Float(uploaded / 100))
+                    }
+                } else if (uploaded == 0 || uploaded == 100) && (downloaded > 0 && downloaded < 100) {
+                    progress?.completedUnitCount = Int64(downloaded / 100 * Double(progress?.totalUnitCount ?? 0))
+                    DispatchQueue.main.async {
+                        self.delegate?.fileproviderProgress(self, operation: opType, progress: Float(downloaded / 100))
+                    }
+                } else if uploaded == 100 || downloaded == 100 {
+                    progress?.completedUnitCount = progress?.totalUnitCount ?? 0
+                    query.stop()
+                    NotificationCenter.default.removeObserver(updateObserver!)
+                    DispatchQueue.main.async {
+                        self.delegate?.fileproviderSucceed(self, operation: opType)
+                    }
+                }
+                
+                query.enableUpdates()
+            })
+            
+            DispatchQueue.main.async {
+                progress?.setUserInfoObject(Date(), forKey: .startingTimeKey)
+                query.start()
+            }
+        }
+    }
+    
     /// Removes local copy of file, but spares cloud copy/
     /// - Parameter path: Path of file or directory to be remoed from local
     /// - Parameter completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
@@ -672,19 +745,6 @@ open class CloudFileProvider: LocalFileProvider {
         }
     }
     
-    /**
-     Genrates a public url to a file to be shared with other users and can be downloaded without authentication.
-     
-     - Important: URL will be available for a limitied time, determined in `expiration` argument.
-     
-     - Parameters:
-     - to: path of file, including file/directory name.
-     - completionHandler: a closure with result of directory entries or error.
-     `link`: a url returned by Dropbox to share.
-     `attribute`: a `FileObject` containing the attributes of the item.
-     `expiration`: a `Date` object, determines when the public url will expires.
-     `error`: Error returned by Dropbox.
-     */
     open func publicLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: FileObject?, _ expiration: Date?, _ error: Error?) -> Void)) {
         operation_queue.addOperation {
             do {
@@ -702,6 +762,7 @@ open class CloudFileProvider: LocalFileProvider {
     }
 }
 
+/// Scope of iCloud, wrapper for NSMetadataQueryUbiquitous...Scope constants
 public enum UbiquitousScope: RawRepresentable {
     /// Search all files not in the Documents directories of the app’s iCloud container directories.
     /// Use this scope to store user-related data files that your app needs to share 
@@ -734,89 +795,36 @@ public enum UbiquitousScope: RawRepresentable {
     }
 }
 
-open class CloudOperationHandle: OperationHandle {
-    public let baseURL: URL?
-    public let operationType: FileOperationType
+/*
+func getMetadataItem(url: URL) -> NSMetadataItem? {
+    let query = NSMetadataQuery()
+    query.predicate = NSPredicate(format: "(%K LIKE %@)", NSMetadataItemPathKey, url.path)
+    query.searchScopes = [NSMetadataQueryUbiquitousDocumentsScope, NSMetadataQueryUbiquitousDataScope]
     
-    init (operationType: FileOperationType, baseURL: URL?) {
-        self.baseURL = baseURL
-        self.operationType = operationType
-    }
+    var item: NSMetadataItem?
     
-    private var sourceURL: URL? {
-        guard let source = operationType.source, let baseURL = baseURL else { return nil }
-        return source.hasPrefix("file://") ? URL(fileURLWithPath: source) : baseURL.appendingPathComponent(source)
-    }
-    
-    private var destURL: URL? {
-        guard let dest = operationType.destination, let baseURL = baseURL else { return nil }
-        return dest.hasPrefix("file://") ? URL(fileURLWithPath: dest) : baseURL.appendingPathComponent(dest)
-    }
-    
-    open var bytesSoFar: Int64 {
-        assert(!Thread.isMainThread, "Don't run \(#function) method on main thread")
-        
-        guard let url = destURL ?? sourceURL, let item = CloudOperationHandle.getMetadataItem(url: url) else { return 0 }
-        let downloaded = item.value(forAttribute: NSMetadataUbiquitousItemPercentDownloadedKey) as? Double ?? 0
-        let uploaded = item.value(forAttribute: NSMetadataUbiquitousItemPercentUploadedKey) as? Double ?? 0
-        guard let size = item.value(forAttribute: NSMetadataItemFSSizeKey) as? Int64 else { return -1 }
-        if (downloaded == 0 || downloaded == 100) && (uploaded > 0 && uploaded < 100) {
-            return Int64(uploaded * (Double(size) / 100))
-        } else if (uploaded == 0 || uploaded == 100) && (downloaded > 0 && downloaded < 100) {
-            return Int64(downloaded * (Double(size) / 100))
-        } else if uploaded == 100 || downloaded == 100 {
-            return size
+    let group = DispatchGroup()
+    group.enter()
+    var finishObserver: NSObjectProtocol?
+    finishObserver = NotificationCenter.default.addObserver(forName: .NSMetadataQueryDidFinishGathering, object: query, queue: nil, using: { (notification) in
+        defer {
+            query.stop()
+            group.leave()
+            NotificationCenter.default.removeObserver(finishObserver!)
         }
-        return 0
-    }
-    
-    open var totalBytes: Int64 {
-        assert(!Thread.isMainThread, "Don't run \(#function) method on main thread")
-        guard let url = destURL ?? sourceURL, let item = CloudOperationHandle.getMetadataItem(url: url) else { return -1 }
-        return item.value(forAttribute: NSMetadataItemFSSizeKey) as? Int64 ?? -1
-    }
-    
-    open var inProgress: Bool {
-        guard let url = destURL ?? sourceURL, let item = CloudOperationHandle.getMetadataItem(url: url) else { return false }
-        let downloadStatus = item.value(forAttribute: NSMetadataUbiquitousItemDownloadingStatusKey) as? String ?? NSMetadataUbiquitousItemDownloadingStatusNotDownloaded
-        let isUploading = item.value(forAttribute: NSMetadataUbiquitousItemIsUploadingKey) as? Bool ?? false
-        return downloadStatus == NSMetadataUbiquitousItemDownloadingStatusCurrent || isUploading
-    }
-    
-    /// Not usable in local provider
-    open func cancel() -> Bool {
-        return false
-    }
-    
-    fileprivate static func getMetadataItem(url: URL) -> NSMetadataItem? {
-        let query = NSMetadataQuery()
-        query.predicate = NSPredicate(format: "(%K LIKE %@)", NSMetadataItemPathKey, url.path)
-        query.searchScopes = [NSMetadataQueryUbiquitousDocumentsScope, NSMetadataQueryUbiquitousDataScope]
         
-        var item: NSMetadataItem?
-        
-        let group = DispatchGroup()
-        group.enter()
-        var finishObserver: NSObjectProtocol?
-        finishObserver = NotificationCenter.default.addObserver(forName: .NSMetadataQueryDidFinishGathering, object: query, queue: nil, using: { (notification) in
-            defer {
-                query.stop()
-                group.leave()
-                NotificationCenter.default.removeObserver(finishObserver!)
-            }
-            
-            if query.resultCount > 0 {
-                item = query.result(at: 0) as? NSMetadataItem
-            }
-            
-            query.disableUpdates()
-            
-        })
-        
-        DispatchQueue.main.async {
-            query.start()
+        if query.resultCount > 0 {
+            item = query.result(at: 0) as? NSMetadataItem
         }
-        _ = group.wait(timeout: .now() + 30)
-        return item
+        
+        query.disableUpdates()
+        
+    })
+    
+    DispatchQueue.main.async {
+        query.start()
     }
+    _ = group.wait(timeout: .now() + 30)
+    return item
 }
+*/

Sources/DropboxFileProvider.swift

@@ -17,7 +17,7 @@ import CoreGraphics
  - Note: Uploading files and data are limited to 150MB, for now.
  */
 open class DropboxFileProvider: FileProviderBasicRemote {
-    open class var type: String { return "DropBox" }
+    open class var type: String { return "Dropbox" }
     open let baseURL: URL?
     open var currentPath: String
     
@@ -34,22 +34,40 @@ open class DropboxFileProvider: FileProviderBasicRemote {
     }
     
     open weak var delegate: FileProviderDelegate?
-    open let credential: URLCredential?
+    open var credential: URLCredential? {
+        didSet {
+            sessionDelegate?.credential = self.credential
+        }
+    }
     open private(set) var cache: URLCache?
     public var useCache: Bool
     public var validatingCache: Bool
    
     fileprivate var _session: URLSession?
-    fileprivate var sessionDelegate: SessionDelegate?
+    internal fileprivate(set) var sessionDelegate: SessionDelegate?
     public var session: URLSession {
-        if _session == nil {
-            self.sessionDelegate = SessionDelegate(fileProvider: self, credential: credential)
-            let config = URLSessionConfiguration.default
-            config.urlCache = cache
-            config.requestCachePolicy = .returnCacheDataElseLoad
-            _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDelegate?, delegateQueue: self.operation_queue)
+        get {
+            if _session == nil {
+                self.sessionDelegate = SessionDelegate(fileProvider: self)
+                let config = URLSessionConfiguration.default
+                config.urlCache = cache
+                config.requestCachePolicy = .returnCacheDataElseLoad
+                _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDelegate?, delegateQueue: self.operation_queue)
+                _session!.sessionDescription = UUID().uuidString
+                initEmptySessionHandler(_session!.sessionDescription!)
+            }
+            return _session!
+        }
+        
+        set {
+            assert(newValue.delegate is SessionDelegate, "session instances should have a SessionDelegate instance as delegate.")
+            _session = newValue
+            if session.sessionDescription?.isEmpty ?? true {
+                _session?.sessionDescription = UUID().uuidString
+            }
+            self.sessionDelegate = newValue.delegate as? SessionDelegate
+            initEmptySessionHandler(_session!.sessionDescription!)
         }
-        return _session!
     }
     
     fileprivate var _longpollSession: URLSession?
@@ -83,9 +101,14 @@ open class DropboxFileProvider: FileProviderBasicRemote {
         self.apiURL = URL(string: "https://api.dropboxapi.com/2/")!
         self.contentURL = URL(string: "https://content.dropboxapi.com/2/")!
         
-        dispatch_queue = DispatchQueue(label: "FileProvider.\(type(of: self).type)", attributes: .concurrent)
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
         operation_queue = OperationQueue()
-        operation_queue.name = "FileProvider.\(type(of: self).type).Operation"
+        operation_queue.name = "\(queueLabel).Operation"
     }
     
     public required convenience init?(coder aDecoder: NSCoder) {
@@ -117,15 +140,21 @@ open class DropboxFileProvider: FileProviderBasicRemote {
     }
     
     deinit {
+        if let sessionuuid = _session?.sessionDescription {
+            removeSessionHandler(for: sessionuuid)
+        }
+        
         if fileProviderCancelTasksOnInvalidating {
             _session?.invalidateAndCancel()
         } else {
             _session?.finishTasksAndInvalidate()
         }
+        
     }
     
     open func contentsOfDirectory(path: String, completionHandler: @escaping ((_ contents: [FileObject], _ error: Error?) -> Void)) {
-        list(path) { (contents, cursor, error) in
+        let progress = Progress(parent: nil, userInfo: nil)
+        list(path, progress: progress) { (contents, cursor, error) in
             completionHandler(contents, error)
         }
     }
@@ -134,8 +163,8 @@ open class DropboxFileProvider: FileProviderBasicRemote {
         let url = URL(string: "files/get_metadata", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         let requestDictionary: [String: AnyObject] = ["path": correctPath(path)! as NSString]
         request.httpBody = Data(jsonDictionary: requestDictionary)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
@@ -157,7 +186,7 @@ open class DropboxFileProvider: FileProviderBasicRemote {
         let url = URL(string: "users/get_space_usage", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             var totalSize: Int64 = -1
             var usedSize: Int64 = 0
@@ -170,12 +199,13 @@ open class DropboxFileProvider: FileProviderBasicRemote {
         task.resume()
     }
     
-    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) {
+    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
+        let progress = Progress(parent: nil, userInfo: nil)
         var foundFiles = [DropboxFileObject]()
         if let queryStr = query.findValue(forKey: "name", operator: .beginsWith) as? String {
             // Dropbox only support searching for file names begin with query in non-enterprise accounts.
             // We will use it if there is a `name BEGINSWITH[c] "query"` in predicate, then filter to form final result.
-            search(path, query: queryStr, foundItem: { (file) in
+            search(path, query: queryStr, progress: progress, foundItem: { (file) in
                 if query.evaluate(with: file.mapPredicate()) {
                     foundFiles.append(file)
                     foundItemHandler?(file)
@@ -186,7 +216,7 @@ open class DropboxFileProvider: FileProviderBasicRemote {
         } else {
             // Dropbox doesn't support searching attributes natively. The workaround is to fallback to listing all files
             // and filter it locally. It may have a network burden in case there is many files in Dropbox, so please use it concisely.
-            list(path, recursive: true, progressHandler: { (files, _, error) in
+            list(path, recursive: true, progress: progress, progressHandler: { (files, _, error) in
                 for file in files where query.evaluate(with: file.mapPredicate()) {
                     foundItemHandler?(file)
                 }
@@ -195,6 +225,7 @@ open class DropboxFileProvider: FileProviderBasicRemote {
                 completionHandler(predicatedFiles, error)
             })
         }
+        return progress
     }
     
     open func isReachable(completionHandler: @escaping (Bool) -> Void) {
@@ -207,32 +238,33 @@ open class DropboxFileProvider: FileProviderBasicRemote {
 }
 
 extension DropboxFileProvider: FileProviderOperations {
-    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         let path = (atPath as NSString).appendingPathComponent(folderName) + "/"
         return doOperation(.create(path: path), completionHandler: completionHandler)
     }
     
-    open func create(file fileName: String, at path: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let filePath = (path as NSString).appendingPathComponent(fileName)
-        return self.writeContents(path: filePath, contents: data ?? Data(), completionHandler: completionHandler)
-    }
-    
-    open func moveItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func moveItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         return doOperation(.move(source: path, destination: toPath), completionHandler: completionHandler)
     }
     
-    open func copyItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         return doOperation(.copy(source: path, destination: toPath), completionHandler: completionHandler)
     }
     
-    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         return doOperation(.remove(path: path), completionHandler: completionHandler)
     }
     
-    fileprivate func doOperation(_ operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    fileprivate func doOperation(_ operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> Progress? {
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: operation) ?? true == true else {
             return nil
         }
+        
+        let progress = Progress(totalUnitCount: 1)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         let url: String
         guard let sourcePath = operation.source else { return nil }
         let destPath = operation.destination
@@ -250,8 +282,8 @@ extension DropboxFileProvider: FileProviderOperations {
         }
         var request = URLRequest(url: URL(string: url, relativeTo: apiURL)!)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         var requestDictionary = [String: AnyObject]()
         if let dest = correctPath(destPath) as NSString? {
             requestDictionary["from_path"] = correctPath(sourcePath) as NSString?
@@ -265,15 +297,32 @@ extension DropboxFileProvider: FileProviderOperations {
             if let response = response as? HTTPURLResponse, response.statusCode >= 300, let code = FileProviderHTTPErrorCode(rawValue: response.statusCode) {
                  serverError = FileProviderDropboxError(code: code, path: sourcePath, errorDescription: String(data: data ?? Data(), encoding: .utf8))
             }
+            if serverError == nil && error == nil {
+                progress.completedUnitCount = 1
+            } else {
+                progress.cancel()
+            }
             completionHandler?(serverError ?? error)
             self.delegateNotify(operation, error: serverError ?? error)
         })
         task.taskDescription = operation.json
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: operation, tasks: [task])
+        return progress
     }
     
-    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        // check file is not a folder
+        guard (try? localFile.resourceValues(forKeys: [.fileResourceTypeKey]))?.fileResourceType ?? .unknown == .regular else {
+            dispatch_queue.async {
+                completionHandler?(self.throwError(localFile.path, code: URLError.fileIsDirectory))
+            }
+            return nil
+        }
+        
         let opType = FileOperationType.copy(source: localFile.absoluteString, destination: toPath)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
@@ -281,41 +330,60 @@ extension DropboxFileProvider: FileProviderOperations {
         return upload_simple(toPath, localFile: localFile, overwrite: overwrite, operation: opType, completionHandler: completionHandler)
     }
     
-    open func copyItem(path: String, toLocalURL destURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, toLocalURL destURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.copy(source: path, destination: destURL.absoluteString)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
         let url = URL(string: "files/download", relativeTo: contentURL)!
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         var request = URLRequest(url: url)
-        request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        let requestDictionary: [String: AnyObject] = ["path": path as NSString]
-        let requestJson = String(jsonDictionary: requestDictionary) ?? ""
-        request.setValue(requestJson, forHTTPHeaderField: "Dropbox-API-Arg")
-        let task = session.downloadTask(with: request, completionHandler: { (cacheURL, response, error) in
-            guard let cacheURL = cacheURL, let httpResponse = response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
-                let code = FileProviderHTTPErrorCode(rawValue: (response as? HTTPURLResponse)?.statusCode ?? -1)
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(dropboxArgKey: ["path": path as NSString])
+        let task = session.downloadTask(with: request)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+            if error != nil {
+                progress.cancel()
+            }
+            completionHandler?(error)
+        }
+        downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { tempURL in
+            guard let httpResponse = task.response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
+                let code = FileProviderHTTPErrorCode(rawValue: (task.response as? HTTPURLResponse)?.statusCode ?? -1)
                 let errorData : Data? = nil //Data(contentsOf:cacheURL) // TODO: Figure out how to get error response data for the error description
                 let serverError : FileProviderDropboxError? = code != nil ? FileProviderDropboxError(code: code!, path: path, errorDescription: String(data: errorData ?? Data(), encoding: .utf8)) : nil
-                completionHandler?(serverError ?? error)
+                if serverError != nil {
+                    progress.cancel()
+                }
+                completionHandler?(serverError)
                 return
             }
             do {
-                try FileManager.default.moveItem(at: cacheURL, to: destURL)
+                try FileManager.default.moveItem(at: tempURL, to: destURL)
                 completionHandler?(nil)
             } catch let e {
                 completionHandler?(e)
             }
-        })
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
 }
 
 extension DropboxFileProvider: FileProviderReadWrite {
-    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         if length == 0 || offset < 0 {
             dispatch_queue.async {
                 completionHandler(Data(), nil)
@@ -325,36 +393,59 @@ extension DropboxFileProvider: FileProviderReadWrite {
         
         let opType = FileOperationType.fetch(path: path)
         let url = URL(string: "files/download", relativeTo: contentURL)!
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         var request = URLRequest(url: url)
-        request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        if length > 0 {
-            request.setValue("bytes=\(offset)-\(offset + length - 1)", forHTTPHeaderField: "Range")
-        } else if offset > 0 && length < 0 {
-            request.setValue("bytes=\(offset)-", forHTTPHeaderField: "Range")
-        }
-        let requestDictionary: [String: AnyObject] = ["path": correctPath(path)! as NSString]
-        request.setValue(String(jsonDictionary: requestDictionary), forHTTPHeaderField: "Dropbox-API-Arg")
-        let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
-            var serverError: FileProviderDropboxError?
-            if let httpResponse = response as? HTTPURLResponse , httpResponse.statusCode >= 300, let code = FileProviderHTTPErrorCode(rawValue: httpResponse.statusCode) {
-                serverError = FileProviderDropboxError(code: code, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8))
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(rangeWithOffset: offset, length: length)
+        request.set(dropboxArgKey: ["path": correctPath(path)! as NSString])
+        let task = session.downloadTask(with: request)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+            if error != nil {
+                progress.cancel()
             }
-            let filedata = serverError ?? error == nil ? data : nil
-            completionHandler(filedata, serverError ?? error)
-        })
+            completionHandler(nil, error)
+        }
+        downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { tempURL in            
+            guard let httpResponse = task.response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
+                let code = FileProviderHTTPErrorCode(rawValue: (task.response as? HTTPURLResponse)?.statusCode ?? -1)
+                let errorData : Data? = nil //Data(contentsOf:cacheURL) // TODO: Figure out how to get error response data for the error description
+                let serverError : FileProviderDropboxError? = code != nil ? FileProviderDropboxError(code: code!, path: path, errorDescription: String(data: errorData ?? Data(), encoding: .utf8)) : nil
+                if serverError != nil {
+                    progress.cancel()
+                }
+                completionHandler(nil, serverError)
+                return
+            }
+            do {
+                let data = try Data(contentsOf: tempURL)
+                completionHandler(data, nil)
+            } catch let e {
+                completionHandler(nil, e)
+            }
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
     
-    public func writeContents(path: String, contents data: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.modify(path: path)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
         // FIXME: remove 150MB restriction
-        return upload_simple(path, data: data, overwrite: overwrite, operation: opType, completionHandler: completionHandler)
+        return upload_simple(path, data: data ?? Data(), overwrite: overwrite, operation: opType, completionHandler: completionHandler)
     }
     
     /*
@@ -374,42 +465,13 @@ extension DropboxFileProvider: FileProviderReadWrite {
     // TODO: Implement /get_account & /get_current_account
 }
 
-extension DropboxFileProvider {
-    /// *OBSOLETED:* Use `publicLink(to:, completionHandler: (URL?, DropboxFileObject?, Date?,  Error?))` function instead.
-    @available(*, obsoleted: 1.0, renamed: "publicLink(to:completionHandler:)", message: "Use publicLink(to:, completionHandler: (URL?, DropboxFileObject?, Date?,  Error?)) function instead.")
-    open func temporaryLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: DropboxFileObject?, _ error: Error?) -> Void)) {
-        self.publicLink(to: path) { (url, file, _, error) in
-            completionHandler(url, file, error)
-        }
-    }
-    
-    /// *OBSOLETED:* Use `publicLink(to:, completionHandler: (URL?, DropboxFileObject?, Date?,  Error?))` function instead.
-    @available(*, obsoleted: 1.0, renamed: "publicLink(to:completionHandler:)", message: "Use publicLink(to:, completionHandler: (URL?, DropboxFileObject?, Date?,  Error?)) function instead.")
-    open func temporaryLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: DropboxFileObject?, _ expiration: Date?, _ error: Error?) -> Void)) {
-        self.publicLink(to: path) { (url, file, expiration, error) in
-            completionHandler(url, file, expiration, error)
-        }
-    }
-    
-    /**
-     Genrates a public url to a file to be shared with other users and can be downloaded without authentication.
-     
-     - Important: URL will be available for a limitied time (4 hours according to Dropbox documentation).
-     
-     - Parameters:
-       - to: path of file, including file/directory name.
-       - completionHandler: a closure with result of directory entries or error.
-         `link`: a url returned by Dropbox to share.
-         `attribute`: a `FileObject` containing the attributes of the item.
-         `expiration`: a `Date` object, determines when the public url will expires.
-         `error`: Error returned by Dropbox.
-    */
-    open func publicLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: DropboxFileObject?, _ expiration: Date?, _ error: Error?) -> Void)) {
+extension DropboxFileProvider: FileProviderSharing {
+    open func publicLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: FileObject?, _ expiration: Date?, _ error: Error?) -> Void)) {
         let url = URL(string: "files/get_temporary_link", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         let requestDictionary: [String: AnyObject] = ["path": correctPath(path)! as NSString]
         request.httpBody = Data(jsonDictionary: requestDictionary)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
@@ -442,9 +504,9 @@ extension DropboxFileProvider {
        - remoteURL: a valid remote url to file.
        - to: Destination path of file, including file/directory name.
        - completionHandler: a closure with result of directory entries or error.
-         `jobId`: Job ID returned by Dropbox to monitor the copy/download progress.
-         `attribute`: A `FileObject` containing the attributes of the item.
-         `error`: Error returned by Dropbox.
+         - `jobId`: Job ID returned by Dropbox to monitor the copy/download progress.
+         - `attribute`: A `FileObject` containing the attributes of the item.
+         - `error`: Error returned by Dropbox.
      */
     open func copyItem(remoteURL: URL, to toPath: String, completionHandler: @escaping ((_ jobId: String?, _ attribute: DropboxFileObject?, _ error: Error?) -> Void)) {
         if remoteURL.isFileURL {
@@ -454,8 +516,8 @@ extension DropboxFileProvider {
         let url = URL(string: "files/save_url", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         let requestDictionary: [String: AnyObject] = ["path": correctPath(toPath)! as NSString, "url" : remoteURL.absoluteString as NSString]
         request.httpBody = Data(jsonDictionary: requestDictionary)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
@@ -489,8 +551,8 @@ extension DropboxFileProvider {
         let url = URL(string: "files/copy_reference/save", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         let requestDictionary: [String: AnyObject] = ["path": correctPath(toPath)! as NSString, "copy_reference" : reference as NSString]
         request.httpBody = Data(jsonDictionary: requestDictionary)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
@@ -538,26 +600,37 @@ extension DropboxFileProvider: ExtendedFileProvider {
     /// Default value for dimension is 64x64, according to Dropbox documentation
     open func thumbnailOfFile(path: String, dimension: CGSize?, completionHandler: @escaping ((_ image: ImageClass?, _ error: Error?) -> Void)) {
         let url: URL
+        let thumbAPI: Bool
         switch (path as NSString).pathExtension.lowercased() {
         case "jpg", "jpeg", "gif", "bmp", "png", "tif", "tiff":
             url = URL(string: "files/get_thumbnail", relativeTo: contentURL)!
+            thumbAPI = true
         case "doc", "docx", "docm", "xls", "xlsx", "xlsm":
             fallthrough
         case  "ppt", "pps", "ppsx", "ppsm", "pptx", "pptm":
             fallthrough
         case "rtf":
             url = URL(string: "files/get_preview", relativeTo: contentURL)!
+            thumbAPI = false
         default:
             return
         }
         var request = URLRequest(url: url)
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         var requestDictionary: [String: AnyObject] = ["path": path as NSString]
-        requestDictionary["format"] = "jpeg" as NSString
-        if let dimension = dimension {
-            requestDictionary["size"] = "w\(Int(dimension.width))h\(Int(dimension.height))" as NSString
+        if thumbAPI {
+            requestDictionary["format"] = "jpeg" as NSString
+            let size: String
+            switch dimension?.height ?? 64 {
+            case 0...32:    size = "w32h32"
+            case 33...64:   size = "w64h64"
+            case 65...128:  size = "w128h128"
+            case 129...480: size = "w640h480"
+            default: size = "w1024h768"
+            }
+            requestDictionary["size"] = size as NSString
         }
-        request.setValue(String(jsonDictionary: requestDictionary), forHTTPHeaderField: "Dropbox-API-Arg")
+        request.set(dropboxArgKey: requestDictionary)
         let task = self.session.dataTask(with: request, completionHandler: { (data, response, error) in
             var image: ImageClass? = nil
             if let r = response as? HTTPURLResponse, let result = r.allHeaderFields["Dropbox-API-Result"] as? String, let jsonResult = result.deserializeJSON() {
@@ -570,8 +643,12 @@ extension DropboxFileProvider: ExtendedFileProvider {
                     image = pageImage
                 } else if let contentType = (response as? HTTPURLResponse)?.allHeaderFields["Content-Type"] as? String, contentType.contains("text/html") {
                      // TODO: Implement converting html returned type of get_preview to image
-                } else {
-                    image = ImageClass(data: data)
+                } else if let fetchedimage = ImageClass(data: data){
+                    if let dimension = dimension {
+                        image = DropboxFileProvider.scaleDown(image: fetchedimage, toSize: dimension)
+                    } else {
+                        image = fetchedimage
+                    }
                 }
             }
             completionHandler(image, error)
@@ -583,8 +660,8 @@ extension DropboxFileProvider: ExtendedFileProvider {
         let url = URL(string: "files/get_metadata", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         let requestDictionary: [String: AnyObject] = ["path": correctPath(path)! as NSString, "include_media_info": NSNumber(value: true)]
         request.httpBody = Data(jsonDictionary: requestDictionary)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
@@ -594,7 +671,7 @@ extension DropboxFileProvider: ExtendedFileProvider {
             if let response = response as? HTTPURLResponse {
                 let code = FileProviderHTTPErrorCode(rawValue: response.statusCode)
                 serverError = code != nil ? FileProviderDropboxError(code: code!, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8)) : nil
-                if let json = data?.deserializeJSON(), let properties = json["media_info"] as? [String: Any] {
+                if let json = data?.deserializeJSON(), let properties = (json["media_info"] as? [String: Any])?["metadata"] as? [String: Any] {
                     (dic, keys) = self.mapMediaInfo(properties)
                 }
             }

Sources/DropboxHelper.swift

@@ -17,22 +17,18 @@ public struct FileProviderDropboxError: FileProviderHTTPError {
 
 /// Containts path, url and attributes of a Dropbox file or resource.
 public final class DropboxFileObject: FileObject {
-    internal init(name: String, path: String) {
-        super.init(url: URL(string: path) ?? URL(string: "/")!, name: name, path: path)
-    }
-    
     internal convenience init? (jsonStr: String) {
         guard let json = jsonStr.deserializeJSON() else { return nil }
         self.init(json: json)
     }
     
-    internal convenience init? (json: [String: AnyObject]) {
+    internal init? (json: [String: AnyObject]) {
         guard let name = json["name"] as? String else { return nil }
         guard let path = json["path_display"] as? String else { return nil }
-        self.init(name: name, path: path)
+        super.init(url: nil, name: name, path: path)
         self.size = (json["size"] as? NSNumber)?.int64Value ?? -1
-        self.serverTime = resolve(dateString: json["server_modified"] as? String ?? "")
-        self.modifiedDate = resolve(dateString: json["client_modified"] as? String ?? "")
+        self.serverTime = Date(rfcString: json["server_modified"] as? String ?? "")
+        self.modifiedDate = Date(rfcString: json["client_modified"] as? String ?? "")
         self.type = (json[".tag"] as? String) == "folder" ? .directory : .regular
         self.isReadOnly = (json["sharing_info"]?["read_only"] as? NSNumber)?.boolValue ?? false
         self.id = json["id"] as? String
@@ -42,10 +38,10 @@ public final class DropboxFileObject: FileObject {
     /// The time contents of file has been modified on server, returns nil if not set
     open internal(set) var serverTime: Date? {
         get {
-            return allValues[.serverDate] as? Date
+            return allValues[.serverDateKey] as? Date
         }
         set {
-            allValues[.serverDate] = newValue
+            allValues[.serverDateKey] = newValue
         }
     }
     
@@ -75,7 +71,11 @@ public final class DropboxFileObject: FileObject {
 
 // codebeat:disable[ARITY]
 internal extension DropboxFileProvider {
-    func list(_ path: String, cursor: String? = nil, prevContents: [DropboxFileObject] = [], recursive: Bool = false, session: URLSession? = nil, progressHandler: ((_ contents: [FileObject], _ nextCursor: String?, _ error: Error?) -> Void)? = nil, completionHandler: @escaping ((_ contents: [FileObject], _ cursor: String?, _ error: Error?) -> Void)) {
+    
+    
+    func list(_ path: String, cursor: String? = nil, prevContents: [DropboxFileObject] = [], recursive: Bool = false, session: URLSession? = nil, progress: Progress, progressHandler: ((_ contents: [FileObject], _ nextCursor: String?, _ error: Error?) -> Void)? = nil, completionHandler: @escaping ((_ contents: [FileObject], _ cursor: String?, _ error: Error?) -> Void)) {
+        if progress.isCancelled { return }
+        
         var requestDictionary = [String: AnyObject]()
         let url: URL
         if let cursor = cursor {
@@ -88,8 +88,8 @@ internal extension DropboxFileProvider {
         }
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         request.httpBody = Data(jsonDictionary: requestDictionary)
         let task = (session ?? self.session).dataTask(with: request, completionHandler: { (data, response, error) in
             var responseError: FileProviderDropboxError?
@@ -103,13 +103,14 @@ internal extension DropboxFileProvider {
                     for entry in entries {
                         if let entry = entry as? [String: AnyObject], let file = DropboxFileObject(json: entry) {
                             files.append(file)
+                            progress.totalUnitCount = Int64(files.count)
                         }
                     }
                     let ncursor = json["cursor"] as? String
                     let hasmore = (json["has_more"] as? NSNumber)?.boolValue ?? false
-                    if hasmore {
+                    if hasmore && !progress.isCancelled {
                         progressHandler?(files, ncursor, responseError ?? error)
-                        self.list(path, cursor: ncursor, prevContents: prevContents + files, completionHandler: completionHandler)
+                        self.list(path, cursor: ncursor, prevContents: prevContents + files, progress: progress, completionHandler: completionHandler)
                         return
                     }
                 }
@@ -117,80 +118,79 @@ internal extension DropboxFileProvider {
             progressHandler?(files, nil, responseError ?? error)
             completionHandler(prevContents + files, nil, responseError ?? error)
         })
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.taskDescription = FileOperationType.fetch(path: path).json
         task.resume()
     }
     
-    func upload_simple(_ targetPath: String, data: Data, modifiedDate: Date = Date(), overwrite: Bool, operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        if data.count > 150 * 1024 * 1024 {
-            let error = FileProviderDropboxError(code: .payloadTooLarge, path: targetPath, errorDescription: nil)
-            completionHandler?(error)
-            self.delegateNotify(.create(path: targetPath), error: error)
-            return nil
-        }
-        var requestDictionary = [String: AnyObject]()
-        let url: URL
-        url = URL(string: "files/upload", relativeTo: contentURL)!
-        requestDictionary["path"] = correctPath(targetPath) as NSString?
-        requestDictionary["mode"] = (overwrite ? "overwrite" : "add") as NSString
-        requestDictionary["client_modified"] = rfc3339utc(of: modifiedDate) as NSString
-        var request = URLRequest(url: url)
-        request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/octet-stream", forHTTPHeaderField: "Content-Type")
-        request.setValue(String(jsonDictionary: requestDictionary), forHTTPHeaderField: "Dropbox-API-Arg")
-        request.httpBody = data
-        let task = session.uploadTask(with: request, from: data, completionHandler: { (data, response, error) in
-            var responseError: FileProviderDropboxError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderDropboxError(code: rCode, path: targetPath, errorDescription: String(data: data ?? Data(), encoding: .utf8))
-            }
-            completionHandler?(responseError ?? error)
-            self.delegateNotify(.create(path: targetPath), error: responseError ?? error)
-        })
-        task.taskDescription = operation.json
-        task.resume()
-        return RemoteOperationHandle(operationType: operation, tasks: [task])
-    }
-    
-    func upload_simple(_ targetPath: String, localFile: URL, modifiedDate: Date = Date(), overwrite: Bool, operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let size = (try? localFile.resourceValues(forKeys: [.fileSizeKey]))?.fileSize ?? -1
+    func upload_simple(_ targetPath: String, data: Data? = nil, localFile: URL? = nil, modifiedDate: Date = Date(), overwrite: Bool, operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let size = data?.count ?? Int((try? localFile?.resourceValues(forKeys: [.fileSizeKey]))??.fileSize ?? -1)
         if size > 150 * 1024 * 1024 {
             let error = FileProviderDropboxError(code: .payloadTooLarge, path: targetPath, errorDescription: nil)
             completionHandler?(error)
             self.delegateNotify(.create(path: targetPath), error: error)
             return nil
         }
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        progress.totalUnitCount = Int64(size)
+        
         var requestDictionary = [String: AnyObject]()
         let url: URL
         url = URL(string: "files/upload", relativeTo: contentURL)!
         requestDictionary["path"] = correctPath(targetPath) as NSString?
         requestDictionary["mode"] = (overwrite ? "overwrite" : "add") as NSString
-        requestDictionary["client_modified"] = rfc3339utc(of: modifiedDate) as NSString
+        requestDictionary["client_modified"] = modifiedDate.rfc3339utc() as NSString
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/octet-stream", forHTTPHeaderField: "Content-Type")
-        request.setValue(String(jsonDictionary: requestDictionary), forHTTPHeaderField: "Dropbox-API-Arg")
-        let task = session.uploadTask(with: request, fromFile: localFile, completionHandler: { (data, response, error) in
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .stream)
+        request.set(dropboxArgKey: requestDictionary)
+        let task: URLSessionUploadTask
+        if let data = data {
+            task = session.uploadTask(with: request, from: data)
+        } else if let localFile = localFile {
+            task = session.uploadTask(with: request, fromFile: localFile)
+        } else {
+            return nil
+        }
+        
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { [weak self] error in
             var responseError: FileProviderDropboxError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderDropboxError(code: rCode, path: targetPath, errorDescription: String(data: data ?? Data(), encoding: .utf8))
+            if let code = (task.response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
+                // We can't fetch server result from delegate!
+                responseError = FileProviderDropboxError(code: rCode, path: targetPath, errorDescription: nil)
+            }
+            if !(responseError == nil && error == nil) {
+                progress.cancel()
             }
             completionHandler?(responseError ?? error)
-            self.delegateNotify(.create(path: targetPath), error: responseError ?? error)
-        })
+            self?.delegateNotify(.modify(path: targetPath), error: responseError ?? error)
+        }
         task.taskDescription = operation.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesSent), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: operation, tasks: [task])
+        return progress
     }
     
-    func search(_ startPath: String = "", query: String, start: Int = 0, maxResultPerPage: Int = 25, maxResults: Int = -1, foundItem:@escaping ((_ file: DropboxFileObject) -> Void), completionHandler: @escaping ((_ error: Error?) -> Void)) {
+    func search(_ startPath: String = "", query: String, start: Int = 0, maxResultPerPage: Int = 25, maxResults: Int = -1, progress: Progress, foundItem:@escaping ((_ file: DropboxFileObject) -> Void), completionHandler: @escaping ((_ error: Error?) -> Void)) {
+        if progress.isCancelled { return }
+        
         let url = URL(string: "files/search", relativeTo: apiURL)!
         var request = URLRequest(url: url)
         request.httpMethod = "POST"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .json)
         var requestDictionary: [String: AnyObject] = ["path": startPath as NSString]
         requestDictionary["query"] = query as NSString
         requestDictionary["start"] = start as NSNumber
@@ -206,12 +206,13 @@ internal extension DropboxFileProvider {
                     for entry in entries {
                         if let entry = entry as? [String: AnyObject], let file = DropboxFileObject(json: entry) {
                             foundItem(file)
+                            progress.completedUnitCount += 1
                         }
                     }
                     let rstart = json["start"] as? Int
                     let hasmore = (json["more"] as? NSNumber)?.boolValue ?? false
-                    if hasmore, let rstart = rstart {
-                        self.search(startPath, query: query, start: rstart + entries.count, maxResultPerPage: maxResultPerPage, foundItem: foundItem, completionHandler: completionHandler)
+                    if hasmore && !progress.isCancelled, let rstart = rstart {
+                        self.search(startPath, query: query, start: rstart + entries.count, maxResultPerPage: maxResultPerPage, progress: progress, foundItem: foundItem, completionHandler: completionHandler)
                     } else {
                         completionHandler(responseError ?? error)
                     }
@@ -219,7 +220,11 @@ internal extension DropboxFileProvider {
                 }
             }
             completionHandler(responseError ?? error)
-        }) 
+        })
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
     }
 }
@@ -241,11 +246,11 @@ internal extension DropboxFileProvider {
             DropboxFileProvider.decimalFormatter.numberStyle = .decimal
             DropboxFileProvider.decimalFormatter.maximumFractionDigits = 5
             keys.append("Location")
-            let latStr = DropboxFileProvider.decimalFormatter.string(from: NSNumber(value: latitude))
-            let longStr = DropboxFileProvider.decimalFormatter.string(from: NSNumber(value: longitude))
+            let latStr = DropboxFileProvider.decimalFormatter.string(from: NSNumber(value: latitude))!
+            let longStr = DropboxFileProvider.decimalFormatter.string(from: NSNumber(value: longitude))!
             dic["Location"] = "\(latStr), \(longStr)"
         }
-        if let timeTakenStr = json["time_taken"] as? String, let timeTaken = resolve(dateString: timeTakenStr) {
+        if let timeTakenStr = json["time_taken"] as? String, let timeTaken = Date(rfcString: timeTakenStr) {
             keys.append("Date taken")
             DropboxFileProvider.dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
             dic["Date taken"] = DropboxFileProvider.dateFormatter.string(from: timeTaken)

Sources/ExtendedLocalFileProvider.swift

@@ -12,7 +12,7 @@ import CoreGraphics
 import AVFoundation
 
 extension LocalFileProvider: ExtendedFileProvider {
-    public func thumbnailOfFileSupported(path: String) -> Bool {
+    open func thumbnailOfFileSupported(path: String) -> Bool {
         switch (path as NSString).pathExtension.lowercased() {
         case LocalFileInformationGenerator.imageThumbnailExtensions:
             return true
@@ -31,7 +31,7 @@ extension LocalFileProvider: ExtendedFileProvider {
         }
     }
     
-    public func propertiesOfFileSupported(path: String) -> Bool {
+    open func propertiesOfFileSupported(path: String) -> Bool {
         let fileExt = (path as NSString).pathExtension.lowercased()
         switch fileExt {
         case LocalFileInformationGenerator.imagePropertiesExtensions:
@@ -54,7 +54,7 @@ extension LocalFileProvider: ExtendedFileProvider {
         }
     }
     
-    public func thumbnailOfFile(path: String, dimension: CGSize? = nil, completionHandler: @escaping ((_ image: ImageClass?, _ error: Error?) -> Void)) {
+    open func thumbnailOfFile(path: String, dimension: CGSize? = nil, completionHandler: @escaping ((_ image: ImageClass?, _ error: Error?) -> Void)) {
         let dimension = dimension ?? CGSize(width: 64, height: 64)
         (dispatch_queue).async {
             var thumbnailImage: ImageClass? = nil
@@ -86,7 +86,7 @@ extension LocalFileProvider: ExtendedFileProvider {
         }
     }
     
-    public func propertiesOfFile(path: String, completionHandler: @escaping ((_ propertiesDictionary: [String: Any], _ keys: [String], _ error: Error?) -> Void)) {
+    open func propertiesOfFile(path: String, completionHandler: @escaping ((_ propertiesDictionary: [String: Any], _ keys: [String], _ error: Error?) -> Void)) {
         (dispatch_queue).async {
             let fileExt = (path as NSString).pathExtension.lowercased()
             var getter: ((_ fileURL: URL) -> (prop: [String: Any], keys: [String]))?
@@ -197,8 +197,13 @@ public struct LocalFileInformationGenerator {
     static public var audioThumbnail: (_ fileURL: URL) -> ImageClass? = { fileURL in
         let playerItem = AVPlayerItem(url: fileURL)
         let metadataList = playerItem.asset.commonMetadata
+        #if swift(>=4.0)
+        let commonKeyArtwork = AVMetadataKey.commonKeyArtwork
+        #else
+        let commonKeyArtwork = AVMetadataCommonKeyArtwork
+        #endif
         for item in metadataList {
-            if item.commonKey == AVMetadataCommonKeyArtwork {
+            if item.commonKey == commonKeyArtwork {
                 if let data = item.dataValue {
                     return ImageClass(data: data)
                 }
@@ -319,28 +324,34 @@ public struct LocalFileInformationGenerator {
             guard let key = key else {
                 return nil
             }
-            guard let regex = try? NSRegularExpression(pattern: "([a-z])([A-Z])" , options: NSRegularExpression.Options()) else {
+            guard let regex = try? NSRegularExpression(pattern: "([a-z])([A-Z])" , options: []) else {
                 return nil
             }
-            let newKey = regex.stringByReplacingMatches(in: key, options: NSRegularExpression.MatchingOptions(), range: NSMakeRange(0, (key as NSString).length) , withTemplate: "$1 $2")
+            let newKey = regex.stringByReplacingMatches(in: key, options: [], range: NSRange(location: 0, length: (key as NSString).length) , withTemplate: "$1 $2")
             return newKey.capitalized
         }
         
-        if FileManager.default.fileExists(atPath: fileURL.path) {
-            let playerItem = AVPlayerItem(url: fileURL)
-            let metadataList = playerItem.asset.commonMetadata
-            for item in metadataList {
-                if let description = makeDescription(item.commonKey) {
-                    if let value = item.stringValue {
-                        keys.append(description)
-                        dic[description] = value
-                    }
+        guard FileManager.default.fileExists(atPath: fileURL.path) else {
+            return (dic, keys)
+        }
+        let playerItem = AVPlayerItem(url: fileURL)
+        let metadataList = playerItem.asset.commonMetadata
+        for item in metadataList {
+            #if swift(>=4.0)
+                let commonKey = item.commonKey?.rawValue
+            #else
+                let commonKey = item.commonKey
+            #endif
+            if let description = makeDescription(commonKey) {
+                if let value = item.stringValue {
+                    keys.append(description)
+                    dic[description] = value
                 }
             }
-            if let ap = try? AVAudioPlayer(contentsOf: fileURL) {
-                add(key: "Duration", value: ap.duration.formatshort)
-                add(key: "Bitrate", value: ap.settings[AVSampleRateKey] as? Int)
-            }
+        }
+        if let ap = try? AVAudioPlayer(contentsOf: fileURL) {
+            add(key: "Duration", value: ap.duration.formatshort)
+            add(key: "Bitrate", value: ap.settings[AVSampleRateKey] as? Int)
         }
         return (dic, keys)
     }
@@ -366,7 +377,11 @@ public struct LocalFileInformationGenerator {
             }
         }
         let asset = AVURLAsset(url: fileURL, options: nil)
+        #if swift(>=4.0)
+        let videoTracks = asset.tracks(withMediaType: AVMediaType.video)
+        #else
         let videoTracks = asset.tracks(withMediaType: AVMediaTypeVideo)
+        #endif
         if let videoTrack = videoTracks.first {
             var bitrate: Float = 0
             let width = Int(videoTrack.naturalSize.width)
@@ -380,7 +395,11 @@ public struct LocalFileInformationGenerator {
             add(key: "Duration", value: TimeInterval(duration).formatshort)
             add(key: "Video Bitrate", value: "\(Int(ceil(bitrate / 1000))) kbps")
         }
+        #if swift(>=4.0)
+        let audioTracks = asset.tracks(withMediaType: AVMediaType.audio)
+        #else
         let audioTracks = asset.tracks(withMediaType: AVMediaTypeAudio)
+        #endif
         // dic["Audio channels"] = audioTracks.count
         var bitrate: Float = 0
         for track in audioTracks {
@@ -403,21 +422,40 @@ public struct LocalFileInformationGenerator {
         }
         
         func getKey(_ key: String, from dict: CGPDFDictionaryRef) -> String? {
-            var cfValue: CGPDFStringRef? = nil
-            if (CGPDFDictionaryGetString(dict, key, &cfValue)), let value = CGPDFStringCopyTextString(cfValue!) {
+            var cfStrValue: CGPDFStringRef?
+            if (CGPDFDictionaryGetString(dict, key, &cfStrValue)), let value = cfStrValue.flatMap({ CGPDFStringCopyTextString($0) }) {
                 return value as String
             }
+            var cfArrayValue: CGPDFArrayRef?
+            if (CGPDFDictionaryGetArray(dict, key, &cfArrayValue)), let cfArray = cfArrayValue {
+                var array = [String]()
+                for i in 0..<CGPDFArrayGetCount(cfArray) {
+                    var cfItemValue: CGPDFStringRef?
+                    if CGPDFArrayGetString(cfArray, i, &cfItemValue), let item = cfItemValue.flatMap({ CGPDFStringCopyTextString($0) }) {
+                        array.append(item as String)
+                    }
+                }
+                return array.joined(separator: ", ")
+            }
             return nil
         }
         
         func convertDate(_ date: String?) -> Date? {
             guard let date = date else { return nil }
-            var dateStr = date
+            var dateStr = date.replacingOccurrences(of: "'", with: "")
             if dateStr.hasPrefix("D:") {
-                dateStr = date.substring(from: date.characters.index(date.startIndex, offsetBy: 2))
+                dateStr.characters.removeFirst(2)
             }
             let dateFormatter = DateFormatter()
-            dateFormatter.dateFormat = "yyyyMMddHHmmssTZD"
+            dateFormatter.dateFormat = "yyyyMMddHHmmssTZ"
+            if let result = dateFormatter.date(from: dateStr) {
+                return result
+            }
+            dateFormatter.dateFormat = "yyyyMMddHHmmssZZZZZ"
+            if let result = dateFormatter.date(from: dateStr) {
+                return result
+            }
+            dateFormatter.dateFormat = "yyyyMMddHHmmssZ"
             if let result = dateFormatter.date(from: dateStr) {
                 return result
             }
@@ -428,29 +466,32 @@ public struct LocalFileInformationGenerator {
             return nil
         }
         
-        if let provider = CGDataProvider(url: fileURL as CFURL), let reference = CGPDFDocument(provider), let dict = reference.info {
-            add(key: "Title", value: getKey("Title", from: dict))
-            add(key: "Author", value: getKey("Author", from: dict))
-            add(key: "Subject", value: getKey("Subject", from: dict))
-            var majorVersion: Int32 = 0
-            var minorVersion: Int32 = 0
-            reference.getVersion(majorVersion: &majorVersion, minorVersion: &minorVersion)
-            if majorVersion > 0 {
-                add(key: "Version", value:  String(majorVersion) + "." + String(minorVersion))
-            }
-            add(key: "Pages", value: reference.numberOfPages)
-            
-            if reference.numberOfPages > 0, let pageRef = reference.page(at: 1) {
-                let size = pageRef.getBoxRect(CGPDFBox.mediaBox).size
-                add(key: "Resolution", value: "\(Int(size.width))x\(Int(size.height))")
-            }
-            add(key: "Content creator", value: getKey("Creator", from: dict))
-            add(key: "Creation date", value: convertDate(getKey("CreationDate", from: dict)))
-            add(key: "Modified date", value: convertDate(getKey("ModDate", from: dict)))
-            add(key: "Security", value: reference.isEncrypted ? "Present" : "None")
-            add(key: "Allows printing", value: reference.allowsPrinting ? "Yes" : "No")
-            add(key: "Allows copying", value: reference.allowsCopying ? "Yes" : "No")
+        guard let provider = CGDataProvider(url: fileURL as CFURL), let reference = CGPDFDocument(provider), let dict = reference.info else {
+            return (dic, keys)
         }
+        add(key: "Title", value: getKey("Title", from: dict))
+        add(key: "Author", value: getKey("Author", from: dict))
+        add(key: "Subject", value: getKey("Subject", from: dict))
+        add(key: "Producer", value: getKey("Producer", from: dict))
+        add(key: "Keywords", value: getKey("Keywords", from: dict))
+        var majorVersion: Int32 = 0
+        var minorVersion: Int32 = 0
+        reference.getVersion(majorVersion: &majorVersion, minorVersion: &minorVersion)
+        if majorVersion > 0 {
+            add(key: "Version", value:  String(majorVersion) + "." + String(minorVersion))
+        }
+        add(key: "Pages", value: reference.numberOfPages)
+        
+        if reference.numberOfPages > 0, let pageRef = reference.page(at: 1) {
+            let size = pageRef.getBoxRect(CGPDFBox.mediaBox).size
+            add(key: "Resolution", value: "\(Int(size.width))x\(Int(size.height))")
+        }
+        add(key: "Content creator", value: getKey("Creator", from: dict))
+        add(key: "Creation date", value: convertDate(getKey("CreationDate", from: dict)))
+        add(key: "Modified date", value: convertDate(getKey("ModDate", from: dict)))
+        add(key: "Security", value: reference.isEncrypted)
+        add(key: "Allows printing", value: reference.allowsPrinting)
+        add(key: "Allows copying", value: reference.allowsCopying)
         return (dic, keys)
     }
     

Sources/FTPFileProvider.swift

@@ -0,0 +1,887 @@
+//
+//  FTPFileProvider.swift
+//  FileProvider
+//
+//  Created by Amir Abbas Mousavian.
+//  Copyright © 2017 Mousavian. Distributed under MIT license.
+//
+
+import Foundation
+
+/**
+ Allows accessing to FTP files and directories. This provider doesn't cache or save files internally.
+ It's a complete reimplementation and doesn't use CFNetwork deprecated API.
+ */
+open class FTPFileProvider: FileProviderBasicRemote {
+    open class var type: String { return "FTP" }
+    open let baseURL: URL?
+    open var currentPath: String
+    
+    open var dispatch_queue: DispatchQueue
+    open var operation_queue: OperationQueue {
+        willSet {
+            assert(_session == nil, "It's not effective to change dispatch_queue property after session is initialized.")
+        }
+    }
+    
+    open weak var delegate: FileProviderDelegate?
+    open var credential: URLCredential? {
+        didSet {
+            sessionDelegate?.credential = self.credential
+        }
+    }
+    open private(set) var cache: URLCache?
+    public var useCache: Bool
+    public var validatingCache: Bool
+    
+    /// Determine either FTP session is in passive or active mode.
+    public let passiveMode: Bool
+    
+    /// Force to use URLSessionDownloadTask/URLSessionDataTask when possible
+    public var useAppleImplementation = true
+    
+    fileprivate var _session: URLSession?
+    internal var sessionDelegate: SessionDelegate?
+    public var session: URLSession {
+        get {
+            if _session == nil {
+                self.sessionDelegate = SessionDelegate(fileProvider: self)
+                let config = URLSessionConfiguration.default
+                config.urlCache = cache
+                config.requestCachePolicy = .returnCacheDataElseLoad
+                _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDelegate?, delegateQueue: self.operation_queue)
+                _session?.sessionDescription = UUID().uuidString
+                initEmptySessionHandler(_session!.sessionDescription!)
+            }
+            return _session!
+        }
+        
+        set {
+            assert(newValue.delegate is SessionDelegate, "session instances should have a SessionDelegate instance as delegate.")
+            _session = newValue
+            if session.sessionDescription?.isEmpty ?? true {
+                _session?.sessionDescription = UUID().uuidString
+            }
+            self.sessionDelegate = newValue.delegate as? SessionDelegate
+            initEmptySessionHandler(_session!.sessionDescription!)
+        }
+    }
+    
+    /**
+     Initializer for FTP provider with given username and password.
+     
+     - Note: `passive` value should be set according to server settings and firewall presence.
+     
+     - Parameter baseURL: a url with `ftp://hostaddress/` format.
+     - Parameter passive: FTP server data connection, `true` means passive connection (data connection created by client)
+         and `false` means active connection (data connection created by server). Default is `true` (passive mode).
+     - Parameter credential: a `URLCredential` object contains user and password.
+     - Parameter cache: A URLCache to cache downloaded files and contents. (unimplemented for FTP and should be nil)
+     */
+    public init? (baseURL: URL, passive: Bool = true, credential: URLCredential? = nil, cache: URLCache? = nil) {
+        guard (baseURL.scheme ?? "ftp").lowercased().hasPrefix("ftp") else { return nil }
+        guard baseURL.host != nil else { return nil }
+        var urlComponents = URLComponents(url: baseURL, resolvingAgainstBaseURL: true)!
+        let defaultPort: Int = baseURL.scheme == "ftps" ? 990 : 21
+        urlComponents.port = urlComponents.port ?? defaultPort
+        urlComponents.scheme = urlComponents.scheme ?? "ftp"
+        
+        self.baseURL =  (urlComponents.url!.path.hasSuffix("/") ? urlComponents.url! : urlComponents.url!.appendingPathComponent("")).absoluteURL
+        self.passiveMode = passive
+        self.currentPath = ""
+        self.useCache = false
+        self.validatingCache = true
+        self.cache = cache
+        self.credential = credential
+        
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
+        operation_queue = OperationQueue()
+        operation_queue.name = "\(queueLabel).Operation"
+    }
+    
+    public required convenience init?(coder aDecoder: NSCoder) {
+        guard let baseURL = aDecoder.decodeObject(forKey: "baseURL") as? URL else { return nil }
+        self.init(baseURL: baseURL, passive: aDecoder.decodeBool(forKey: "passiveMode"), credential: aDecoder.decodeObject(forKey: "credential") as? URLCredential)
+        self.currentPath     = aDecoder.decodeObject(forKey: "currentPath") as? String ?? ""
+        self.useCache        = aDecoder.decodeBool(forKey: "useCache")
+        self.validatingCache = aDecoder.decodeBool(forKey: "validatingCache")
+        self.useAppleImplementation = aDecoder.decodeBool(forKey: "useAppleImplementation")
+    }
+    
+    public func encode(with aCoder: NSCoder) {
+        aCoder.encode(self.baseURL, forKey: "baseURL")
+        aCoder.encode(self.credential, forKey: "credential")
+        aCoder.encode(self.currentPath, forKey: "currentPath")
+        aCoder.encode(self.useCache, forKey: "useCache")
+        aCoder.encode(self.validatingCache, forKey: "validatingCache")
+        aCoder.encode(self.useAppleImplementation, forKey: "useAppleImplementation")
+        aCoder.encode(self.passiveMode, forKey: "passiveMode")
+    }
+    
+    public static var supportsSecureCoding: Bool {
+        return true
+    }
+    
+    open func copy(with zone: NSZone? = nil) -> Any {
+        let copy = FTPFileProvider(baseURL: self.baseURL!, credential: self.credential, cache: self.cache)!
+        copy.currentPath = self.currentPath
+        copy.delegate = self.delegate
+        copy.fileOperationDelegate = self.fileOperationDelegate
+        copy.useCache = self.useCache
+        copy.validatingCache = self.validatingCache
+        copy.useAppleImplementation = self.useAppleImplementation
+        return copy
+    }
+    
+    deinit {
+        if let sessionuuid = _session?.sessionDescription {
+            removeSessionHandler(for: sessionuuid)
+        }
+        
+        if fileProviderCancelTasksOnInvalidating {
+            _session?.invalidateAndCancel()
+        } else {
+            _session?.finishTasksAndInvalidate()
+        }
+    }
+    
+    internal var serverSupportsRFC3659: Bool = true
+    
+    open func contentsOfDirectory(path: String, completionHandler: @escaping (([FileObject], Error?) -> Void)) {
+        self.contentsOfDirectory(path: path, rfc3659enabled: serverSupportsRFC3659, completionHandler: completionHandler)
+    }
+    
+    /**
+     Returns an Array of `FileObject`s identifying the the directory entries via asynchronous completion handler.
+     
+     If the directory contains no entries or an error is occured, this method will return the empty array.
+     
+     - Parameter path: path to target directory. If empty, `currentPath` value will be used.
+     - Parameter rfc3659enabled: uses MLST command instead of old LIST to get files attributes, default is `true`.
+     - Parameter completionHandler: a closure with result of directory entries or error.
+         `contents`: An array of `FileObject` identifying the the directory entries.
+         `error`: Error returned by system.
+     */
+    open func contentsOfDirectory(path apath: String, rfc3659enabled: Bool , completionHandler: @escaping ((_ contents: [FileObject], _ error: Error?) -> Void)) {
+        let path = ftpPath(apath)
+        
+        let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+        self.ftpLogin(task) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler([], error)
+                }
+                return
+            }
+            
+            self.ftpList(task, of: self.ftpPath(path), useMLST: rfc3659enabled, completionHandler: { (contents, error) in
+                defer {
+                    self.ftpQuit(task)
+                }
+                if let error = error {
+                    if ((error as NSError).domain == URLError.errorDomain && (error as NSError).code == URLError.unsupportedURL.rawValue) {
+                        self.contentsOfDirectory(path: path, rfc3659enabled: false, completionHandler: completionHandler)
+                        return
+                    }
+                    
+                    self.dispatch_queue.async {
+                        completionHandler([], error)
+                    }
+                    return
+                }
+                
+                
+                let files: [FileObject] = contents.flatMap {
+                    rfc3659enabled ? self.parseMLST($0, in: path) : self.parseUnixList($0, in: path)
+                }
+                
+                self.dispatch_queue.async {
+                    completionHandler(files, nil)
+                }
+            })
+        }
+    }
+    
+    open func attributesOfItem(path: String, completionHandler: @escaping ((FileObject?, Error?) -> Void)) {
+        self.attributesOfItem(path: path, rfc3659enabled: serverSupportsRFC3659, completionHandler: completionHandler)
+    }
+    
+    /**
+     Returns a `FileObject` containing the attributes of the item (file, directory, symlink, etc.) at the path in question via asynchronous completion handler.
+     
+     If the directory contains no entries or an error is occured, this method will return the empty `FileObject`.
+     
+     - Parameter path: path to target directory. If empty, `currentPath` value will be used.
+     - Parameter rfc3659enabled: uses MLST command instead of old LIST to get files attributes, default is true.
+     - Parameter completionHandler: a closure with result of directory entries or error.
+         `attributes`: A `FileObject` containing the attributes of the item.
+         `error`: Error returned by system.
+     */
+    open func attributesOfItem(path apath: String, rfc3659enabled: Bool, completionHandler: @escaping ((_ attributes: FileObject?, _ error: Error?) -> Void)) {
+        let path = ftpPath(apath)
+        
+        let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+        self.ftpLogin(task) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler(nil, error)
+                }
+                return
+            }
+            
+            let command = rfc3659enabled ? "MLST \(path)" : "LIST \(path)"
+            self.execute(command: command, on: task, completionHandler: { (response, error) in
+                defer {
+                    self.ftpQuit(task)
+                }
+                if let error = error {
+                    self.dispatch_queue.async {
+                        completionHandler(nil, error)
+                    }
+                    return
+                }
+                
+                guard let response = response, response.hasPrefix("250") || (response.hasPrefix("50") && rfc3659enabled) else {
+                    self.dispatch_queue.async {
+                        completionHandler(nil, self.throwError(path, code: URLError.badServerResponse))
+                    }
+                    return
+                }
+                
+                if response.hasPrefix("500") {
+                    self.serverSupportsRFC3659 = false
+                    self.attributesOfItem(path: path, rfc3659enabled: false, completionHandler: completionHandler)
+                }
+                
+                let lines = response.components(separatedBy: "\n").flatMap { $0.isEmpty ? nil : $0.trimmingCharacters(in: .whitespacesAndNewlines) }
+                guard lines.count > 2 else {
+                    self.dispatch_queue.async {
+                        completionHandler(nil, self.throwError(path, code: URLError.badServerResponse))
+                    }
+                    return
+                }
+                let file = rfc3659enabled ? self.parseMLST(lines[1], in: path) : self.parseUnixList(lines[1], in: path)
+                self.dispatch_queue.async {
+                    completionHandler(file, nil)
+                }
+            })
+        }
+    }
+    
+    open func storageProperties(completionHandler: @escaping ((_ total: Int64, _ used: Int64) -> Void)) {
+        dispatch_queue.async {
+            completionHandler(-1, 0)
+        }
+    }
+    
+    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
+        let progress = Progress(parent: nil, userInfo: nil)
+        _ = self.recursiveList(path: path, useMLST: true, foundItemsHandler: { items in
+            if let foundItemHandler = foundItemHandler {
+                for item in items where query.evaluate(with: item.mapPredicate()) {
+                    foundItemHandler(item)
+                }
+                progress.totalUnitCount = Int64(items.count)
+            }
+        }, completionHandler: {files, error in
+            if let error = error {
+                completionHandler([], error)
+                return
+            }
+            
+            let foundFiles = files.filter { query.evaluate(with: $0.mapPredicate()) }
+            completionHandler(foundFiles, nil)
+        })
+        return progress
+    }
+    
+    public func url(of path: String?) -> URL {
+        let path = (path ?? self.currentPath).trimmingCharacters(in: CharacterSet(charactersIn: "/ ")).addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? (path ?? self.currentPath)
+        
+        var baseUrlComponent = URLComponents(url: self.baseURL!, resolvingAgainstBaseURL: true)
+        baseUrlComponent?.user = credential?.user
+        baseUrlComponent?.password = credential?.password
+        return URL(string: path, relativeTo: baseUrlComponent?.url ?? baseURL) ?? baseUrlComponent?.url ?? baseURL!
+    }
+    
+    public func relativePathOf(url: URL) -> String {
+        // check if url derieved from current base url
+        let relativePath = url.relativePath
+        if !relativePath.isEmpty, url.baseURL == self.baseURL {
+            return (relativePath.removingPercentEncoding ?? relativePath).replacingOccurrences(of: "/", with: "", options: .anchored)
+        }
+        
+        if !relativePath.isEmpty, self.baseURL == self.url(of: "/") {
+            return (relativePath.removingPercentEncoding ?? relativePath).replacingOccurrences(of: "/", with: "", options: .anchored)
+        }
+        
+        return relativePath.replacingOccurrences(of: "/", with: "", options: .anchored)
+    }
+    
+    open func isReachable(completionHandler: @escaping (Bool) -> Void) {
+        self.attributesOfItem(path: "/") { (file, error) in
+            completionHandler(file != nil)
+        }
+    }
+    
+    open weak var fileOperationDelegate: FileOperationDelegate?
+}
+
+extension FTPFileProvider: FileProviderOperations {
+    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let path = (atPath as NSString).appendingPathComponent(folderName) + "/"
+        return doOperation(.create(path: path), completionHandler: completionHandler)
+    }
+    
+    open func moveItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return doOperation(.move(source: path, destination: toPath), completionHandler: completionHandler)
+    }
+    
+    open func copyItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return doOperation(.copy(source: path, destination: toPath), completionHandler: completionHandler)
+    }
+    
+    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
+        return doOperation(.remove(path: path), completionHandler: completionHandler)
+    }
+    
+    fileprivate func doOperation(_ opType: FileOperationType, completionHandler: SimpleCompletionHandler) -> Progress? {
+        guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
+            return nil
+        }
+        guard let sourcePath = opType.source else { return nil }
+        let destPath = opType.destination
+        
+        let command: String
+        switch opType {
+        case .create:
+            command = "MKD \(ftpPath(sourcePath))"
+        case .copy:
+            command = "SITE CPFR \(ftpPath(sourcePath))\r\nSITE CPTO \(ftpPath(destPath!))"
+        case .move:
+            command = "RNFR \(ftpPath(sourcePath))\r\nRNTO \(ftpPath(destPath!))"
+        case .remove:
+            command = "DELE \(ftpPath(sourcePath))"
+        case .link:
+            command = "SITE SYMLINK \(ftpPath(sourcePath)) \(ftpPath(destPath!))"
+        default: // modify, fetch
+            return nil
+        }
+        let progress = Progress(totalUnitCount: 1)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
+        let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+        self.ftpLogin(task) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+                return
+            }
+            
+            self.execute(command: command, on: task, completionHandler: { (response, error) in
+                if let error = error {
+                    self.dispatch_queue.async {
+                        completionHandler?(error)
+                        self.delegateNotify(opType, error: error)
+                    }
+                    return
+                }
+                
+                guard let response = response else {
+                    self.dispatch_queue.async {
+                        completionHandler?(error)
+                        self.delegateNotify(opType, error: self.throwError(sourcePath, code: URLError.badServerResponse))
+                    }
+                    return
+                }
+                
+                let codes: [Int] = response.components(separatedBy: .newlines).flatMap({ $0.isEmpty ? nil : $0})
+                .flatMap {
+                    let code = $0.components(separatedBy: .whitespaces).flatMap({ $0.isEmpty ? nil : $0}).first
+                    return code != nil ? Int(code!) : nil
+                }
+                
+                if codes.filter({ (450..<560).contains($0) }).count > 0 {
+                    let errorCode: URLError.Code
+                    switch opType {
+                    case .create:
+                        errorCode = URLError.cannotCreateFile
+                    case .modify:
+                        errorCode = URLError.cannotWriteToFile
+                    case .copy:
+                        self.fallbackCopy(opType, progress: progress, completionHandler: completionHandler)
+                        return
+                    case .move:
+                        errorCode = URLError.cannotMoveFile
+                    case .remove:
+                        self.fallbackRemove(opType, progress: progress, on: task, completionHandler: completionHandler)
+                        return
+                    case .link:
+                        errorCode = URLError.cannotWriteToFile
+                    default:
+                        errorCode = URLError.cannotOpenFile
+                    }
+                    let error = self.throwError(sourcePath, code: errorCode)
+                    progress.cancel()
+                    self.dispatch_queue.async {
+                        completionHandler?(error)
+                    }
+                    self.delegateNotify(opType, error: error)
+                    return
+                }
+                
+                progress.completedUnitCount = progress.totalUnitCount
+                self.dispatch_queue.async {
+                    completionHandler?(nil)
+                }
+                self.delegateNotify(opType, error: nil)
+            })
+        }
+        
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+        return progress
+    }
+    
+    private func fallbackCopy(_ opType: FileOperationType, progress: Progress, completionHandler: SimpleCompletionHandler) {
+        guard let sourcePath = opType.source else { return }
+        guard let destPath = opType.destination else { return }
+        
+        let localURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(UUID().uuidString).appendingPathExtension("tmp")
+        
+        progress.becomeCurrent(withPendingUnitCount: 1)
+        _ = self.copyItem(path: sourcePath, toLocalURL: localURL) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+                return
+            }
+            
+            progress.becomeCurrent(withPendingUnitCount: 1)
+            _ = self.copyItem(localFile: localURL, to: destPath) { error in
+                completionHandler?(nil)
+                self.delegateNotify(opType, error: nil)
+            }
+            progress.resignCurrent()
+        }
+        progress.resignCurrent()
+        return
+    }
+    
+    private func fallbackRemove(_ opType: FileOperationType, progress: Progress, on task: FileProviderStreamTask, completionHandler: SimpleCompletionHandler) {
+        guard let sourcePath = opType.source else { return }
+        
+        self.execute(command: "SITE RMDIR \(ftpPath(sourcePath))", on: task) { (response, error) in
+            if let error = error {
+                progress.cancel()
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                }
+                self.delegateNotify(opType, error: error)
+                return
+            }
+            
+            guard let response = response else {
+                progress.cancel()
+                let error = self.throwError(sourcePath, code: URLError.badServerResponse)
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                }
+                self.delegateNotify(opType, error: error)
+                return
+            }
+            
+            if response.hasPrefix("50") {
+                self.fallbackRecursiveRemove(opType, progress: progress, on: task, completionHandler: completionHandler)
+                return
+            }
+            
+            var error: Error?
+            if !response.hasPrefix("2") {
+                error = self.throwError(sourcePath, code: URLError.cannotRemoveFile)
+            }
+            self.dispatch_queue.async {
+                completionHandler?(error)
+            }
+            self.delegateNotify(opType, error: error)
+        }
+    }
+    
+    private func fallbackRecursiveRemove(_ opType: FileOperationType, progress: Progress, on task: FileProviderStreamTask, completionHandler: SimpleCompletionHandler) {
+        guard let sourcePath = opType.source else { return }
+        
+        _ = self.recursiveList(path: sourcePath, useMLST: true, completionHandler: { (contents, error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+                return
+            }
+            
+            let recursiveProgress = Progress(parent: progress, userInfo: nil)
+            recursiveProgress.totalUnitCount = Int64(contents.count)
+            let sortedContents = contents.sorted(by: {
+                $0.path.localizedStandardCompare($1.path) == .orderedDescending
+            })
+            var command = ""
+            for file in sortedContents {
+                command += (file.isDirectory ? "RMD \(self.ftpPath(file.path))" : "DELE \(self.ftpPath(file.path))") + "\r\n"
+            }
+            command += "RMD \(self.ftpPath(sourcePath))"
+            
+            self.execute(command: command, on: task, completionHandler: { (response, error) in
+                recursiveProgress.completedUnitCount += 1
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+                // TODO: Digest response
+            })
+        })
+    }
+    
+    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        // check file is not a folder
+        guard (try? localFile.resourceValues(forKeys: [.fileResourceTypeKey]))?.fileResourceType ?? .unknown == .regular else {
+            dispatch_queue.async {
+                completionHandler?(self.throwError(localFile.path, code: URLError.fileIsDirectory))
+            }
+            return nil
+        }
+        
+        let opType = FileOperationType.copy(source: localFile.absoluteString, destination: toPath)
+        guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
+            return nil
+        }
+        
+        let progress = Progress(totalUnitCount: 0)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
+        let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+        self.ftpLogin(task) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+                return
+            }
+            
+            self.ftpStore(task, filePath: self.ftpPath(toPath), fromData: nil, fromFile: localFile, onTask: { task in
+                weak var weakTask = task
+                progress.cancellationHandler = {
+                    weakTask?.cancel()
+                }
+                progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+            }, onProgress: { bytesSent, totalSent, expectedBytes in
+                progress.completedUnitCount = totalSent
+                DispatchQueue.main.async {
+                    self.delegate?.fileproviderProgress(self, operation: opType, progress: Float(progress.fractionCompleted))
+                }
+            }, completionHandler: { (error) in
+                if error != nil {
+                    progress.cancel()
+                }
+                self.ftpQuit(task)
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+            })
+        }
+        
+        return progress
+    }
+    
+    open func copyItem(path: String, toLocalURL destURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let opType = FileOperationType.copy(source: path, destination: destURL.absoluteString)
+        guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
+            return nil
+        }
+        var progress = Progress(totalUnitCount: 0)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
+        if self.useAppleImplementation {
+            self.attributesOfItem(path: path, completionHandler: { (file, error) in
+                if let error = error {
+                    self.dispatch_queue.async {
+                        completionHandler?(error)
+                        self.delegateNotify(opType, error: error)
+                    }
+                    return
+                }
+                
+                if file?.isDirectory ?? false {
+                    self.dispatch_queue.async {
+                        let error = self.throwError(path, code: URLError.fileIsDirectory)
+                        completionHandler?(error)
+                        self.delegateNotify(opType, error: error)
+                    }
+                    return
+                }
+                
+                progress.totalUnitCount = file?.size ?? 0
+                
+                let task = self.session.downloadTask(with: self.url(of: path))
+                completionHandlersForTasks[self.session.sessionDescription!]?[task.taskIdentifier] = completionHandler
+                downloadCompletionHandlersForTasks[self.session.sessionDescription!]?[task.taskIdentifier] = { tempURL in
+                    do {
+                        try FileManager.default.moveItem(at: tempURL, to: destURL)
+                        completionHandler?(nil)
+                    } catch let e {
+                        completionHandler?(e)
+                    }
+                }
+                task.taskDescription = opType.json
+                task.addObserver(self.sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+                task.addObserver(self.sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+                progress.cancellationHandler = { [weak task] in
+                    task?.cancel()
+                }
+                progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+                task.resume()
+            })
+        } else {
+            let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+            self.ftpLogin(task) { (error) in
+                if let error = error {
+                    self.dispatch_queue.async {
+                        completionHandler?(error)
+                    }
+                    return
+                }
+                
+                self.ftpRetrieveFile(task, filePath: self.ftpPath(path), onTask: { task in
+                    weak var weakTask = task
+                    progress.cancellationHandler = {
+                        weakTask?.cancel()
+                    }
+                    progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+                }, onProgress: { recevied, totalReceived, totalSize in
+                    progress.totalUnitCount = totalSize
+                    progress.completedUnitCount = totalReceived
+                    DispatchQueue.main.async {
+                        self.delegate?.fileproviderProgress(self, operation: opType, progress: Float(progress.fractionCompleted))
+                    }
+                }) { (tmpurl, error) in
+                    if let error = error {
+                        progress.cancel()
+                        self.dispatch_queue.async {
+                            completionHandler?(error)
+                            self.delegateNotify(opType, error: error)
+                        }
+                        return
+                    }
+                    
+                    if let tmpurl = tmpurl {
+                        try? FileManager.default.moveItem(at: tmpurl, to: destURL)
+                        self.dispatch_queue.async {
+                            completionHandler?(nil)
+                            self.delegateNotify(opType, error: nil)
+                        }
+                    }
+                }
+            }
+        }
+        return progress
+    }
+}
+
+extension FTPFileProvider: FileProviderReadWrite {
+    open func contents(path: String, completionHandler: @escaping ((Data?, Error?) -> Void)) -> Progress? {
+        let opType = FileOperationType.fetch(path: path)
+        guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
+            return nil
+        }
+        
+        if self.useAppleImplementation {
+            var progress = Progress(totalUnitCount: 0)
+            progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+            progress.kind = .file
+            progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+            
+            let task = session.downloadTask(with: url(of: path))
+            completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+                if error != nil {
+                    progress.cancel()
+                }
+                completionHandler(nil, error)
+            }
+            downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { tempURL in
+                do {
+                    let data = try Data(contentsOf: tempURL)
+                    completionHandler(data, nil)
+                } catch let e {
+                    completionHandler(nil, e)
+                }
+            }
+            task.taskDescription = opType.json
+            task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+            task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+            progress.cancellationHandler = { [weak task] in
+                task?.cancel()
+            }
+            progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+            task.resume()
+            return progress
+        } else {
+            return self.contents(path: path, offset: 0, length: -1, completionHandler: completionHandler)
+        }
+    }
+    
+    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
+        let opType = FileOperationType.fetch(path: path)
+        if length == 0 || offset < 0 {
+            dispatch_queue.async {
+                completionHandler(Data(), nil)
+                self.delegateNotify(opType, error: nil)
+            }
+            return nil
+        }
+        let progress = Progress(totalUnitCount: 0)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
+        let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+        self.ftpLogin(task) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler(nil, error)
+                }
+                return
+            }
+            
+            self.ftpRetrieveData(task, filePath: self.ftpPath(path), from: offset, length: length, onTask: { task in
+                weak var weakTask = task
+                progress.cancellationHandler = {
+                    weakTask?.cancel()
+                }
+                progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+            }, onProgress: { recevied, totalReceived, totalSize in
+                progress.totalUnitCount = totalSize
+                progress.completedUnitCount = totalReceived
+                DispatchQueue.main.async {
+                    self.delegate?.fileproviderProgress(self, operation: opType, progress: Float(progress.fractionCompleted))
+                }
+            }) { (data, error) in
+                if let error = error {
+                    progress.cancel()
+                    self.dispatch_queue.async {
+                        completionHandler(nil, error)
+                        self.delegateNotify(opType, error: error)
+                    }
+                    return
+                }
+                
+                if let data = data {
+                    self.dispatch_queue.async {
+                        completionHandler(data, nil)
+                        self.delegateNotify(opType, error: nil)
+                    }
+                }
+            }
+        }
+        
+        return progress
+    }
+    
+    open func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let opType = FileOperationType.modify(path: path)
+        guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
+            return nil
+        }
+        
+        let progress = Progress(totalUnitCount: Int64(data?.count ?? 0))
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
+        let task = session.fpstreamTask(withHostName: baseURL!.host!, port: baseURL!.port!)
+        self.ftpLogin(task) { (error) in
+            if let error = error {
+                self.dispatch_queue.async {
+                    completionHandler?(error)
+                    self.delegateNotify(opType, error: error)
+                }
+                return
+            }
+            
+            let storeHandler = {
+                self.ftpStore(task, filePath: self.ftpPath(path), fromData: data ?? Data(), fromFile: nil, onTask: { task in
+                    weak var weakTask = task
+                    progress.cancellationHandler = {
+                        weakTask?.cancel()
+                    }
+                    progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+                }, onProgress: { bytesSent, totalSent, expectedBytes in
+                    progress.completedUnitCount = totalSent
+                    DispatchQueue.main.async {
+                        self.delegate?.fileproviderProgress(self, operation: opType, progress: Float(progress.fractionCompleted))
+                    }
+                }, completionHandler: { (error) in
+                    if error != nil {
+                        progress.cancel()
+                    }
+                    self.ftpQuit(task)
+                    self.dispatch_queue.async {
+                        completionHandler?(error)
+                        self.delegateNotify(opType, error: error)
+                    }
+                })
+            }
+            
+            if overwrite {
+                storeHandler()
+            } else {
+                self.attributesOfItem(path: path, completionHandler: { (file, erroe) in
+                    if file == nil {
+                        storeHandler()
+                    }
+                })
+            }
+        }
+        
+        return progress
+    }
+}
+
+public extension FTPFileProvider {
+    /**
+     Creates a symbolic link at the specified path that points to an item at the given path.
+     This method does not traverse symbolic links contained in destination path, making it possible
+     to create symbolic links to locations that do not yet exist.
+     Also, if the final path component is a symbolic link, that link is not followed.
+     
+     - Note: Many servers does't support this functionality.
+     
+     - Parameters:
+       - symbolicLink: The file path at which to create the new symbolic link. The last component of the path issued as the name of the link.
+       - withDestinationPath: The path that contains the item to be pointed to by the link. In other words, this is the destination of the link.
+       - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
+     */
+    public func create(symbolicLink path: String, withDestinationPath destPath: String, completionHandler: SimpleCompletionHandler) {
+        let opType = FileOperationType.link(link: path, target: destPath)
+        _=self.doOperation(opType, completionHandler: completionHandler)
+    }
+}
+
+extension FTPFileProvider: FileProvider { }

Sources/FTPHelper.swift

@@ -0,0 +1,965 @@
+//
+//  FTPHelper.swift
+//  FileProvider
+//
+//  Created by Amir Abbas Mousavian.
+//  Copyright © 2017 Mousavian. Distributed under MIT license.
+//
+
+import Foundation
+
+internal extension FTPFileProvider {
+    func delegateNotify(_ operation: FileOperationType, error: Error?) {
+        DispatchQueue.main.async(execute: {
+            if error == nil {
+                self.delegate?.fileproviderSucceed(self, operation: operation)
+            } else {
+                self.delegate?.fileproviderFailed(self, operation: operation)
+            }
+        })
+    }
+    
+    func readDataUntilEOF(of task: FileProviderStreamTask, minLength: Int, receivedData: Data? = nil, timeout: TimeInterval, completionHandler: @escaping (_ data: Data?, _ errror:Error?) -> Void) {
+        task.readData(ofMinLength: minLength, maxLength: 65535, timeout: timeout) { (data, eof, error) in
+            if let error = error {
+                completionHandler(nil, error)
+                return
+            }
+            
+            var receivedData = receivedData
+            if let data = data {
+                if receivedData != nil {
+                    receivedData!.append(data)
+                } else {
+                    receivedData = data
+                }
+            }
+            
+            if eof {
+                completionHandler(receivedData, nil)
+            } else {
+                self.readDataUntilEOF(of: task, minLength: 0, receivedData: receivedData, timeout: timeout, completionHandler: completionHandler)
+            }
+            
+        }
+    }
+    
+    func execute(command: String, on task: FileProviderStreamTask, minLength: Int = 4, afterSend: ((_ error: Error?) -> Void)? = nil, completionHandler: @escaping (_ response: String?, _ error: Error?) -> Void) {
+        let timeout = session.configuration.timeoutIntervalForRequest
+        let terminalcommand = command + "\r\n"
+        task.write(terminalcommand.data(using: .utf8)!, timeout: timeout) { (error) in
+            if let error = error {
+                completionHandler(nil, error)
+                return
+            }
+            afterSend?(error)
+            
+            if task.state == .suspended {
+                task.resume()
+            }
+            
+            task.readData(ofMinLength: minLength, maxLength: 1024, timeout: timeout) { (data, eof, error) in
+                if let error = error {
+                    completionHandler(nil, error)
+                    return
+                }
+                
+                if let data = data, let response = String(data: data, encoding: .utf8) {
+                    completionHandler(response.trimmingCharacters(in: .whitespacesAndNewlines), nil)
+                } else {
+                    completionHandler(nil, self.throwError("", code: URLError.cannotParseResponse))
+                    return
+                }
+            }
+        }
+    }
+    
+    func ftpLogin(_ task: FileProviderStreamTask, completionHandler: @escaping (_ error: Error?) -> Void) {
+        let timeout = session.configuration.timeoutIntervalForRequest
+        if task.state == .suspended {
+            task.resume()
+        }
+        
+        var isSecure = false
+        // Implicit FTP Connection
+        if self.baseURL?.port == 990 || self.baseURL?.scheme == "ftps" {
+            task.startSecureConnection()
+            isSecure = true
+        }
+        
+        let credential = self.credential
+        
+        task.readData(ofMinLength: 4, maxLength: 2048, timeout: timeout) { (data, eof, error) in
+            if let error = error {
+                completionHandler(error)
+                return
+            }
+            
+            guard let data = data, let response = String(data: data, encoding: .utf8) else {
+                completionHandler(self.throwError("", code: URLError.cannotParseResponse))
+                return
+            }
+            
+            guard response.hasPrefix("22") else {
+                let error = FileProviderFTPError(message: response)
+                completionHandler(error)
+                return
+            }
+            
+            let loginHandle: () -> Void = {
+                self.execute(command: "USER \(credential?.user ?? "anonymous")", on: task) { (response, error) in
+                    if let error = error {
+                        completionHandler(error)
+                        return
+                    }
+                    
+                    guard let response = response else {
+                        completionHandler(self.throwError("", code: URLError.badServerResponse))
+                        return
+                    }
+                    
+                    // successfully logged in
+                    if response.hasPrefix("23") {
+                        completionHandler(nil)
+                        return
+                    }
+                    
+                    // needs password
+                    if FileProviderFTPError(message: response).code == 331 {
+                        self.execute(command: "PASS \(credential?.password ?? "fileprovider@")", on: task) { (response, error) in
+                            if response?.hasPrefix("23") ?? false {
+                                completionHandler(nil)
+                            } else {
+                                completionHandler(self.throwError("", code: URLError.userAuthenticationRequired))
+                            }
+                        }
+                        return
+                    }
+                    
+                    let error = FileProviderFTPError(message: response)
+                    completionHandler(error)
+                    return
+                }
+            }
+            
+            if !isSecure && self.baseURL?.scheme == "ftpes" {
+                // Explicit FTP Connection, by upgrading connection to FTP/SSL
+                self.execute(command: "AUTH TLS", on: task, minLength: 0, completionHandler: { (response, error) in
+                    if let error = error {
+                        completionHandler(error)
+                        return
+                    }
+                    
+                    if let response = response, response.hasPrefix("23") {
+                        task.startSecureConnection()
+                        isSecure = true
+                        self.execute(command: "PBSZ 0\r\nPROT P", on: task, completionHandler: { (response, error) in
+                            if let error = error {
+                                completionHandler(error)
+                                return
+                            }
+                            
+                            loginHandle()
+                        })
+                    }
+                })
+            } else if isSecure {
+                self.execute(command: "PBSZ 0\r\nPROT P", on: task, completionHandler: { (response, error) in
+                    if let error = error {
+                        completionHandler(error)
+                        return
+                    }
+                    
+                    loginHandle()
+                })
+            } else {
+                loginHandle()
+            }
+        }
+    }
+    
+    func ftpCwd(_ task: FileProviderStreamTask, to path: String, completionHandler: @escaping (_ error: Error?) -> Void) {
+        self.execute(command: "CWD \(path)", on: task) { (response, error) in
+            if let error = error {
+                completionHandler(error)
+                return
+            }
+            
+            guard let response = response else {
+                completionHandler(self.throwError(path, code: URLError.badServerResponse))
+                return
+            }
+            
+            // successfully logged in
+            if response.hasPrefix("25") {
+                completionHandler(nil)
+            }
+            // not logged in
+            else if response.hasPrefix("55") {
+                let error = FileProviderFTPError(message: response)
+                completionHandler(error)
+                return
+            }
+        }
+    }
+    
+    func ftpPassive(_ task: FileProviderStreamTask, completionHandler: @escaping (_ dataTask: FileProviderStreamTask?, _ error: Error?) -> Void) {
+        func trimmedNumber(_ s : String) -> String {
+            let characterSet = Set("+*#0123456789".characters)
+            return String(s.characters.lazy.filter(characterSet.contains))
+        }
+        
+        self.execute(command: "PASV", on: task) { (response, error) in
+            if let error = error {
+                completionHandler(nil, error)
+                return
+            }
+            
+            guard let response = response, let destString = response.components(separatedBy: " ").flatMap({ $0 }).last.flatMap({ String($0) }) else {
+                completionHandler(nil, self.throwError("", code: URLError.badServerResponse))
+                return
+            }
+            
+            let destArray = destString.components(separatedBy: ",").flatMap({ UInt32(trimmedNumber($0)) })
+            guard destArray.count == 6 else {
+                completionHandler(nil, self.throwError("", code: URLError.badServerResponse))
+                return
+            }
+            
+            // first 4 elements are ip, 2 next are port, as byte
+            var host = destArray.prefix(4).flatMap({ String($0) }).joined(separator: ".")
+            let port = Int(destArray[4] << 8 + destArray[5])
+            // IPv6 workaround
+            if host == "127.555.555.555" {
+                host = self.baseURL!.host!
+            }
+            
+            let passiveTask = self.session.fpstreamTask(withHostName: host, port: port)
+            passiveTask.resume()
+            if self.baseURL?.scheme == "ftps" || self.baseURL?.scheme == "ftpes" || self.baseURL?.port == 990 {
+                passiveTask.startSecureConnection()
+            }
+            completionHandler(passiveTask, nil)
+        }
+    }
+    
+    func ftpActive(_ task: FileProviderStreamTask, completionHandler: @escaping (_ dataTask: FileProviderStreamTask?, _ error: Error?) -> Void) {
+        let service = NetService(domain: "", type: "_tcp.", name: "", port: 0)
+        service.publish(options: .listenForConnections)
+        let startTime = Date()
+        while service.port < 1 && startTime.timeIntervalSinceNow > -self.session.configuration.timeoutIntervalForRequest {
+            usleep(100_000)
+        }
+        let activeTask = self.session.fpstreamTask(withNetService: service)
+        activeTask.resume()
+        if self.baseURL?.scheme == "ftps" || self.baseURL?.port == 990 {
+            activeTask.startSecureConnection()
+        }
+        
+        self.execute(command: "PORT \(service.port)", on: task) { (response, error) in
+            if let error = error {
+                activeTask.cancel()
+                completionHandler(nil, error)
+                return
+            }
+            
+            guard let response = response else {
+                activeTask.cancel()
+                completionHandler(nil, self.throwError("", code: URLError.badServerResponse))
+                return
+            }
+            
+            guard !response.hasPrefix("5") else {
+                activeTask.cancel()
+                completionHandler(nil, self.throwError("", code: URLError.cannotConnectToHost))
+                return
+            }
+            
+            completionHandler(activeTask, nil)
+        }
+    }
+    
+    func ftpDataConnect(_ task: FileProviderStreamTask, completionHandler: @escaping (_ dataTask: FileProviderStreamTask?, _ error: Error?) -> Void) {
+        if self.passiveMode {
+            self.ftpPassive(task, completionHandler: completionHandler)
+        } else {
+            dispatch_queue.async {
+                self.ftpActive(task, completionHandler: completionHandler)
+            }
+        }
+    }
+    
+    func ftpRest(_ task: FileProviderStreamTask, startPosition: Int64, completionHandler: @escaping (_ error: Error?) -> Void) {
+        self.execute(command: "REST \(startPosition)", on: task) { (response, error) in
+            if let error = error {
+                completionHandler(error)
+                return
+            }
+            
+            // Successful
+            guard let response = response else {
+                completionHandler(self.throwError("", code: URLError.badServerResponse))
+                return
+            }
+            
+            if response.hasPrefix("35") {
+                completionHandler(nil)
+            } else {
+                let error = FileProviderFTPError(message: response, path: "")
+                completionHandler(error)
+                return
+            }
+        }
+    }
+    
+    func ftpList(_ task: FileProviderStreamTask, of path: String, useMLST: Bool, completionHandler: @escaping (_ contents: [String], _ error: Error?) -> Void) {
+        self.ftpDataConnect(task) { (dataTask, error) in
+            if let error = error {
+                completionHandler([], error)
+                return
+            }
+            
+            guard let dataTask = dataTask else {
+                completionHandler([], self.throwError(path, code: URLError.badServerResponse))
+                return
+            }
+            
+            var success = false
+            let command = useMLST ? "MLSD \(path)" : "LIST \(path)"
+            self.execute(command: command, on: task, minLength: 20, afterSend: { error in
+                // starting passive task
+                let timeout = self.session.configuration.timeoutIntervalForRequest
+                
+                DispatchQueue.global().async {
+                    var finalData = Data()
+                    var eof = false
+                    var error: Error?
+                    while !eof {
+                        let group = DispatchGroup()
+                        group.enter()
+                        dataTask.readData(ofMinLength: 1, maxLength: 65535, timeout: timeout, completionHandler: { (data, seof, serror) in
+                            if let data = data {
+                                finalData.append(data)
+                            }
+                            eof = seof
+                            error = serror
+                            group.leave()
+                        })
+                        let waitResult = group.wait(timeout: .now() + timeout)
+                        
+                        if let error = error {
+                            if !((error as NSError).domain == URLError.errorDomain && (error as NSError).code == URLError.cancelled.rawValue) {
+                                completionHandler([], error)
+                            }
+                            return
+                        }
+                        
+                        if waitResult == .timedOut {
+                            completionHandler([], self.throwError(path, code: URLError.timedOut))
+                            return
+                        }
+                    }
+                    
+                    guard let response = String(data: finalData, encoding: .utf8) else {
+                        completionHandler([], self.throwError(path, code: URLError.badServerResponse))
+                        return
+                    }
+                    
+                    let contents: [String] = response.components(separatedBy: "\n").flatMap({ $0.trimmingCharacters(in: .whitespacesAndNewlines) })
+                    success = true
+                    completionHandler(contents, nil)
+                    return
+                }
+            }) { (response, error) in
+                if let error = error {
+                    completionHandler([], error)
+                    return
+                }
+                
+                guard let response = response else {
+                    completionHandler([], self.throwError(path, code: URLError.cannotParseResponse))
+                    return
+                }
+                
+                if response.hasPrefix("500") && useMLST {
+                    dataTask.cancel()
+                    self.serverSupportsRFC3659 = false
+                    completionHandler([], self.throwError(path, code: URLError.unsupportedURL))
+                    return
+                }
+                
+                if !success && !(response.hasPrefix("25") || response.hasPrefix("15")) {
+                    let error = FileProviderFTPError(message: response, path: path)
+                    self.dispatch_queue.async {
+                        completionHandler([], error)
+                    }
+                    return
+                }
+            }
+        }
+    }
+    
+    func recursiveList(path: String, useMLST: Bool, foundItemsHandler: ((_ contents: [FileObject]) -> Void)? = nil, completionHandler: @escaping (_ contents: [FileObject], _ error: Error?) -> Void) -> Progress? {
+        let progress = Progress(totalUnitCount: 0)
+        let queue = DispatchQueue(label: "\(self.type).recursiveList")
+        queue.async {
+            let group = DispatchGroup()
+            var result = [FileObject]()
+            var success = true
+            group.enter()
+            self.contentsOfDirectory(path: path, completionHandler: { (files, error) in
+                success = success && (error == nil)
+                if let error = error {
+                    completionHandler([], error)
+                    group.leave()
+                    return
+                }
+                
+                result.append(contentsOf: files)
+                progress.completedUnitCount = Int64(files.count)
+                foundItemsHandler?(files)
+                
+                let directories: [FileObject] = files.filter { $0.isDirectory }
+                progress.becomeCurrent(withPendingUnitCount: Int64(directories.count))
+                for dir in directories {
+                    group.enter()
+                    _=self.recursiveList(path: dir.path, useMLST: useMLST, foundItemsHandler: foundItemsHandler, completionHandler: { (contents, error) in
+                        success = success && (error == nil)
+                        if let error = error {
+                            completionHandler([], error)
+                            group.leave()
+                            return
+                        }
+                        
+                        foundItemsHandler?(files)
+                        result.append(contentsOf: contents)
+                        
+                        group.leave()
+                    })
+                }
+                progress.resignCurrent()
+                group.leave()
+            })
+            group.wait()
+            
+            if success {
+                self.dispatch_queue.async {
+                    completionHandler(result, nil)
+                }
+            }
+        }
+        return progress
+    }
+    
+    func ftpRetrieveData(_ task: FileProviderStreamTask, filePath: String, from position: Int64 = 0, length: Int = -1, onTask: ((_ task: FileProviderStreamTask) -> Void)?, onProgress: ((_ bytesReceived: Int64, _ totalReceived: Int64, _ expectedBytes: Int64) -> Void)?, completionHandler: @escaping (_ data: Data?, _ error: Error?) -> Void) {
+        
+        // Check cache
+        if useCache, let url = URL(string: filePath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? filePath, relativeTo: self.baseURL!)?.absoluteURL, let cachedResponse = self.cache?.cachedResponse(for: URLRequest(url: url)), cachedResponse.data.count > 0 {
+            dispatch_queue.async {
+                completionHandler(cachedResponse.data, nil)
+            }
+            return
+        }
+        
+        self.attributesOfItem(path: filePath) { (file, error) in
+            let totalSize = file?.size ?? -1
+            // Retreive data from server
+            self.ftpDataConnect(task) { (dataTask, error) in
+                if let error = error {
+                    completionHandler(nil, error)
+                    return
+                }
+                
+                guard let dataTask = dataTask else {
+                    completionHandler(nil, self.throwError(filePath, code: URLError.badServerResponse))
+                    return
+                }
+                
+                // Send retreive command
+                let len = 19 /* TYPE response */ + 65 + String(position).characters.count /* REST Response */ + 53 + filePath.characters.count + String(totalSize).characters.count /* RETR open response */ + 26 /* RETR Transfer complete message. */
+                self.execute(command: "TYPE I" + "\r\n" + "REST \(position)" + "\r\n" + "RETR \(filePath)", on: task, minLength: len, afterSend: { error in
+                    // starting passive task
+                    onTask?(dataTask)
+                    
+                    let timeout = self.session.configuration.timeoutIntervalForRequest
+                    DispatchQueue.global().async {
+                        var finalData = Data()
+                        var eof = false
+                        var error: Error?
+                        while !eof {
+                            let group = DispatchGroup()
+                            group.enter()
+                            dataTask.readData(ofMinLength: 0, maxLength: 65535, timeout: timeout, completionHandler: { (data, seof, serror) in
+                                if let data = data {
+                                    finalData.append(data)
+                                    onProgress?(Int64(data.count), Int64(finalData.count), totalSize)
+                                }
+                                eof = seof || (length > 0 && finalData.count >= length)
+                                if length > 0 && finalData.count > length {
+                                    finalData.count = length
+                                }
+                                error = serror
+                                group.leave()
+                            })
+                            let waitResult = group.wait(timeout: .now() + timeout)
+                            
+                            if let error = error {
+                                completionHandler(nil, error)
+                                return
+                            }
+                            
+                            if waitResult == .timedOut {
+                                completionHandler(nil, self.throwError(filePath, code: URLError.timedOut))
+                                return
+                            }
+                        }
+                        
+                        if let url = URL(string: filePath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? filePath, relativeTo: self.baseURL!)?.absoluteURL {
+                            let urlresponse = URLResponse(url: url, mimeType: nil, expectedContentLength: finalData.count, textEncodingName: nil)
+                            let cachedResponse = CachedURLResponse(response: urlresponse, data: finalData)
+                            let request = URLRequest(url: url)
+                            self.cache?.storeCachedResponse(cachedResponse, for: request)
+                        }
+                        
+                        completionHandler(finalData, nil)
+                        return
+                    }
+                }) { (response, error) in
+                    if let error = error {
+                        completionHandler(nil, error)
+                        return
+                    }
+                    
+                    guard let response = response else {
+                        completionHandler(nil, self.throwError(filePath, code: URLError.cannotParseResponse))
+                        return
+                    }
+                    
+                    if !(response.hasPrefix("1") || !response.hasPrefix("2")) {
+                        let error = FileProviderFTPError(message: response)
+                        
+                        self.dispatch_queue.async {
+                            completionHandler(nil, error)
+                        }
+                        return
+                    }
+                }
+            }
+        }
+    }
+    
+    func ftpRetrieveFile(_ task: FileProviderStreamTask, filePath: String, from position: Int64 = 0, length: Int = -1, onTask: ((_ task: FileProviderStreamTask) -> Void)?, onProgress: ((_ bytesReceived: Int64, _ totalReceived: Int64, _ expectedBytes: Int64) -> Void)?, completionHandler: @escaping (_ file: URL?, _ error: Error?) -> Void) {
+        let tempURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(UUID().uuidString).appendingPathExtension("tmp")
+        
+        // Check cache
+        if useCache, let url = URL(string: filePath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? filePath, relativeTo: self.baseURL!)?.absoluteURL, let cachedResponse = self.cache?.cachedResponse(for: URLRequest(url: url)), cachedResponse.data.count > 0 {
+            dispatch_queue.async {
+                do {
+                    try cachedResponse.data.write(to: tempURL)
+                    completionHandler(tempURL, nil)
+                } catch {
+                    completionHandler(nil, error)
+                }
+                try? FileManager.default.removeItem(at: tempURL)
+            }
+            return
+        }
+        
+        self.attributesOfItem(path: filePath) { (file, error) in
+            let totalSize = file?.size ?? -1
+            // Retreive data from server
+            self.ftpDataConnect(task) { (dataTask, error) in
+                if let error = error {
+                    completionHandler(nil, error)
+                    return
+                }
+                
+                guard let dataTask = dataTask else {
+                    completionHandler(nil, self.throwError(filePath, code: URLError.badServerResponse))
+                    return
+                }
+                
+                // Send retreive command
+                let len = 19 /* TYPE response */ + 65 + String(position).characters.count /* REST Response */ + 53 + filePath.characters.count + String(totalSize).characters.count /* RETR open response */ + 26 /* RETR Transfer complete message. */
+                self.execute(command: "TYPE I"  + "\r\n" + "REST \(position)" + "\r\n" + "RETR \(filePath)", on: task, minLength: len, afterSend: { error in
+                    // starting passive task
+                    onTask?(dataTask)
+                    
+                    let timeout = self.session.configuration.timeoutIntervalForRequest
+                    DispatchQueue.global().async {
+                        var finalData = Data()
+                        var eof = false
+                        var error: Error?
+                        while !eof {
+                            let group = DispatchGroup()
+                            group.enter()
+                            dataTask.readData(ofMinLength: 0, maxLength: 65535, timeout: timeout, completionHandler: { (data, seof, serror) in
+                                if let data = data {
+                                    finalData.append(data)
+                                    onProgress?(Int64(data.count), Int64(finalData.count), totalSize)
+                                }
+                                eof = seof || (length > 0 && finalData.count >= length)
+                                if length > 0 && finalData.count > length {
+                                    finalData.count = length
+                                }
+                                error = serror
+                                group.leave()
+                            })
+                            let waitResult = group.wait(timeout: .now() + timeout)
+                            
+                            if let error = error {
+                                completionHandler(nil, error)
+                                return
+                            }
+                            
+                            if waitResult == .timedOut {
+                                error = self.throwError("", code: URLError.timedOut)
+                                completionHandler(nil, error)
+                                return
+                            }
+                        }
+                        
+                        if let url = URL(string: filePath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? filePath, relativeTo: self.baseURL!)?.absoluteURL {
+                            let urlresponse = URLResponse(url: url, mimeType: nil, expectedContentLength: finalData.count, textEncodingName: nil)
+                            let cachedResponse = CachedURLResponse(response: urlresponse, data: finalData)
+                            let request = URLRequest(url: url)
+                            self.cache?.storeCachedResponse(cachedResponse, for: request)
+                        }
+                        
+                        self.dispatch_queue.async {
+                            do {
+                                try finalData.write(to: tempURL)
+                                completionHandler(tempURL, nil)
+                            } catch {
+                                completionHandler(nil, error)
+                            }
+                            try? FileManager.default.removeItem(at: tempURL)
+                        }
+                        return
+                    }
+                }) { (response, error) in
+                    if let error = error {
+                        completionHandler(nil, error)
+                        return
+                    }
+                    
+                    guard let response = response else {
+                        completionHandler(nil, self.throwError(filePath, code: URLError.cannotParseResponse))
+                        return
+                    }
+                    
+                    if !(response.hasPrefix("1") || response.hasPrefix("2")) {
+                        let error = FileProviderFTPError(message: response)
+                        
+                        self.dispatch_queue.async {
+                            completionHandler(nil, error)
+                        }
+                        return
+                    }
+                }
+            }
+        }
+    }
+    
+    func ftpStore(_ task: FileProviderStreamTask, filePath: String, fromData: Data?, fromFile: URL?, onTask: ((_ task: FileProviderStreamTask) -> Void)?,  onProgress: ((_ bytesSent: Int64, _ totalSent: Int64, _ expectedBytes: Int64) -> Void)?, completionHandler: @escaping (_ error: Error?) -> Void) {
+        let timeout = self.session.configuration.timeoutIntervalForRequest
+        operation_queue.addOperation {
+            guard let size: Int64 = (fromData != nil ? Int64(fromData!.count) : nil) ?? fromFile?.fileSize else { return }
+            
+            var error: Error?
+            let chunkSize: Int
+            switch size {
+            case 0..<262_144: chunkSize = 32_768 // 0KB To 256KB, page size is 32KB
+            case 262_144..<1_048_576: chunkSize = 65_536 // 256KB To 1MB, page size is 64KB
+            case 1_048_576..<10_485_760: chunkSize = 131_072 // 1MB To 10MB, page size is 128KB
+            case 10_048_576..<33_554_432: chunkSize = 262_144 // 1MB To 10MB, page size is 256KB
+            default: chunkSize = 524_288 // Larger than 32MB, page size is 512KB
+            }
+            
+            var fileHandle: FileHandle?
+            if let file = fromFile {
+                fileHandle = FileHandle(forReadingAtPath: file.path)
+            }
+            defer {
+                fileHandle?.closeFile()
+            }
+            
+            var eof = false
+            var sent: Int64 = 0
+            
+            while !eof {
+                let subdata: Data
+                if let data = fromData {
+                    let endIndex = min(data.count, Int(sent) + chunkSize)
+                    eof = endIndex == data.count
+                    subdata = data.subdata(in: Int(sent)..<endIndex)
+                }else if let fileHandle = fileHandle {
+                    subdata = fileHandle.readData(ofLength: chunkSize)
+                    eof = Int64(fileHandle.offsetInFile) == size
+                } else {
+                    return
+                }
+                if subdata.count == 0 { continue }
+                
+                let group = DispatchGroup()
+                group.enter()
+                self.ftpStore(task, data: subdata, to: filePath, from: sent, onTask: onTask, completionHandler: { (serror) in
+                    error = serror
+                    sent += Int64(subdata.count)
+                    group.leave()
+                    onProgress?(Int64(subdata.count), sent, size)
+                })
+                let waitResult = group.wait(timeout: .now() + timeout)
+                
+                if waitResult == .timedOut {
+                    error = self.throwError(filePath, code: URLError.timedOut)
+                    completionHandler(error)
+                    return
+                }
+                if let error = error {
+                    completionHandler(error)
+                    return
+                }
+            }
+            completionHandler(nil)
+        }
+    }
+    
+    func ftpStore(_ task: FileProviderStreamTask, data: Data, to filePath: String, from position: Int64, onTask: ((_ task: FileProviderStreamTask) -> Void)?, completionHandler: @escaping (_ error: Error?) -> Void) {
+        self.ftpDataConnect(task) { (dataTask, error) in
+            if let error = error {
+                completionHandler(error)
+                return
+            }
+            
+            guard let dataTask = dataTask else {
+                completionHandler(self.throwError(filePath, code: URLError.badServerResponse))
+                return
+            }
+            
+            // Send retreive command
+            var success = false
+            let len = 19 /* TYPE response */ + 65 + String(position).characters.count /* REST Response */ + 44 + filePath.characters.count /* STOR open response */ + 10 /* RETR Transfer complete message. */
+            self.execute(command: "TYPE I"  + "\r\n" + "REST \(position)"  + "\r\n" + "STOR \(filePath)", on: task, minLength: len, afterSend: { error in
+                // starting passive task
+                let timeout = self.session.configuration.timeoutIntervalForRequest
+                if self.baseURL?.scheme == "ftps" || self.baseURL?.port == 990 {
+                    task.startSecureConnection()
+                }
+                onTask?(dataTask)
+                
+                if data.count == 0 { return }
+                
+                dataTask.write(data, timeout: timeout, completionHandler: { (error) in
+                    if let error = error {
+                        completionHandler(error)
+                        return
+                    }
+                    success = true
+                    
+                    dataTask.closeRead()
+                    dataTask.closeWrite()
+                })
+            }) { (response, error) in
+                guard success else { return }
+                
+                if let error = error {
+                    completionHandler(error)
+                    return
+                }
+                
+                guard let response = response else {
+                    completionHandler(self.throwError(filePath, code: URLError.cannotParseResponse))
+                    return
+                }
+                
+                if !(response.hasPrefix("1") || response.hasPrefix("2")) {
+                    let error = FileProviderFTPError(message: response)
+                    
+                    self.dispatch_queue.async {
+                        completionHandler(error)
+                    }
+                    return
+                }
+                
+                completionHandler(nil)
+            }
+        }
+    }
+    
+    func ftpQuit(_ task: FileProviderStreamTask) {
+        self.execute(command: "QUIT", on: task) { (_, _) in
+            //task.closeRead()
+            //task.closeWrite()
+        }
+    }
+    
+    func ftpPath(_ apath: String) -> String {
+        var path = apath.isEmpty ? self.currentPath : apath
+        
+        // path of base url should be concreted into file path!
+        path = baseURL!.appendingPathComponent(path).path
+        
+        // Fixing slashes
+        if !path.hasPrefix("/") {
+            path = "/" + path
+        }
+        if path.hasSuffix("/"){
+            path.characters.removeLast()
+        }
+        
+        if path.isEmpty {
+            path = "/"
+        }
+        
+        return path
+    }
+    
+    func parseUnixList(_ text: String, in path: String) -> FileObject? {
+        let gregorian = Calendar(identifier: .gregorian)
+        let nearDateFormatter = DateFormatter()
+        nearDateFormatter.calendar = gregorian
+        nearDateFormatter.locale = Locale(identifier: "en_US_POSIX")
+        nearDateFormatter.dateFormat = "MMM dd hh:ss yyyy"
+        let farDateFormatter = DateFormatter()
+        farDateFormatter.calendar = gregorian
+        farDateFormatter.locale = Locale(identifier: "en_US_POSIX")
+        farDateFormatter.dateFormat = "MMM dd yyyy"
+        let thisYear = gregorian.component(.year, from: Date())
+        
+        let components = text.components(separatedBy: " ").flatMap { $0.isEmpty ? nil : $0 }
+        guard components.count >= 9 else { return nil }
+        let posixPermission = components[0]
+        let linksCount = Int(components[1]) ?? 0
+        //let owner = components[2]
+        //let groupOwner = components[3]
+        let size = Int64(components[4]) ?? -1
+        let date = components[5..<8].joined(separator: " ")
+        let name = components[8..<components.count].joined(separator: " ")
+        
+        guard name != "." && name != ".." else { return nil }
+        var path = (path as NSString).appendingPathComponent(name)
+        if path.hasPrefix("/") {
+            path.characters.removeFirst()
+        }
+        
+        let file = FileObject(url: url(of: path), name: name, path: path)
+        switch String(posixPermission.characters.first!) {
+        case "d": file.type = .directory
+        case "l": file.type = .symbolicLink
+        default:  file.type = .regular
+        }
+        file.isReadOnly = !posixPermission.contains("w")
+        file.size = file.isDirectory ? -1 : size
+        file.allValues[.linkCountKey] = linksCount
+        
+        if let parsedDate = nearDateFormatter.date(from: date + " " + String(thisYear)) {
+            if parsedDate > Date() {
+                file.modifiedDate = gregorian.date(byAdding: .year, value: -1, to: parsedDate)
+            } else {
+                file.modifiedDate = parsedDate
+            }
+        } else if let parsedDate = farDateFormatter.date(from: date) {
+            file.modifiedDate = parsedDate
+        }
+        
+        return file
+    }
+    
+    func parseMLST(_ text: String, in path: String) -> FileObject? {
+        var components = text.components(separatedBy: ";").flatMap { $0.isEmpty ? nil : $0 }
+        guard components.count > 1 else { return nil }
+        
+        let nameOrPath = components.removeLast().trimmingCharacters(in: .whitespacesAndNewlines)
+        var correctedPath: String
+        let name: String
+        if nameOrPath.hasPrefix("/") {
+            correctedPath = nameOrPath.replacingOccurrences(of: baseURL!.path, with: "", options: .anchored)
+            name = (nameOrPath as NSString).lastPathComponent
+        } else {
+            name = nameOrPath
+            correctedPath = (path as NSString).appendingPathComponent(nameOrPath)
+        }
+        if correctedPath.hasPrefix("/") {
+            correctedPath.characters.removeFirst()
+        }
+        
+        var attributes = [String: String]()
+        for component in components {
+            let keyValue = component.components(separatedBy: "=") .flatMap { $0.isEmpty ? nil : $0 }
+            guard keyValue.count >= 2, !keyValue[0].isEmpty else { continue }
+            attributes[keyValue[0].lowercased()] = keyValue.dropFirst().joined(separator: "=")
+        }
+        
+        let file = FileObject(url: url(of: correctedPath), name: name, path: correctedPath)
+        let dateFormatter = DateFormatter()
+        dateFormatter.calendar = Calendar(identifier: .gregorian)
+        dateFormatter.locale = Locale(identifier: "en_US_POSIX")
+        dateFormatter.dateFormat = "yyyyMMddhhmmss"
+        for (key, attribute) in attributes {
+            switch key {
+            case "type":
+                switch attribute.lowercased() {
+                case "file": file.type = .regular
+                case "dir": file.type = .directory
+                case "link": file.type = .symbolicLink
+                case "os.unix=block": file.type = .blockSpecial
+                case "cdir", "pdir": return nil // . and .. files are redundant in listing
+                default: file.type = .unknown
+                }
+                
+            case "unique":
+                file.allValues[.fileResourceIdentifierKey] = attribute
+                
+            case "modify":
+                file.modifiedDate = dateFormatter.date(from: attribute)
+            
+            case "create":
+                file.creationDate = dateFormatter.date(from: attribute)
+                
+            case "perm":
+                file.allValues[.isReadableKey] = attribute.contains("r") || attribute.contains("l")
+                file.allValues[.isWritableKey] = attribute.contains("w") || attribute.contains("a")
+                
+            case "size":
+                file.size = Int64(attribute) ?? -1
+                
+            case "media-type":
+                file.allValues[.mimeTypeKey] = attribute
+                
+            default:
+                break
+            }
+        }
+        
+        return file
+    }
+}
+
+/// Contains error code and description returned by FTP/S provider.
+public struct FileProviderFTPError: Error {
+    /// HTTP status code returned for error by server.
+    public let code: Int
+    /// Path of file/folder casued that error
+    public let path: String
+    /// Contents returned by server as error description
+    public let errorDescription: String?
+    
+    init(code: Int, path: String, errorDescription: String?) {
+        self.code = code
+        self.path = path
+        self.errorDescription = errorDescription
+    }
+    
+    init(message response: String, path: String = "") {
+        let message = response.components(separatedBy: .newlines).last ?? "No Response"
+        let spaceIndex = message.characters.index(of: "-") ?? message.characters.index(of: " ") ?? message.startIndex
+        self.code = Int(message.substring(to: spaceIndex).trimmingCharacters(in: .whitespacesAndNewlines)) ?? -1
+        self.path = path
+        if code > 0 {
+            self.errorDescription = message.substring(from: spaceIndex).trimmingCharacters(in: .whitespacesAndNewlines)
+        } else {
+            self.errorDescription = message
+        }
+    }
+}

Sources/FileObject.swift

@@ -13,31 +13,32 @@ open class FileObject: Equatable {
     /// A `Dictionary` contains file information,  using `URLResourceKey` keys.
     open internal(set) var allValues: [URLResourceKey: Any]
     
-    internal init(allValues: [URLResourceKey: Any]) {
+    public init(allValues: [URLResourceKey: Any]) {
         self.allValues = allValues
     }
     
-    internal init(url: URL, name: String, path: String) {
+    internal init(url: URL?, name: String, path: String) {
         self.allValues = [URLResourceKey: Any]()
-        self.url = url
+        if let url = url {
+            self.url = url
+        }
         self.name = name
         self.path = path
     }
     
-    /// url to access the resource, not supported by Dropbox provider
-    @available(*, obsoleted: 1.0, renamed: "url", message: "Use url.absoluteURL instead.")
-    open var absoluteURL: URL? {
-        return url?.absoluteURL
-    }
-    
     /// URL to access the resource, can be a relative URL against base URL.
     /// not supported by Dropbox provider.
-    open internal(set) var url: URL? {
+    open internal(set) var url: URL {
         get {
-            return allValues[.fileURL] as? URL
+            if let url = allValues[.fileURLKey] as? URL {
+                return url
+            } else {
+                let path = self.path.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? self.path
+                return URL(string: path) ?? URL(string: "/")!
+            }
         }
         set {
-            allValues[.fileURL] = newValue
+            allValues[.fileURLKey] = newValue
         }
     }
     
@@ -139,21 +140,28 @@ open class FileObject: Equatable {
     
     /// Check `FileObject` equality
     public static func ==(lhs: FileObject, rhs: FileObject) -> Bool {
-        if rhs === lhs {
+        if rhs === lhs  {
             return true
         }
+        #if swift(>=3.1)
+        if Swift.type(of: lhs) != Swift.type(of: rhs) {
+            return false
+        }
+        #else
         if type(of: lhs) != type(of: rhs) {
             return false
         }
-        if let rurl = rhs.url, let lurl = lhs.url {
+        #endif
+        
+        if let rurl = rhs.allValues[.fileURLKey] as? URL, let lurl = lhs.allValues[.fileURLKey] as? URL {
             return rurl == lurl
         }
         return rhs.path == lhs.path && rhs.size == lhs.size && rhs.modifiedDate == lhs.modifiedDate
     }
     
     internal func mapPredicate() -> [String: Any] {
-        let mapDict: [URLResourceKey: String] = [.fileURL: "url", .nameKey: "name", .pathKey: "path", .fileSizeKey: "filesize", .creationDateKey: "creationDate",
-                                                 .contentModificationDateKey: "modifiedDate", .isHiddenKey: "isHidden", .isWritableKey: "isWritable", .serverDate: "serverDate", .entryTag: "entryTag", .mimeType: "mimeType"]
+        let mapDict: [URLResourceKey: String] = [.fileURLKey: "url", .nameKey: "name", .pathKey: "path", .fileSizeKey: "filesize", .creationDateKey: "creationDate",
+                                                 .contentModificationDateKey: "modifiedDate", .isHiddenKey: "isHidden", .isWritableKey: "isWritable", .serverDateKey: "serverDate", .entryTagKey: "entryTag", .mimeTypeKey: "mimeType"]
         let typeDict: [URLFileResourceType: String] = [.directory: "directory", .regular: "regular", .symbolicLink: "symbolicLink", .unknown: "unknown"]
         var result = [String: Any]()
         for (key, value) in allValues {
@@ -170,10 +178,11 @@ open class FileObject: Equatable {
         return result
     }
     
+    /// Converts macOS spotlight query for searching files to a query that can be used for `searchFiles()` method
     static public func convertPredicate(fromSpotlight query: NSPredicate) -> NSPredicate {
-        let mapDict: [String: URLResourceKey] = [NSMetadataItemURLKey: .fileURL, NSMetadataItemFSNameKey: .nameKey, NSMetadataItemPathKey: .pathKey,
+        let mapDict: [String: URLResourceKey] = [NSMetadataItemURLKey: .fileURLKey, NSMetadataItemFSNameKey: .nameKey, NSMetadataItemPathKey: .pathKey,
                                                  NSMetadataItemFSSizeKey: .fileSizeKey, NSMetadataItemFSCreationDateKey: .creationDateKey,
-                                                 NSMetadataItemFSContentChangeDateKey: .contentModificationDateKey, "kMDItemFSInvisible": .isHiddenKey, "kMDItemFSIsWriteable": .isWritableKey, "kMDItemKind": .mimeType]
+                                                 NSMetadataItemFSContentChangeDateKey: .contentModificationDateKey, "kMDItemFSInvisible": .isHiddenKey, "kMDItemFSIsWriteable": .isWritableKey, "kMDItemKind": .mimeTypeKey]
         
         if let cQuery = query as? NSCompoundPredicate {
             let newSub = cQuery.subpredicates.map { convertPredicate(fromSpotlight: $0 as! NSPredicate) }
@@ -198,37 +207,6 @@ open class FileObject: Equatable {
     }
 }
 
-internal func resolve(dateString: String) -> Date? {
-    let dateFor: DateFormatter = DateFormatter()
-    dateFor.locale = Locale(identifier: "en_US")
-    dateFor.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ssZ"
-    if let rfc3339 = dateFor.date(from: dateString) {
-        return rfc3339
-    }
-    dateFor.dateFormat = "EEE',' dd' 'MMM' 'yyyy HH':'mm':'ss z"
-    if let rfc1123 = dateFor.date(from: dateString) {
-        return rfc1123
-    }
-    dateFor.dateFormat = "EEEE',' dd'-'MMM'-'yy HH':'mm':'ss z"
-    if let rfc850 = dateFor.date(from: dateString) {
-        return rfc850
-    }
-    dateFor.dateFormat = "EEE MMM d HH':'mm':'ss yyyy"
-    if let asctime = dateFor.date(from: dateString) {
-        return asctime
-    }
-    
-    return nil
-}
-
-internal func rfc3339utc(of date:Date) -> String {
-    let fm = DateFormatter()
-    fm.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"
-    fm.timeZone = TimeZone(identifier:"UTC")
-    fm.locale = Locale(identifier:"en_US_POSIX")
-    return fm.string(from:date)
-}
-
 /// Sorting FileObject array by given criteria, **not thread-safe**
 public struct FileObjectSorting {
     

Sources/FileProvider.swift

@@ -19,7 +19,7 @@ public typealias ImageClass = NSImage
 public typealias SimpleCompletionHandler = ((_ error: Error?) -> Void)?
 
 /// This protocol defines FileProvider neccesary functions and properties to connect and get contents list
-public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
+public protocol FileProviderBasic: class, NSSecureCoding {
     /// An string to identify type of provider.
     static var type: String { get }
     
@@ -51,13 +51,13 @@ public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
      
      **Example initialization:**
      ````
-     let credential = URLCredential(user: "user", password: "password", persistence: .forSeession)
+     provider.credential = URLCredential(user: "user", password: "password", persistence: .forSeession)
      ````
      
      - Note: In OAuth based providers like `DropboxFileProvider` and `OneDriveFileProvider`, password is Token.
      use [OAuthSwift](https://github.com/OAuthSwift/OAuthSwift) library to fetch clientId and Token of user.
      */
-    var credential: URLCredential? { get }
+    var credential: URLCredential? { get set }
     
     /**
      Returns an Array of `FileObject`s identifying the the directory entries via asynchronous completion handler.
@@ -66,8 +66,8 @@ public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
      
      - Parameter path: path to target directory. If empty, `currentPath` value will be used.
      - Parameter completionHandler: a closure with result of directory entries or error.
-        `contents`: An array of `FileObject` identifying the the directory entries.
-        `error`: Error returned by system.
+        - `contents`: An array of `FileObject` identifying the the directory entries.
+        - `error`: Error returned by system.
      */
     func contentsOfDirectory(path: String, completionHandler: @escaping ((_ contents: [FileObject], _ error: Error?) -> Void))
     
@@ -78,8 +78,8 @@ public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
      
      - Parameter path: path to target directory. If empty, `currentPath` value will be used.
      - Parameter completionHandler: a closure with result of directory entries or error.
-        `attributes`: A `FileObject` containing the attributes of the item.
-        `error`: Error returned by system.
+        - `attributes`: A `FileObject` containing the attributes of the item.
+        - `error`: Error returned by system.
      */
     func attributesOfItem(path: String, completionHandler: @escaping ((_ attributes: FileObject?, _ error: Error?) -> Void))
     
@@ -99,7 +99,8 @@ public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
        - foundItemHandler: Closure which is called when a file is found
        - completionHandler: Closure which will be called after finishing search. Returns an arry of `FileObject` or error if occured.
      */
-    func searchFiles(path: String, recursive: Bool, query: String, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void))
+    @discardableResult
+    func searchFiles(path: String, recursive: Bool, query: String, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress?
     
     /**
      Search files inside directory using query asynchronously.
@@ -121,8 +122,10 @@ public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
        - query: An `NSPredicate` object with keys like `FileObject` members, except `size` which becomes `filesize`.
        - foundItemHandler: Closure which is called when a file is found
        - completionHandler: Closure which will be called after finishing search. Returns an arry of `FileObject` or error if occured.
+     - Returns: An `Progress` to get progress or cancel progress.
      */
-    func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void))
+    @discardableResult
+    func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress?
     
     /**
      Returns an independent url to access the file. Some providers like `Dropbox` due to their nature.
@@ -132,14 +135,23 @@ public protocol FileProviderBasic: class, NSCoding, NSSecureCoding {
     */
     func url(of path: String?) -> URL
     
+    
+    /// Returns the relative path of url, wothout percent encoding. Even if url is absolute or
+    /// retrieved from another provider, it will try to resolve the url against `baseURL` of
+    /// current provider. It's highly recomended to use this method for displaying purposes.
+    ///
+    /// - Parameter url: Absolute url to file or directory.
+    /// - Returns: A `String` contains relative path of url against base url.
+    func relativePathOf(url: URL) -> String
+    
     /// Checks the connection to server or permission on local
     func isReachable(completionHandler: @escaping(_ success: Bool) -> Void)
 }
 
 extension FileProviderBasic {
-    public func searchFiles(path: String, recursive: Bool, query: String, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) {
+    public func searchFiles(path: String, recursive: Bool, query: String, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
         let predicate = NSPredicate(format: "name BEGINSWITH[c] %@", query)
-        self.searchFiles(path: path, recursive: recursive, query: predicate, foundItemHandler: foundItemHandler, completionHandler: completionHandler)
+        return self.searchFiles(path: path, recursive: recursive, query: predicate, foundItemHandler: foundItemHandler, completionHandler: completionHandler)
     }
     
     /// The maximum number of queued operations that can execute at the same time.
@@ -153,8 +165,6 @@ extension FileProviderBasic {
             operation_queue.maxConcurrentOperationCount = newValue
         }
     }
-    
-    
 }
 
 /// Checking equality of two file provider, regardless of current path queues and delegates.
@@ -195,7 +205,13 @@ public protocol FileProviderBasicRemote: FileProviderBasic {
     var validatingCache: Bool { get set }
 }
 
-internal extension FileProviderBasicRemote {
+internal protocol FileProviderBasicRemoteInternal: FileProviderBasic {
+    var completionHandlersForTasks: [Int: SimpleCompletionHandler] { get set }
+    var downloadCompletionHandlersForTasks: [Int: (URL) -> Void] { get set }
+    var dataCompletionHandlersForTasks: [Int: (Data) -> Void] { get set }
+}
+
+internal extension FileProviderBasicRemote {    
     func returnCachedDate(with request: URLRequest, validatingCache: Bool, completionHandler: @escaping (Data?, URLResponse?, Error?) -> Swift.Void) -> Bool {
         guard let cache = self.cache else { return false }
         if let response = cache.cachedResponse(for: request) {
@@ -226,7 +242,7 @@ internal extension FileProviderBasicRemote {
         return false
     }
     
-    func runDataTask(with request: URLRequest, operationHandle: RemoteOperationHandle? = nil, completionHandler: @escaping (Data?, URLResponse?, Error?) -> Swift.Void) {
+    func runDataTask(with request: URLRequest, operation: FileOperationType? = nil, completionHandler: @escaping (Data?, URLResponse?, Error?) -> Swift.Void) {
         let useCache = self.useCache
         let validatingCache = self.validatingCache
         dispatch_queue.async {
@@ -236,8 +252,7 @@ internal extension FileProviderBasicRemote {
                 }
             }
             let task = self.session.dataTask(with: request, completionHandler: completionHandler)
-            task.taskDescription = operationHandle?.operationType.json
-            operationHandle?.add(task: task)
+            task.taskDescription = operation?.json
             task.resume()
         }
     }
@@ -256,24 +271,10 @@ public protocol FileProviderOperations: FileProviderBasic {
        - folder: Directory name.
        - at: Parent path of new directory.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func create(folder: String, at: String, completionHandler: SimpleCompletionHandler) -> OperationHandle?
-    
-    /**
-     Creates an new file with data passed to method asynchronously. 
-     Returns error via completionHandler if file is already exists.
-     
-     - Parameters:
-       - file: New file name with extension separated by period.
-       - at: Parent path of new file.
-       - data: Data of new files. Pass nil or `Data()` to create empty file.
-       - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
-     */
-    @discardableResult
-    func create(file: String, at: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func create(folder: String, at: String, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Moves a file or directory from `path` to designated path asynchronously.
@@ -284,10 +285,10 @@ public protocol FileProviderOperations: FileProviderBasic {
        - path: original file or directory path.
        - to: destination path of file or directory, including file/directory name.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func moveItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func moveItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Moves a file or directory from `path` to designated path asynchronously.
@@ -299,10 +300,10 @@ public protocol FileProviderOperations: FileProviderBasic {
        - to: destination path of file or directory, including file/directory name.
        - overwrite: Destination file should be overwritten if file is already exists. **Default** is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func moveItem(path: String, to: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func moveItem(path: String, to: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Copies a file or directory from `path` to designated path asynchronously.
@@ -313,10 +314,10 @@ public protocol FileProviderOperations: FileProviderBasic {
        - path: original file or directory path.
        - to: destination path of file or directory, including file/directory name.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func copyItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func copyItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Copies a file or directory from `path` to designated path asynchronously.
@@ -328,10 +329,10 @@ public protocol FileProviderOperations: FileProviderBasic {
        - to: destination path of file or directory, including file/directory name.
        - overwrite: Destination file should be overwritten if file is already exists. **Default** is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func copyItem(path: String, to: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func copyItem(path: String, to: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Removes the file or directory at the specified path.
@@ -339,66 +340,80 @@ public protocol FileProviderOperations: FileProviderBasic {
      - Parameters:
        - path: file or directory path.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      
      */
     @discardableResult
-    func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Uploads a file from local file url to designated path asynchronously.
      Method will fail if source is not a local url with `file://` scheme.
      
+     - Note: It's safe to assume that this method only works on individual files and **won't** copy folders recursively.
+     
      - Parameters:
        - localFile: a file url to file.
        - to: destination path of file, including file/directory name.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress.
+     - Returns: An `Progress` to get progress or cancel progress.
      */
     @discardableResult
-    func copyItem(localFile: URL, to: String, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func copyItem(localFile: URL, to: String, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Uploads a file from local file url to designated path asynchronously.
      Method will fail if source is not a local url with `file://` scheme.
      
+     - Note: It's safe to assume that this method only works on individual files and **won't** copy folders recursively.
+     
      - Parameters:
        - localFile: a file url to file.
        - to: destination path of file, including file/directory name.
        - overwrite: Destination file should be overwritten if file is already exists. **Default** is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress.
+     - Returns: An `Progress` to get progress or cancel progress.
      */
     @discardableResult
-    func copyItem(localFile: URL, to: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func copyItem(localFile: URL, to: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Download a file from `path` to designated local file url asynchronously.
      Method will fail if destination is not a local url with `file://` scheme.
      
+     - Note: It's safe to assume that this method only works on individual files and **won't** copy folders recursively.
+     
      - Parameters:
        - path: original file or directory path.
        - toLocalURL: destination local url of file, including file/directory name.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> Progress?
 }
 
-extension FileProviderOperations {
+public extension FileProviderOperations {
+    /// *DEPRECATED:* Use Use FileProviderReadWrite.writeContents(path:, data:, completionHandler:) method instead.
+    @available(*, deprecated, message: "Use FileProviderReadWrite.writeContents(path:, data:, completionHandler:) method instead.")
     @discardableResult
-    public func moveItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func create(file: String, at: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let path = (at as NSString).appendingPathComponent(file)
+        return (self as? FileProviderReadWrite)?.writeContents(path: path, contents: data, completionHandler: completionHandler)
+    }
+    
+    @discardableResult
+    public func moveItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         return self.moveItem(path: path, to: to, overwrite: false, completionHandler: completionHandler)
     }
     
     @discardableResult
-    public func copyItem(localFile: URL, to: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func copyItem(localFile: URL, to: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         return self.copyItem(localFile: localFile, to: to, overwrite: false, completionHandler: completionHandler)
     }
     
     @discardableResult
-    public func copyItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func copyItem(path: String, to: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         return self.copyItem(path: path, to: to, overwrite: false, completionHandler: completionHandler)
     }
 }
@@ -412,12 +427,12 @@ public protocol FileProviderReadWrite: FileProviderBasic {
      - Parameters:
        - path: Path of file.
        - completionHandler: a closure with result of file contents or error.
-         `contents`: contents of file in a `Data` object.
-         `error`: Error returned by system.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+         - `contents`: contents of file in a `Data` object.
+         - `error`: Error returned by system.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
     */
     @discardableResult
-    func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle?
+    func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress?
     
     /**
      Retreives a `Data` object with a portion contents of the file asynchronously vis contents argument of completion handler.
@@ -428,12 +443,12 @@ public protocol FileProviderReadWrite: FileProviderBasic {
        - offset: First byte index which should be read. **Starts from 0.**
        - length: Bytes count of data. Pass `-1` to read until the end of file.
        - completionHandler: a closure with result of file contents or error.
-         `contents`: contents of file in a `Data` object.
-         `error`: Error returned by system.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+         - `contents`: contents of file in a `Data` object.
+         - `error`: Error returned by system.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle?
+    func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress?
     
     /**
      Write the contents of the `Data` to a location asynchronously.
@@ -442,12 +457,12 @@ public protocol FileProviderReadWrite: FileProviderBasic {
      
      - Parameters:
        - path: Path of target file.
-       - contents: Data to be written into file.
+       - contents: Data to be written into file, pass nil to create empty file.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func writeContents(path: String, contents: Data, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func writeContents(path: String, contents: Data?, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Write the contents of the `Data` to a location asynchronously.
@@ -455,13 +470,13 @@ public protocol FileProviderReadWrite: FileProviderBasic {
      
      - Parameters:
        - path: Path of target file.
-       - contents: Data to be written into file.
+       - contents: Data to be written into file, pass nil to create empty file.
        - atomically: data will be written to a temporary file before writing to final location. Default is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func writeContents(path: String, contents: Data, atomically: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func writeContents(path: String, contents: Data?, atomically: Bool, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Write the contents of the `Data` to a location asynchronously.
@@ -469,47 +484,47 @@ public protocol FileProviderReadWrite: FileProviderBasic {
      
      - Parameters:
      - path: Path of target file.
-       - contents: Data to be written into file.
+       - contents: Data to be written into file, pass nil to create empty file.
        - overwrite: Destination file should be overwritten if file is already exists. Default is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func writeContents(path: String, contents: Data, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func writeContents(path: String, contents: Data?, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress?
     
     /**
      Write the contents of the `Data` to a location asynchronously.
      
      - Parameters:
        - path: Path of target file.
-       - contents: Data to be written into file.
+       - contents: Data to be written into file, pass nil to create empty file.
        - overwrite: Destination file should be overwritten if file is already exists. Default is `false`.
        - atomically: data will be written to a temporary file before writing to final location. Default is `false`.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
-     - Returns: An `OperationHandle` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
+     - Returns: An `Progress` to get progress or cancel progress. Doesn't work on `LocalFileProvider`.
      */
     @discardableResult
-    func writeContents(path: String, contents: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle?
+    func writeContents(path: String, contents: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress?
 }
 
 extension FileProviderReadWrite {
     @discardableResult
-    public func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle?{
+    public func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         return self.contents(path: path, offset: 0, length: -1, completionHandler: completionHandler)
     }
     
     @discardableResult
-    public func writeContents(path: String, contents: Data, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func writeContents(path: String, contents: Data?, completionHandler: SimpleCompletionHandler) -> Progress? {
         return self.writeContents(path: path, contents: contents, atomically: false, overwrite: false, completionHandler: completionHandler)
     }
     
     @discardableResult
-    public func writeContents(path: String, contents: Data, atomically: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func writeContents(path: String, contents: Data?, atomically: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         return self.writeContents(path: path, contents: contents, atomically: atomically, overwrite: false, completionHandler: completionHandler)
     }
     
     @discardableResult
-    public func writeContents(path: String, contents: Data, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    public func writeContents(path: String, contents: Data?, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         return self.writeContents(path: path, contents: contents, atomically: false, overwrite: overwrite, completionHandler: completionHandler)
     }
 }
@@ -555,7 +570,7 @@ public protocol FileProvideUndoable: FileProviderOperations {
     var undoManager: UndoManager? { get set }
     
     /// UndoManager supports undoing this file operation
-    func canUndo(handle: OperationHandle) -> Bool
+    func canUndo(handle: Progress) -> Bool
     /// UndoManager supports undoing this operation
     func canUndo(operation: FileOperationType) -> Bool
 }
@@ -565,8 +580,11 @@ public extension FileProvideUndoable {
         return undoOperation(for: operation) != nil
     }
     
-    public func canUndo(handle: OperationHandle) -> Bool {
-        return canUndo(operation: handle.operationType)
+    public func canUndo(handle: Progress) -> Bool {
+        if let operationType = handle.userInfo[.fileProvderOperationTypeKey] as? FileOperationType {
+            return canUndo(operation: operationType)
+        }
+        return false
     }
     
     internal func undoOperation(for operation: FileOperationType) -> FileOperationType? {
@@ -596,21 +614,39 @@ public extension FileProvideUndoable {
     }
 }
 
+/// This protocol defines method to share a public link with other users
+public protocol FileProviderSharing {
+    /**
+     Genrates a public url to a file to be shared with other users and can be downloaded without authentication.
+     
+     - Important: In some providers url will be available for a limitied time, determined in `expiration` argument.
+         e.g. Dropbox links will be expired after 4 hours.
+     
+     - Parameters:
+         - to: path of file, including file/directory name.
+         - completionHandler: a closure with result of directory entries or error.
+             - `link`: a url returned by Dropbox to share.
+             - `attribute`: a `FileObject` containing the attributes of the item.
+             - `expiration`: a `Date` object, determines when the public url will expires.
+             - `error`: Error returned by server.
+     */
+    func publicLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: FileObject?, _ expiration: Date?, _ error: Error?) -> Void))
+}
+
 /// Defines protocol for provider allows all common operations.
-public protocol FileProvider: FileProviderBasic, FileProviderOperations, FileProviderReadWrite, NSCopying {
+public protocol FileProvider: FileProviderOperations, FileProviderReadWrite, NSCopying {
 }
 
 internal let pathTrimSet = CharacterSet(charactersIn: " /")
 extension FileProviderBasic {
     public var type: String {
+        #if swift(>=3.1)
+        return Swift.type(of: self).type
+        #else
         return type(of: self).type
+        #endif
     }
     
-    /// **OBSOLETED** This property never worked as expected and is redundant as only supported by `LocalFileProvider`.
-    /// To simulate `false` value, assign `URL(fileURLWithPath: "/")` to `baseURL`.
-    @available(*, obsoleted: 1.0, message: "Redundant property, now is always true.")
-    var isPathRelative: Bool { return true }
-    
     public func url(of path: String? = nil) -> URL {
         var rpath: String = path ?? self.currentPath
         rpath = rpath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? rpath
@@ -624,26 +660,29 @@ extension FileProviderBasic {
         }
     }
     
-    
-    /// Returns the relative path of url, wothout percent encoding. Even if url is absolute or
-    /// retrieved from another provider, it will try to resolve the url against `baseURL` of
-    /// current provider. It's highly recomended to use this method for displaying purposes.
-    ///
-    /// - Parameter url: Absolute url to file or directory.
-    /// - Returns: A `String` contains relative path of url against base url.
     public func relativePathOf(url: URL) -> String {
         // check if url derieved from current base url
         let relativePath = url.relativePath
         if !relativePath.isEmpty, url.baseURL == self.baseURL {
-            return relativePath.removingPercentEncoding ?? relativePath
+            return (relativePath.removingPercentEncoding ?? relativePath).replacingOccurrences(of: "/", with: "", options: .anchored)
         }
         
         // resolve url string against baseurl
-        guard let baseURL = self.baseURL?.standardizedFileURL else { return url.absoluteString }
-        let standardPath = url.absoluteString.replacingOccurrences(of: "file:///private/var/", with: "file:///var/", options: .anchored)
-        let standardBase = baseURL.absoluteString.replacingOccurrences(of: "file:///private/var/", with: "file:///var/", options: .anchored)
-        let standardRelativePath = standardPath.replacingOccurrences(of: standardBase, with: "/")
-        return standardRelativePath.removingPercentEncoding ?? standardRelativePath
+        if baseURL?.isFileURL ?? false {
+            guard let baseURL = self.baseURL?.standardizedFileURL else { return url.absoluteString }
+            let standardPath = url.absoluteString.replacingOccurrences(of: "file:///private/var/", with: "file:///var/", options: .anchored)
+            let standardBase = baseURL.absoluteString.replacingOccurrences(of: "file:///private/var/", with: "file:///var/", options: .anchored)
+            let standardRelativePath = standardPath.replacingOccurrences(of: standardBase, with: "/").replacingOccurrences(of: "/", with: "", options: .anchored)
+            return standardRelativePath.removingPercentEncoding ?? standardRelativePath
+        } else {
+            guard let baseURL = self.baseURL else { return url.absoluteString }
+            let standardRelativePath = url.absoluteString.replacingOccurrences(of: baseURL.absoluteString, with: "/").replacingOccurrences(of: "/", with: "", options: .anchored)
+            if URLComponents(string: standardRelativePath)?.host?.isEmpty ?? true {
+                return standardRelativePath.removingPercentEncoding ?? standardRelativePath
+            } else {
+                return relativePath.replacingOccurrences(of: "/", with: "", options: .anchored)
+            }
+        }
     }
     
     internal func correctPath(_ path: String?) -> String? {
@@ -678,7 +717,7 @@ extension FileProviderBasic {
             }
             var i = number ?? 2
             let similiar = contents.map {
-                $0.url?.lastPathComponent ?? $0.name
+                $0.url.lastPathComponent.isEmpty ? $0.name : $0.url.lastPathComponent
             }.filter {
                 $0.hasPrefix(result)
             }
@@ -698,6 +737,8 @@ extension FileProviderBasic {
         let domain: String
         switch code {
         case is URLError:
+            fallthrough
+        case is URLError.Code:
             domain = NSURLErrorDomain
         default:
             domain = NSCocoaErrorDomain
@@ -732,8 +773,8 @@ public protocol ExtendedFileProvider: FileProviderBasic {
      - Parameters:
        - path: path of file.
        - completionHandler: a closure with result of preview image or error.
-         `image`: `NSImage`/`UIImage` object contains preview.
-         `error`: Error returned by system.
+         - `image`: `NSImage`/`UIImage` object contains preview.
+         - `error`: Error returned by system.
     */
     func thumbnailOfFile(path: String, completionHandler: @escaping ((_ image: ImageClass?, _ error: Error?) -> Void))
     
@@ -748,8 +789,8 @@ public protocol ExtendedFileProvider: FileProviderBasic {
        - path: path of file.
        - dimension: width and height of result preview image.
        - completionHandler: a closure with result of preview image or error.
-         `image`: `NSImage`/`UIImage` object contains preview.
-     `error`: Error returned by system.
+         - `image`: `NSImage`/`UIImage` object contains preview.
+         - `error`: Error returned by system.
      */
     func thumbnailOfFile(path: String, dimension: CGSize?, completionHandler: @escaping ((_ image: ImageClass?, _ error: Error?) -> Void))
     
@@ -763,9 +804,9 @@ public protocol ExtendedFileProvider: FileProviderBasic {
      - Parameters:
        - path: path of file.
        - completionHandler: a closure with result of preview image or error.
-         `propertiesDictionary`: A `Dictionary` of proprty keys and values.
-         `keys`: An `Array` contains ordering of keys.
-         `error`: Error returned by system.
+         - `propertiesDictionary`: A `Dictionary` of proprty keys and values.
+         - `keys`: An `Array` contains ordering of keys.
+         - `error`: Error returned by system.
      */
     func propertiesOfFile(path: String, completionHandler: @escaping ((_ propertiesDictionary: [String: Any], _ keys: [String], _ error: Error?) -> Void))
 }
@@ -829,19 +870,20 @@ extension ExtendedFileProvider {
             return resultingImage
         #else
             let ppp = Int(UIScreen.main.scale) // fetch device is retina or not
-            guard let context = UIGraphicsGetCurrentContext() else {
-                return nil
-            }
             size.width  *= CGFloat(ppp)
             size.height *= CGFloat(ppp)
             UIGraphicsBeginImageContext(size)
-            
+            guard let context = UIGraphicsGetCurrentContext() else {
+                return nil
+            }
             context.saveGState()
             let transform = pdfPage.getDrawingTransform(CGPDFBox.mediaBox, rect: rect, rotate: 0, preserveAspectRatio: true)
             context.concatenate(transform)
             
             context.translateBy(x: 0, y: size.height)
             context.scaleBy(x: CGFloat(ppp), y: CGFloat(-ppp))
+            context.setFillColor(UIColor.white.cgColor)
+            context.fill(rect)
             context.drawPDFPage(pdfPage)
             
             context.restoreGState()
@@ -938,6 +980,8 @@ public enum FileOperationType: CustomStringConvertible {
         }
         let dest = json["dest"] as? String
         switch type {
+        case "Fetch":
+            self = .fetch(path: source)
         case "Create":
             self = .create(path: source)
         case "Modify":
@@ -967,6 +1011,7 @@ public enum FileOperationType: CustomStringConvertible {
 }
 
 /// Allows to get progress or cancel an in-progress operation, useful for remote providers
+@available(*, obsoleted: 1.0, message: "Use Progress class class instead.")
 public protocol OperationHandle {
     /// Operation supposed to be done on files. Contains file paths as associated value.
     var operationType: FileOperationType { get }
@@ -987,14 +1032,6 @@ public protocol OperationHandle {
     func cancel() -> Bool
 }
 
-public extension OperationHandle {
-    public var progress: Float {
-        let bytesSoFar = self.bytesSoFar
-        let totalBytes = self.totalBytes
-        return totalBytes > 0 ? Float(Double(bytesSoFar) / Double(totalBytes)) : Float.nan
-    }
-}
-
 /// Delegate methods for reporting provider's operation result and progress, when it's ready to update
 /// user interface.
 /// All methods are called in main thread to avoids UI bugs.
@@ -1021,16 +1058,11 @@ public protocol FileOperationDelegate: class {
     func fileProvider(_ fileProvider: FileProviderOperations, shouldProceedAfterError error: Error, operation: FileOperationType) -> Bool
 }
 
-internal class Weak<T: AnyObject> {
-    weak var value : T?
-    init (_ value: T) {
-        self.value = value
-    }
-}
-
 /// For internal use in `FileProvider` framework
 public protocol FoundationErrorEnum {
+    /// Init from error code
     init? (rawValue: Int)
+    // Raw error code
     var rawValue: Int { get }
 }
 

Sources/FileProviderExtensions.swift

@@ -8,7 +8,7 @@
 
 import Foundation
 
-extension Array where Element: FileObject {
+public extension Array where Element: FileObject {
     /// Returns a sorted array of `FileObject`s by criterias set in attributes.
     public func sort(by type: FileObjectSorting.SortType, ascending: Bool = true, isDirectoriesFirst: Bool = false) -> [Element] {
         let sorting = FileObjectSorting(type: type, ascending: ascending, isDirectoriesFirst: isDirectoriesFirst)
@@ -21,8 +21,8 @@ extension Array where Element: FileObject {
     }
 }
 
-extension URLFileResourceType {
-    /// Returns corresponding `URLFileResourceType` of a `FileAttributeType` value
+public extension URLFileResourceType {
+    /// **FileProvider** returns corresponding `URLFileResourceType` of a `FileAttributeType` value
     public init(fileTypeValue: FileAttributeType) {
         switch fileTypeValue {
         case FileAttributeType.typeCharacterSpecial: self = .characterSpecial
@@ -37,11 +37,22 @@ extension URLFileResourceType {
     }
 }
 
-internal extension URLResourceKey {
-    static let fileURL = URLResourceKey(rawValue: "NSURLFileURLKey")
-    static let serverDate = URLResourceKey(rawValue: "NSURLServerDateKey")
-    static let entryTag = URLResourceKey(rawValue: "NSURLEntryTagKey")
-    static let mimeType = URLResourceKey(rawValue: "NSURLMIMETypeIdentifierKey")
+public extension URLResourceKey {
+    /// **FileProvider** returns url of file object.
+    public static let fileURLKey = URLResourceKey(rawValue: "NSURLFileURLKey")
+    /// **FileProvider** returns modification date of file in server
+    public static let serverDateKey = URLResourceKey(rawValue: "NSURLServerDateKey")
+    /// **FileProvider** returns HTTP ETag string of remote resource
+    public static let entryTagKey = URLResourceKey(rawValue: "NSURLEntryTagKey")
+    /// **FileProvider** returns MIME type of file, if returned by server
+    public static let mimeTypeKey = URLResourceKey(rawValue: "NSURLMIMETypeIdentifierKey")
+    /// **FileProvider** returns either file is encrypted or not
+    public static let isEncryptedKey = URLResourceKey(rawValue: "NSURLIsEncryptedKey")
+}
+
+public extension ProgressUserInfoKey {
+    public static let fileProvderOperationTypeKey = ProgressUserInfoKey("FilesProviderOperationTypeKey")
+    public static let startingTimeKey = ProgressUserInfoKey("NSProgressstartingTimeKey")
 }
 
 internal extension URL {
@@ -62,6 +73,76 @@ internal extension URL {
     }
 }
 
+internal extension URLRequest {
+    mutating func set(httpAuthentication credential: URLCredential?, with type: HTTPAuthenticationType) {
+        func base64(_ str: String) -> String {
+            let plainData = str.data(using: .utf8)
+            let base64String = plainData!.base64EncodedString(options: [])
+            return base64String
+        }
+        
+        guard let credential = credential else { return }
+        switch type {
+        case .basic:
+            let authStr = "\(credential.user ?? ""):\(credential.password ?? "")"
+            self.setValue("Basic \(authStr)", forHTTPHeaderField: "Authorization")
+        case .digest:
+            // handled by RemoteSessionDelegate
+            break
+        case .oAuth1:
+            if let oauth = credential.password {
+                self.setValue("OAuth \(oauth)", forHTTPHeaderField: "Authorization")
+            }
+        case .oAuth2:
+            if let bearer = credential.password {
+                self.setValue("Bearer \(bearer)", forHTTPHeaderField: "Authorization")
+            }
+        }
+    }
+    
+    mutating func set(rangeWithOffset offset: Int64, length: Int) {
+        if length > 0 {
+            self.setValue("bytes=\(offset)-\(offset + Int64(length) - 1)", forHTTPHeaderField: "Range")
+        } else if offset > 0 && length < 0 {
+            self.setValue("bytes=\(offset)-", forHTTPHeaderField: "Range")
+        }
+    }
+    
+    enum ContentType: String {
+        case json = "application/json"
+        case stream = "application/octet-stream"
+        case xml = "text/xml; charset=\"utf-8\""
+    }
+    
+    mutating func set(contentType: ContentType) {
+        self.setValue(contentType.rawValue, forHTTPHeaderField: "Content-Type")
+    }
+    
+    private func asciiEscape(string:String) -> String {
+        var res = ""
+        for char in string.unicodeScalars {
+            let substring = String(char)
+            if substring.canBeConverted(to: .ascii) {
+                res.append(substring)
+            } else {
+                res = res.appendingFormat("\\u%04x", char.value)
+            }
+        }
+        return res
+    }
+    
+    mutating func set(dropboxArgKey requestDictionary: [String: AnyObject]) {
+        guard let jsonData = try? JSONSerialization.data(withJSONObject: requestDictionary, options: []) else {
+            return
+        }
+        guard var jsonString = String(data: jsonData, encoding: .utf8) else { return }
+        jsonString = self.asciiEscape(string: jsonString)
+        jsonString = jsonString.replacingOccurrences(of: "\\/", with: "/")
+        
+        self.setValue(jsonString, forHTTPHeaderField: "Dropbox-API-Arg")
+    }
+}
+
 internal extension Data {
     internal var isPDF: Bool {
         return self.count > 4 && self.scanString(length: 4, using: .ascii) == "%PDF"
@@ -151,7 +232,44 @@ internal extension TimeInterval {
     }
 }
 
-extension NSPredicate {
+internal extension Date {
+   init?(rfcString: String) {
+        let dateFor: DateFormatter = DateFormatter()
+        dateFor.locale = Locale(identifier: "en_US")
+        dateFor.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ssZ"
+        if let rfc3339 = dateFor.date(from: rfcString) {
+            self = rfc3339
+            return
+        }
+        dateFor.dateFormat = "EEE',' dd' 'MMM' 'yyyy HH':'mm':'ss z"
+        if let rfc1123 = dateFor.date(from: rfcString) {
+            self = rfc1123
+             return
+        }
+        dateFor.dateFormat = "EEEE',' dd'-'MMM'-'yy HH':'mm':'ss z"
+        if let rfc850 = dateFor.date(from: rfcString) {
+            self = rfc850
+             return
+        }
+        dateFor.dateFormat = "EEE MMM d HH':'mm':'ss yyyy"
+        if let asctime = dateFor.date(from: rfcString) {
+            self = asctime
+             return
+        }
+        
+        return nil
+    }
+    
+    internal func rfc3339utc() -> String {
+        let fm = DateFormatter()
+        fm.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"
+        fm.timeZone = TimeZone(identifier: "UTC")
+        fm.locale = Locale(identifier: "en_US_POSIX")
+        return fm.string(from: self)
+    }
+}
+
+internal extension NSPredicate {
     func findValue(forKey key: String?, operator op: NSComparisonPredicate.Operator? = nil) -> Any? {
         let val = findAllValues(forKey: key).lazy.filter { (op == nil || $0.operator == op!) && !$0.not }
         return val.first?.value

Sources/LocalFileProvider.swift

@@ -21,7 +21,7 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
     open var dispatch_queue: DispatchQueue
     open var operation_queue: OperationQueue
     open weak var delegate: FileProviderDelegate?
-    open internal(set) var credential: URLCredential?
+    open var credential: URLCredential?
     
     /// Underlying `FileManager` object for listing and metadata fetching.
     open private(set) var fileManager = FileManager()
@@ -70,7 +70,7 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
             return nil
         }
         
-        var finalBaseURL = baseURL
+        var finalBaseURL = baseURL.absoluteURL
         
         switch directory {
         case .documentDirectory:
@@ -98,14 +98,19 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
         guard baseURL.isFileURL else {
             fatalError("Cannot initialize a Local provider from remote URL.")
         }
-        self.baseURL = baseURL
+        self.baseURL = (baseURL.absoluteString.hasSuffix("/") ? baseURL : baseURL.appendingPathComponent("")).absoluteURL
         self.currentPath = ""
         self.credential = nil
         self.isCoorinating = false
         
-        dispatch_queue = DispatchQueue(label: "FileProvider.\(type(of: self).type)", attributes: .concurrent)
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
         operation_queue = OperationQueue()
-        operation_queue.name = "FileProvider.\(type(of: self).type).Operation"
+        operation_queue.name = "\(queueLabel).Operation"
         
         fileProviderManagerDelegate = LocalFileProviderManagerDelegate(provider: self)
         opFileManager.delegate = fileProviderManagerDelegate
@@ -116,7 +121,7 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
             return nil
         }
         self.init(baseURL: baseURL)
-        self.currentPath   = aDecoder.decodeObject(of: NSString.self, forKey: "currentPath") as? String ?? ""
+        self.currentPath   = aDecoder.decodeObject(forKey: "currentPath") as? String ?? ""
         self.isCoorinating = aDecoder.decodeBool(forKey: "isCoorinating")
     }
     
@@ -140,12 +145,6 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
         return copy
     }
     
-    /// **OBSOLETED:** No longer is in use and overriding this method has no effect anymore.
-    @available(*, obsoleted: 1.0, message: "Overriding this method has no effect anymore.")
-    open class func defaultBaseURL() -> URL {
-        return FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
-    }
-    
     open func contentsOfDirectory(path: String, completionHandler: @escaping ((_ contents: [FileObject], _ error: Error?) -> Void)) {
         dispatch_queue.async {
             do {
@@ -174,22 +173,31 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
         completionHandler(totalSize, totalSize - freeSize)
     }
     
-    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) {
+    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
+        let progress = Progress(parent: nil, userInfo: nil)
+        
         dispatch_queue.async {
+            progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
             let iterator = self.fileManager.enumerator(at: self.url(of: path), includingPropertiesForKeys: nil, options: recursive ? [] : [.skipsSubdirectoryDescendants, .skipsPackageDescendants]) { (url, e) -> Bool in
                 completionHandler([], e)
                 return true
             }
             var result = [LocalFileObject]()
             while let fileURL = iterator?.nextObject() as? URL {
+                if progress.isCancelled {
+                    break
+                }
                 let path = self.relativePathOf(url: fileURL)
                 if let fileObject = LocalFileObject(fileWithPath: path, relativeTo: self.baseURL), query.evaluate(with: fileObject.mapPredicate()) {
                     result.append(fileObject)
+                    progress.completedUnitCount = Int64(result.count)
                     foundItemHandler?(fileObject)
                 }
             }
             completionHandler(result, nil)
         }
+        
+        return progress
     }
     
     open func isReachable(completionHandler: @escaping (Bool) -> Void) {
@@ -201,22 +209,13 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
     open weak var fileOperationDelegate : FileOperationDelegate?
     
     @discardableResult
-    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.create(path: (atPath as NSString).appendingPathComponent(folderName) + "/")
         return self.doOperation(opType, completionHandler: completionHandler)
     }
     
     @discardableResult
-    open func create(file fileName: String, at atPath: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let fileName = fileName.trimmingCharacters(in: CharacterSet(charactersIn: "/"))
-        let path = (atPath as NSString).appendingPathComponent(fileName)
-        let opType = FileOperationType.create(path: path)
-        
-        return self.doOperation(opType, data: data, atomically: true, completionHandler: completionHandler)
-    }
-    
-    @discardableResult
-    open func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.move(source: path, destination: toPath)
 
         if !overwrite && self.fileManager.fileExists(atPath: self.url(of: toPath).path) {
@@ -228,7 +227,7 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
     }
     
     @discardableResult
-    open func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.copy(source: path, destination: toPath)
         
         if !overwrite && self.fileManager.fileExists(atPath: self.url(of: toPath).path) {
@@ -242,13 +241,13 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
     }
     
     @discardableResult
-    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.remove(path: path)
         return self.doOperation(opType, completionHandler: completionHandler)
     }
     
     @discardableResult
-    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         if !overwrite && self.fileManager.fileExists(atPath: self.url(of: toPath).path) {
             self.dispatch_queue.async {
                 completionHandler?(self.throwError(toPath, code: CocoaError.fileWriteFileExists as FoundationErrorEnum))
@@ -260,12 +259,12 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
     }
     
     @discardableResult
-    open func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.copy(source: path, destination: toLocalURL.absoluteString)
         return self.doOperation(opType, completionHandler: completionHandler)
     }
     
-    dynamic func doSimpleOperation(_ box: UndoBox) {
+    @objc dynamic func doSimpleOperation(_ box: UndoBox) {
         guard let _ = self.undoManager else { return }
         _ = self.doOperation(box.undoOperation) { (_) in
             return
@@ -273,8 +272,12 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
     }
     
     @discardableResult
-    fileprivate func doOperation(_ opType: FileOperationType, data: Data? = nil, atomically: Bool = false, forUploading: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        
+    fileprivate func doOperation(_ opType: FileOperationType, data: Data? = nil, atomically: Bool = false, forUploading: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.isCancellable = false
+        progress.setUserInfoObject(Progress.FileOperationKind.receiving, forKey: .fileOperationKindKey)
         func urlofpath(path: String) -> URL {
             if path.hasPrefix("file://") {
                 let removedSchemePath = path.replacingOccurrences(of: "file://", with: "", options: .anchored)
@@ -308,22 +311,31 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
         
         let operationHandler: (URL, URL?) -> Void = { source, dest in
             do {
+                progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
                 switch opType {
                 case .create:
                     if sourcePath.hasSuffix("/") {
+                        progress.totalUnitCount = 1
                         try self.opFileManager.createDirectory(at: source, withIntermediateDirectories: true, attributes: [:])
                     } else {
+                        progress.totalUnitCount = Int64(data?.count ?? 0)
                         try data?.write(to: source, options: .atomic)
                     }
                 case .modify:
+                    progress.totalUnitCount = Int64(data?.count ?? 0)
                     try data?.write(to: source, options: atomically ? [.atomic] : [])
                 case .copy:
                     guard let dest = dest else { return }
+                    progress.setUserInfoObject(Progress.FileOperationKind.copying, forKey: .fileOperationKindKey)
+                    progress.totalUnitCount = abs(source.fileSize)
                     try self.opFileManager.copyItem(at: source, to: dest)
                 case .move:
+                    progress.setUserInfoObject(Progress.FileOperationKind.copying, forKey: .fileOperationKindKey)
                     guard let dest = dest else { return }
+                    progress.totalUnitCount = abs(source.fileSize)
                     try self.opFileManager.moveItem(at: source, to: dest)
                 case.remove:
+                    progress.totalUnitCount = abs(source.fileSize)
                     try self.opFileManager.removeItem(at: source)
                 default:
                     return
@@ -331,7 +343,8 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
                 if successfulSecurityScopedResourceAccess {
                     source.stopAccessingSecurityScopedResource()
                 }
-                
+
+                progress.completedUnitCount = progress.totalUnitCount
                 self.dispatch_queue.async {
                     completionHandler?(nil)
                 }
@@ -342,6 +355,7 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
                 if successfulSecurityScopedResourceAccess {
                     source.stopAccessingSecurityScopedResource()
                 }
+                progress.cancel()
                 self.dispatch_queue.async {
                     completionHandler?(e)
                 }
@@ -383,22 +397,31 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
                 operationHandler(source, dest)
             }
         }
-        
-        return LocalOperationHandle(operationType: opType, baseURL: self.baseURL)
+        return progress
     }
     
     @discardableResult
-    open func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         let opType = FileOperationType.fetch(path: path)
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.isCancellable = false
+        progress.setUserInfoObject(Progress.FileOperationKind.receiving, forKey: .fileOperationKindKey)
+        
         let url = self.url(of: path)
+        progress.totalUnitCount = url.fileSize
         
         let operationHandler: (URL) -> Void = { url in
+            progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
             do {
                 let data = try Data(contentsOf: url)
+                progress.completedUnitCount = progress.totalUnitCount
                 self.dispatch_queue.async {
                     completionHandler(data, nil)
                 }
             } catch let e {
+                progress.cancel()
                 self.dispatch_queue.async {
                     completionHandler(nil, e)
                 }
@@ -420,24 +443,30 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
                 operationHandler(url)
             }
         }
-        
-        return LocalOperationHandle(operationType: opType, baseURL: self.baseURL)
+
+        return progress
     }
     
     @discardableResult
-    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         if length == 0 || offset < 0 {
             dispatch_queue.async {
                 completionHandler(Data(), nil)
             }
             return nil
         }
-        
+
         if offset == 0 && length < 0 {
             return self.contents(path: path, completionHandler: completionHandler)
         }
-        
+
         let opType = FileOperationType.fetch(path: path)
+        let progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.isCancellable = false
+        progress.setUserInfoObject(Progress.FileOperationKind.receiving, forKey: .fileOperationKindKey)
+        
         let url = self.url(of: path)
         
         let operationHandler: (URL) -> Void = { url in
@@ -451,16 +480,20 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
             defer {
                 handle.closeFile()
             }
-            
+
             let size = LocalFileObject(fileWithURL: url)?.size ?? -1
+            progress.totalUnitCount = size
             guard size > offset else {
+                progress.cancel()
                 self.dispatch_queue.async {
                     completionHandler(nil, self.throwError(path, code: CocoaError.fileReadTooLarge as FoundationErrorEnum))
                 }
                 return
             }
+            progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
             handle.seek(toFileOffset: UInt64(offset))
             guard Int64(handle.offsetInFile) == offset else {
+                progress.cancel()
                 self.dispatch_queue.async {
                     completionHandler(nil, self.throwError(path, code: CocoaError.fileReadTooLarge as FoundationErrorEnum))
                 }
@@ -468,7 +501,7 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
             }
             
             let data = handle.readData(ofLength: length)
-            
+            progress.completedUnitCount = progress.totalUnitCount
             self.dispatch_queue.async {
                 completionHandler(data, nil)
             }
@@ -488,13 +521,14 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
             }
         }
         
-        return LocalOperationHandle(operationType: opType, baseURL: self.baseURL)
+        return progress
     }
     
     @discardableResult
-    open func writeContents(path: String, contents data: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let opType = FileOperationType.modify(path: path)
-        return self.doOperation(opType, data: data, atomically: atomically, completionHandler: completionHandler)
+    open func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let fileExists = fileManager.fileExists(atPath: url(of: path).path)
+        let opType: FileOperationType = fileExists ? .modify(path: path) : .create(path: path)
+        return self.doOperation(opType, data: data ?? Data(), atomically: atomically, completionHandler: completionHandler)
     }
     
     fileprivate var monitors = [LocalFolderMonitor]()
@@ -532,13 +566,13 @@ open class LocalFileProvider: FileProvider, FileProviderMonitor, FileProvideUndo
 public extension LocalFileProvider {
     /**
      Creates a symbolic link at the specified path that points to an item at the given path.
-     This method does not traverse symbolic links contained in destURL, making it possible 
-     to create symbolic links to locations that do not yet exist. 
-     Also, if the final path component in url is a symbolic link, that link is not followed.
+     This method does not traverse symbolic links contained in destination path, making it possible
+     to create symbolic links to locations that do not yet exist.
+     Also, if the final path component is a symbolic link, that link is not followed.
     
      - Parameters:
-       - path: The file path at which to create the new symbolic link. The last component of the path issued as the name of the link.
-       - destPath: The path that contains the item to be pointed to by the link. In other words, this is the destination of the link.
+       - symbolicLink: The file path at which to create the new symbolic link. The last component of the path issued as the name of the link.
+       - withDestinationPath: The path that contains the item to be pointed to by the link. In other words, this is the destination of the link.
        - completionHandler: If an error parameter was provided, a presentable `Error` will be returned.
     */
     public func create(symbolicLink path: String, withDestinationPath destPath: String, completionHandler: SimpleCompletionHandler) {

Sources/LocalHelper.swift

@@ -10,7 +10,7 @@ import Foundation
 
 /// Containts path, url and attributes of a local file or resource.
 public final class LocalFileObject: FileObject {
-    internal override init(url: URL, name: String, path: String) {
+    internal override init(url: URL?, name: String, path: String) {
         super.init(url: url, name: name, path: path)
     }
     
@@ -19,12 +19,13 @@ public final class LocalFileObject: FileObject {
         var fileURL: URL?
         var rpath = path.replacingOccurrences(of: relativeURL?.path ?? "", with: "", options: .anchored)
         if relativeURL != nil && rpath.hasPrefix("/") {
-            rpath.remove(at: rpath.startIndex)
+            _=rpath.characters.removeFirst()
         }
         if #available(iOS 9.0, macOS 10.11, tvOS 9.0, *) {
             fileURL = URL(fileURLWithPath: rpath, relativeTo: relativeURL)
         } else {
-            fileURL = URL(string: rpath.isEmpty ? "./" : rpath, relativeTo: relativeURL)
+            rpath = rpath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? rpath
+            fileURL = URL(string: rpath, relativeTo: relativeURL) ?? relativeURL
         }
         
         if let fileURL = fileURL {
@@ -37,7 +38,7 @@ public final class LocalFileObject: FileObject {
     /// Initiates a `LocalFileObject` with attributes of file in url.
     public convenience init?(fileWithURL fileURL: URL) {
         do {
-            let values = try fileURL.resourceValues(forKeys: [.nameKey, .fileSizeKey, .fileAllocatedSizeKey, .creationDateKey, .contentModificationDateKey, .fileResourceTypeKey, .isHiddenKey, .isWritableKey, .typeIdentifierKey, .generationIdentifierKey, .documentIdentifierKey])
+            let values = try fileURL.resourceValues(forKeys: [.nameKey, .fileSizeKey, .totalFileSizeKey, .fileAllocatedSizeKey, .totalFileAllocatedSizeKey, .creationDateKey, .contentModificationDateKey, .fileResourceTypeKey, .isHiddenKey, .isWritableKey, .typeIdentifierKey, .generationIdentifierKey, .documentIdentifierKey])
             let path = fileURL.relativePath.hasPrefix("/") ? fileURL.relativePath : "/" + fileURL.relativePath
             
             self.init(url: fileURL, name: values.name ?? fileURL.lastPathComponent, path: path)
@@ -216,102 +217,6 @@ internal class LocalFileProviderManagerDelegate: NSObject, FileManagerDelegate {
     }
 }
 
-/// Local operation handling is limited. Please don't use as much as possible.
-open class LocalOperationHandle: OperationHandle {
-    public let baseURL: URL
-    public let operationType: FileOperationType
-    
-    init (operationType: FileOperationType, baseURL: URL?) {
-        self.baseURL = baseURL ?? URL(fileURLWithPath: "/")
-        self.operationType = operationType
-    }
-    
-    private var sourceURL: URL? {
-        guard let source = operationType.source else { return nil }
-        return source.hasPrefix("file://") ? URL(fileURLWithPath: source) : baseURL.appendingPathComponent(source)
-    }
-    
-    private var destURL: URL? {
-        guard let dest = operationType.destination else { return nil }
-        return dest.hasPrefix("file://") ? URL(fileURLWithPath: dest) : baseURL.appendingPathComponent(dest)
-    }
-    
-    /// Caution: may put pressure on CPU, may have latency
-    open var bytesSoFar: Int64 {
-        assert(!Thread.isMainThread, "Don't run \(#function) method on main thread")
-        switch operationType {
-        case .modify:
-            guard let url = sourceURL, url.isFileURL else { return 0 }
-            if url.fileIsDirectory {
-                return iterateDirectory(url, deep: true).totalsize
-            } else {
-                return url.fileSize
-            }
-        case .copy, .move:
-            guard let url = destURL, url.isFileURL else { return 0 }
-            if url.fileIsDirectory {
-                return iterateDirectory(url, deep: true).totalsize
-            } else {
-                return url.fileSize
-            }
-        default:
-            return 0
-        }
-        
-    }
-    
-    /// Caution: may put pressure on CPU, may have latency
-    open var totalBytes: Int64 {
-        assert(!Thread.isMainThread, "Don't run \(#function) method on main thread")
-        switch operationType {
-        case .copy, .move:
-            guard let url = sourceURL, url.isFileURL else { return 0 }
-            if url.fileIsDirectory {
-                return iterateDirectory(url, deep: true).totalsize
-            } else {
-                return url.fileSize
-            }
-        default:
-            return 0
-        }
-    }
-    
-    /// Not usable in local provider
-    open var inProgress: Bool {
-        return false
-    }
-    
-    /// Not usable in local provider
-    open func cancel() -> Bool{
-        return false
-    }
-    
-    func iterateDirectory(_ pathURL: URL, deep: Bool) -> (folders: Int, files: Int, totalsize: Int64) {
-        var folders = 0
-        var files = 0
-        var totalsize: Int64 = 0
-        let keys: [URLResourceKey] = [.isDirectoryKey, .fileSizeKey]
-        let enumOpt: FileManager.DirectoryEnumerationOptions = !deep ? [.skipsSubdirectoryDescendants, .skipsPackageDescendants] : []
-        
-        let fp = FileManager()
-        let filesList = fp.enumerator(at: pathURL, includingPropertiesForKeys: keys, options: enumOpt, errorHandler: nil)
-        while let fileURL = filesList?.nextObject() as? URL {
-            guard let values = try? fileURL.resourceValues(forKeys: [.isDirectoryKey, .fileSizeKey]) else { continue }
-            let isdir = values.isDirectory ?? false
-            let size = Int64(values.fileSize ?? 0)
-            if isdir {
-                folders += 1
-            } else {
-                files += 1
-            }
-            totalsize += size
-        }
-        
-        return (folders, files, totalsize)
-        
-    }
-}
-
 class UndoBox: NSObject {
     weak var provider: FileProvideUndoable?
     let operation: FileOperationType

Sources/OneDriveFileProvider.swift

@@ -33,24 +33,42 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
     }
     
     open weak var delegate: FileProviderDelegate?
-    open let credential: URLCredential?
+    open var credential: URLCredential? {
+        didSet {
+            sessionDelegate?.credential = self.credential
+        }
+    }
     open private(set) var cache: URLCache?
     public var useCache: Bool
     public var validatingCache: Bool
    
     fileprivate var _session: URLSession?
-    fileprivate var sessionDelegate: SessionDelegate?
+    internal fileprivate(set) var sessionDelegate: SessionDelegate?
     public var session: URLSession {
-        if _session == nil {
-            self.sessionDelegate = SessionDelegate(fileProvider: self, credential: credential)
-            let queue = OperationQueue()
-            //queue.underlyingQueue = dispatch_queue
-            let config = URLSessionConfiguration.default
-            config.urlCache = cache
-            config.requestCachePolicy = .returnCacheDataElseLoad
-            _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDelegate?, delegateQueue: queue)
+        get {
+            if _session == nil {
+                self.sessionDelegate = SessionDelegate(fileProvider: self)
+                let queue = OperationQueue()
+                //queue.underlyingQueue = dispatch_queue
+                let config = URLSessionConfiguration.default
+                config.urlCache = cache
+                config.requestCachePolicy = .returnCacheDataElseLoad
+                _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDelegate?, delegateQueue: queue)
+                _session?.sessionDescription = UUID().uuidString
+                initEmptySessionHandler(_session!.sessionDescription!)
+            }
+            return _session!
+        }
+        
+        set {
+            assert(newValue.delegate is SessionDelegate, "session instances should have a SessionDelegate instance as delegate.")
+            _session = newValue
+            if session.sessionDescription?.isEmpty ?? true {
+                _session?.sessionDescription = UUID().uuidString
+            }
+            self.sessionDelegate = newValue.delegate as? SessionDelegate
+            initEmptySessionHandler(_session!.sessionDescription!)
         }
-        return _session!
     }
     
     /**
@@ -68,17 +86,23 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
        - cache: A URLCache to cache downloaded files and contents.
      */
     public init(credential: URLCredential?, serverURL: URL? = nil, drive: String = "root", cache: URLCache? = nil) {
-        let baseURL = serverURL ?? URL(string: "https://api.onedrive.com/")!
-        self.baseURL = baseURL.path.hasSuffix("/") ? baseURL : baseURL.appendingPathComponent("")
+        let baseURL = serverURL?.absoluteURL ?? URL(string: "https://api.onedrive.com/")!
+        self.baseURL = baseURL.absoluteString.hasSuffix("/") ? baseURL : baseURL.appendingPathComponent("")
         self.drive = drive
         self.currentPath = ""
         self.useCache = false
         self.validatingCache = true
         self.cache = cache
         self.credential = credential
-        dispatch_queue = DispatchQueue(label: "FileProvider.\(type(of: self).type)", attributes: .concurrent)
+        
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
         operation_queue = OperationQueue()
-        operation_queue.name = "FileProvider.\(type(of: self).type).Operation"
+        operation_queue.name = "\(queueLabel).Operation"
     }
     
     public required convenience init?(coder aDecoder: NSCoder) {
@@ -114,6 +138,10 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
     }
     
     deinit {
+        if let sessionuuid = _session?.sessionDescription {
+            removeSessionHandler(for: sessionuuid)
+        }
+        
         if fileProviderCancelTasksOnInvalidating {
             _session?.invalidateAndCancel()
         } else {
@@ -130,7 +158,7 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
     open func attributesOfItem(path: String, completionHandler: @escaping ((_ attributes: FileObject?, _ error: Error?) -> Void)) {
         var request = URLRequest(url: url(of: path))
         request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             var serverError: FileProviderOneDriveError?
             var fileObject: OneDriveFileObject?
@@ -149,7 +177,7 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
     open func storageProperties(completionHandler: @escaping ((_ total: Int64, _ used: Int64) -> Void)) {
         var request = URLRequest(url: url())
         request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             var totalSize: Int64 = -1
             var usedSize: Int64 = 0
@@ -162,12 +190,13 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
         task.resume()
     }
     
-    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) {
+    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
         var foundFiles = [OneDriveFileObject]()
         var queryStr: String?
         queryStr = query.findValue(forKey: "name") as? String ?? query.findAllValues(forKey: nil).flatMap { $0.value as? String }.first
-        guard let finalQueryStr = queryStr else { return }
-        search(path, query: finalQueryStr, foundItem: { (file) in
+        guard let finalQueryStr = queryStr else { return nil }
+        let progress = Progress(parent: nil, userInfo: nil)
+        search(path, query: finalQueryStr, progress: progress, foundItem: { (file) in
             if query.evaluate(with: file.mapPredicate()) {
                 foundFiles.append(file)
                 foundItemHandler?(file)
@@ -175,6 +204,7 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
         }, completionHandler: { (error) in
             completionHandler(foundFiles, error)
         })
+        return progress
     }
     
     open func url(of path: String? = nil, modifier: String? = nil) -> URL {
@@ -185,28 +215,30 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
             rpath = self.currentPath
         }
         
+        let driveURL = baseURL!.appendingPathComponent("drive/\(drive):/")
+        
         if rpath.hasPrefix("/") {
-            rpath.remove(at: rpath.startIndex)
+            _=rpath.characters.removeFirst()
         }
         if rpath.isEmpty {
             if let modifier = modifier {
-                return baseURL!.appendingPathComponent("drive/\(drive)/\(modifier)")
+                return driveURL.appendingPathComponent(modifier)
             }
-            return baseURL!.appendingPathComponent("drive/\(drive)")
+            return driveURL
         }
-        let driveURL = baseURL!.appendingPathComponent("drive/\(drive):/")
-        rpath = (rpath.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) ?? rpath)
+        
         rpath = rpath.trimmingCharacters(in: pathTrimSet)
         if let modifier = modifier {
             rpath = rpath + ":/" + modifier
         }
-        return URL(string: rpath, relativeTo: driveURL) ?? driveURL
+        
+        return  driveURL.appendingPathComponent(rpath)
     }
     
     open func isReachable(completionHandler: @escaping (Bool) -> Void) {
         var request = URLRequest(url: url())
         request.httpMethod = "HEAD"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             let status = (response as? HTTPURLResponse)?.statusCode ?? 400
             completionHandler(status == 200)
@@ -219,33 +251,33 @@ open class OneDriveFileProvider: FileProviderBasicRemote {
 
 extension OneDriveFileProvider: FileProviderOperations {
     
-    
-    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         let path = (atPath as NSString).appendingPathComponent(folderName) + "/"
         return doOperation(.create(path: path), completionHandler: completionHandler)
     }
     
-    open func create(file fileName: String, at path: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let filePath = (path as NSString).appendingPathComponent(fileName)
-        return self.writeContents(path: filePath, contents: data ?? Data(), completionHandler: completionHandler)
-    }
-    
-    open func moveItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func moveItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         return doOperation(.move(source: path, destination: toPath), completionHandler: completionHandler)
     }
     
-    open func copyItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         return doOperation(.copy(source: path, destination: toPath), completionHandler: completionHandler)
     }
     
-    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         return doOperation(.remove(path: path), completionHandler: completionHandler)
     }
     
-    fileprivate func doOperation(_ operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    fileprivate func doOperation(_ operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> Progress? {
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: operation) ?? true == true else {
             return nil
         }
+        
+        let progress = Progress(totalUnitCount: 1)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         guard let sourcePath = operation.source else { return nil }
         let destPath = operation.destination
         var request = URLRequest(url: url(of: sourcePath))
@@ -262,10 +294,10 @@ extension OneDriveFileProvider: FileProviderOperations {
             return nil
         }
         
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         var requestDictionary = [String: AnyObject]()
         if let dest = correctPath(destPath) as NSString? {
-            request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+            request.set(contentType: .json)
             requestDictionary["parentReference"] = ("/drive/\(drive):" + dest.deletingLastPathComponent) as NSString
             requestDictionary["name"] = dest.lastPathComponent as NSString
             request.httpBody = Data(jsonDictionary: requestDictionary)
@@ -275,15 +307,32 @@ extension OneDriveFileProvider: FileProviderOperations {
             if let response = response as? HTTPURLResponse, response.statusCode >= 300, let code = FileProviderHTTPErrorCode(rawValue: response.statusCode) {
                  serverError = FileProviderOneDriveError(code: code, path: sourcePath, errorDescription: String(data: data ?? Data(), encoding: .utf8))
             }
+            if serverError == nil && error == nil {
+                progress.completedUnitCount = 1
+            } else {
+                progress.cancel()
+            }
             completionHandler?(serverError ?? error)
             self.delegateNotify(operation, error: serverError ?? error)
         })
         task.taskDescription = operation.json
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: operation, tasks: [task])
+        return progress
     }
     
-    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        // check file is not a folder
+        guard (try? localFile.resourceValues(forKeys: [.fileResourceTypeKey]))?.fileResourceType ?? .unknown == .regular else {
+            dispatch_queue.async {
+                completionHandler?(self.throwError(localFile.path, code: URLError.fileIsDirectory))
+            }
+            return nil
+        }
+        
         let opType = FileOperationType.copy(source: localFile.absoluteString, destination: toPath)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
@@ -291,37 +340,58 @@ extension OneDriveFileProvider: FileProviderOperations {
         return upload_simple(toPath, localFile: localFile, overwrite: overwrite, operation: opType, completionHandler: completionHandler)
     }
     
-    open func copyItem(path: String, toLocalURL destURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, toLocalURL destURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.copy(source: path, destination: destURL.absoluteString)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         var request = URLRequest(url: self.url(of: path, modifier: "content"))
-        request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        let task = session.downloadTask(with: request, completionHandler: { (cacheURL, response, error) in
-            guard let cacheURL = cacheURL, let httpResponse = response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
-                let code = FileProviderHTTPErrorCode(rawValue: (response as? HTTPURLResponse)?.statusCode ?? -1)
-                let errorData : Data? = nil //Data(contentsOf:cacheURL) // TODO: Figure out how to get error response data for the error description
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        let task = session.downloadTask(with: request)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+            if error != nil {
+                progress.cancel()
+            }
+            completionHandler?(error)
+        }
+        downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { tempURL in
+            guard let httpResponse = task.response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
+                let code = FileProviderHTTPErrorCode(rawValue: (task.response as? HTTPURLResponse)?.statusCode ?? -1)
+                let errorData : Data? = nil //Data(contentsOf: cacheURL) // TODO: Figure out how to get error response data for the error description
                 let serverError : FileProviderOneDriveError? = code != nil ? FileProviderOneDriveError(code: code!, path: path, errorDescription: String(data: errorData ?? Data(), encoding: .utf8)) : nil
-                completionHandler?(serverError ?? error)
+                if serverError != nil {
+                    progress.cancel()
+                }
+                completionHandler?(serverError)
                 return
             }
             do {
-                try FileManager.default.moveItem(at: cacheURL, to: destURL)
+                try FileManager.default.moveItem(at: tempURL, to: destURL)
                 completionHandler?(nil)
             } catch let e {
                 completionHandler?(e)
             }
-        })
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
 }
 
 extension OneDriveFileProvider: FileProviderReadWrite {
-    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         if length == 0 || offset < 0 {
             dispatch_queue.async {
                 completionHandler(Data(), nil)
@@ -330,34 +400,59 @@ extension OneDriveFileProvider: FileProviderReadWrite {
         }
         
         let opType = FileOperationType.fetch(path: path)
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         var request = URLRequest(url: self.url(of: path, modifier: "content"))
         request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        if length > 0 {
-            request.setValue("bytes=\(offset)-\(offset + length - 1)", forHTTPHeaderField: "Range")
-        } else if offset > 0 && length < 0 {
-            request.setValue("bytes=\(offset)-", forHTTPHeaderField: "Range")
-        }
-        let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
-            var serverError: FileProviderOneDriveError?
-            if let httpResponse = response as? HTTPURLResponse , httpResponse.statusCode >= 300, let code = FileProviderHTTPErrorCode(rawValue: httpResponse.statusCode) {
-                serverError = FileProviderOneDriveError(code: code, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8))
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(rangeWithOffset: offset, length: length)
+        let task = session.downloadTask(with: request)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+            if error != nil {
+                progress.cancel()
             }
-            let filedata = serverError ?? error == nil ? data : nil
-            completionHandler(filedata, serverError ?? error)
-        })
+            completionHandler(nil, error)
+        }
+        downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { tempURL in            
+            guard let httpResponse = task.response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
+                let code = FileProviderHTTPErrorCode(rawValue: (task.response as? HTTPURLResponse)?.statusCode ?? -1)
+                let errorData : Data? = nil //Data(contentsOf: cacheURL) // TODO: Figure out how to get error response data for the error description
+                let serverError : FileProviderOneDriveError? = code != nil ? FileProviderOneDriveError(code: code!, path: path, errorDescription: String(data: errorData ?? Data(), encoding: .utf8)) : nil
+                if serverError != nil {
+                    progress.cancel()
+                }
+                completionHandler(nil, serverError)
+                return
+            }
+            do {
+                let data = try Data(contentsOf: tempURL)
+                completionHandler(data, nil)
+            } catch let e {
+                completionHandler(nil, e)
+            }
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
     
-    open func writeContents(path: String, contents data: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.modify(path: path)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
         // FIXME: remove 150MB restriction
-        return upload_simple(path, data: data, overwrite: overwrite, operation: opType, completionHandler: completionHandler)
+        return upload_simple(path, data: data ?? Data(), overwrite: overwrite, operation: opType, completionHandler: completionHandler)
     }
     
     fileprivate func registerNotifcation(path: String, eventHandler: (() -> Void)) {
@@ -372,19 +467,10 @@ extension OneDriveFileProvider: FileProviderReadWrite {
     fileprivate func unregisterNotifcation(path: String) {
         NotImplemented()
     }
-    
-    /**
-     Genrates a public url to a file to be shared with other users and can be downloaded without authentication.
-     
-     - Parameters:
-       - to: path of file, including file/directory name.
-       - completionHandler: a closure with result of directory entries or error.
-         `link`: a url returned by OneDrive to share.
-         `attribute`: `nil` for OneDrive.
-         `expiration`: `nil` for OneDrive, as it doesn't expires.
-         `error`: Error returned by OneDrive.
-     */
-    open func publicLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: OneDriveFileObject?, _ expiration: Date?, _ error: Error?) -> Void)) {
+}
+
+extension OneDriveFileProvider: FileProviderSharing {
+    open func publicLink(to path: String, completionHandler: @escaping ((_ link: URL?, _ attribute: FileObject?, _ expiration: Date?, _ error: Error?) -> Void)) {
         var request = URLRequest(url: self.url(of: path, modifier: "action.createLink"))
         request.httpMethod = "POST"
         let requestDictionary: [String: AnyObject] = ["type": "view" as NSString]
@@ -437,7 +523,7 @@ extension OneDriveFileProvider: ExtendedFileProvider {
         }
         
         var request = URLRequest(url: url)
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = self.session.dataTask(with: request, completionHandler: { (data, response, error) in
             var image: ImageClass? = nil
             if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
@@ -456,7 +542,7 @@ extension OneDriveFileProvider: ExtendedFileProvider {
     open func propertiesOfFile(path: String, completionHandler: @escaping ((_ propertiesDictionary: [String : Any], _ keys: [String], _ error: Error?) -> Void)) {
         var request = URLRequest(url: url(of: path))
         request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             var serverError: FileProviderOneDriveError?
             var dic = [String: Any]()

Sources/OneDriveHelper.swift

@@ -18,12 +18,13 @@ public struct FileProviderOneDriveError: FileProviderHTTPError {
 /// Containts path, url and attributes of a OneDrive file or resource.
 public final class OneDriveFileObject: FileObject {
     internal init(baseURL: URL?, name: String, path: String) {
-        var rpath = path
-        if path.hasPrefix("/") {
-            rpath.remove(at: rpath.startIndex)
+        var rpath = (URL(string:path)?.appendingPathComponent(name).absoluteString)!
+        if rpath.hasPrefix("/") {
+            _=rpath.characters.removeFirst()
         }
-        let url = URL(string: rpath, relativeTo: baseURL) ?? URL(string: path)!
-        super.init(url: url, name: name, path: path)
+        let url = URL(string: rpath, relativeTo: baseURL) ?? URL(string: rpath)!
+        
+        super.init(url: url, name: name, path: rpath.removingPercentEncoding ?? path)
     }
     
     internal convenience init? (baseURL: URL?, drive: String, jsonStr: String) {
@@ -34,14 +35,14 @@ public final class OneDriveFileObject: FileObject {
     internal convenience init? (baseURL: URL?, drive: String, json: [String: AnyObject]) {
         guard let name = json["name"] as? String else { return nil }
         guard let path = (json["parentReference"] as? NSDictionary)?["path"] as? String else { return nil }
-        var lPath = path.replacingOccurrences(of: "/drive/\(drive)", with: "/", options: .anchored, range: nil)
+        var lPath = path.replacingOccurrences(of: "/drive/\(drive):", with: "/", options: .anchored, range: nil)
         lPath = lPath.replacingOccurrences(of: "/:", with: "", options: .anchored)
         lPath = lPath.replacingOccurrences(of: "//", with: "", options: .anchored)
         self.init(baseURL: baseURL, name: name, path: lPath)
         self.size = (json["size"] as? NSNumber)?.int64Value ?? -1
-        self.modifiedDate = resolve(dateString: json["lastModifiedDateTime"] as? String ?? "")
-        self.creationDate = resolve(dateString: json["createdDateTime"] as? String ?? "")
-        self.type = (json["folder"] as? String) != nil ? .directory : .regular
+        self.modifiedDate = Date(rfcString: json["lastModifiedDateTime"] as? String ?? "")
+        self.creationDate = Date(rfcString: json["createdDateTime"] as? String ?? "")
+        self.type = json["folder"] != nil ? .directory : .regular
         self.id = json["id"] as? String
         self.entryTag = json["eTag"] as? String
     }
@@ -61,20 +62,20 @@ public final class OneDriveFileObject: FileObject {
     /// MIME type of file contents returned by OneDrive server.
     open internal(set) var contentType: String {
         get {
-            return allValues[.mimeType] as? String ?? ""
+            return allValues[.mimeTypeKey] as? String ?? ""
         }
         set {
-            allValues[.mimeType] = newValue
+            allValues[.mimeTypeKey] = newValue
         }
     }
     
     /// HTTP E-Tag, can be used to mark changed files.
     open internal(set) var entryTag: String? {
         get {
-            return allValues[.entryTag] as? String
+            return allValues[.entryTagKey] as? String
         }
         set {
-            allValues[.entryTag] = newValue
+            allValues[.entryTagKey] = newValue
         }
     }
 }
@@ -85,7 +86,7 @@ internal extension OneDriveFileProvider {
         let url = cursor ?? self.url(of: path, modifier: "children")
         var request = URLRequest(url: url)
         request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             var responseError: FileProviderOneDriveError?
             var files = prevContents
@@ -113,67 +114,69 @@ internal extension OneDriveFileProvider {
         task.resume()
     }
     
-    func upload_simple(_ targetPath: String, data: Data, modifiedDate: Date = Date(), overwrite: Bool, operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        if data.count > 100 * 1024 * 1024 {
-            let error = FileProviderOneDriveError(code: .payloadTooLarge, path: targetPath, errorDescription: nil)
-            completionHandler?(error)
-            self.delegateNotify(.create(path: targetPath), error: error)
-            return nil
-        }
-        let queryStr = overwrite ? "" : "?@name.conflictBehavior=fail"
-        let url = self.url(of: targetPath, modifier: "content\(queryStr)")
-        var request = URLRequest(url: url)
-        request.httpMethod = "PUT"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/octet-stream", forHTTPHeaderField: "Content-Type")
-        request.httpBody = data
-        let task = session.uploadTask(with: request, from: data, completionHandler: { (data, response, error) in
-            var responseError: FileProviderOneDriveError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderOneDriveError(code: rCode, path: targetPath, errorDescription: String(data: data ?? Data(), encoding: .utf8))
-            }
-            completionHandler?(responseError ?? error)
-            self.delegateNotify(operation, error: responseError ?? error)
-        })
-        task.taskDescription = operation.json
-        task.resume()
-        return RemoteOperationHandle(operationType: operation, tasks: [task])
-    }
-    
-    func upload_simple(_ targetPath: String, localFile: URL, modifiedDate: Date = Date(), overwrite: Bool, operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let size = (try? localFile.resourceValues(forKeys: [.fileSizeKey]))?.fileSize ?? -1
+    func upload_simple(_ targetPath: String, data: Data? = nil, localFile: URL? = nil, modifiedDate: Date = Date(), overwrite: Bool, operation: FileOperationType, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let size = data?.count ?? (try? localFile?.resourceValues(forKeys: [.fileSizeKey]))??.fileSize ?? -1
         if size > 100 * 1024 * 1024 {
             let error = FileProviderOneDriveError(code: .payloadTooLarge, path: targetPath, errorDescription: nil)
             completionHandler?(error)
             self.delegateNotify(.create(path: targetPath), error: error)
             return nil
         }
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(operation, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        progress.totalUnitCount = Int64(size)
+        
         let queryStr = overwrite ? "" : "?@name.conflictBehavior=fail"
         let url = self.url(of: targetPath, modifier: "content\(queryStr)")
         var request = URLRequest(url: url)
         request.httpMethod = "PUT"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
-        request.setValue("application/octet-stream", forHTTPHeaderField: "Content-Type")
-        let task = session.uploadTask(with: request, fromFile: localFile, completionHandler: { (data, response, error) in
+        request.set(httpAuthentication: credential, with: .oAuth2)
+        request.set(contentType: .stream)
+        let task: URLSessionUploadTask
+        if let data = data {
+            task = session.uploadTask(with: request, from: data)
+        } else if  let localFile = localFile {
+            task = session.uploadTask(with: request, fromFile: localFile)
+        } else {
+            return nil
+        }
+        
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { [weak self] error in
             var responseError: FileProviderOneDriveError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderOneDriveError(code: rCode, path: targetPath, errorDescription: String(data: data ?? Data(), encoding: .utf8))
+            if let code = (task.response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
+                // We can't fetch server result from delegate!
+                responseError = FileProviderOneDriveError(code: rCode, path: targetPath, errorDescription: nil)
+            }
+            if !(responseError == nil && error == nil) {
+                progress.cancel()
             }
             completionHandler?(responseError ?? error)
-            self.delegateNotify(operation, error: responseError ?? error)
-        })
+            self?.delegateNotify(.create(path: targetPath), error: responseError ?? error)
+        }
         task.taskDescription = operation.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesSent), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: operation, tasks: [task])
+        return progress
     }
     
-    func search(_ startPath: String = "", query: String, next: URL? = nil, foundItem:@escaping ((_ file: OneDriveFileObject) -> Void), completionHandler: @escaping ((_ error: Error?) -> Void)) {
+    func search(_ startPath: String = "", query: String, next: URL? = nil, progress: Progress, foundItem: @escaping ((_ file: OneDriveFileObject) -> Void), completionHandler: @escaping ((_ error: Error?) -> Void)) {
+        if progress.isCancelled {
+            return
+        }
+        
         let url: URL
         let q = query.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!
         url = next ?? self.url(of: startPath, modifier: "view.search?q=\(q)")
         var request = URLRequest(url: url)
         request.httpMethod = "GET"
-        request.setValue("Bearer \(credential?.password ?? "")", forHTTPHeaderField: "Authorization")
+        request.set(httpAuthentication: credential, with: .oAuth2)
         
         let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
             var responseError: FileProviderOneDriveError?
@@ -188,8 +191,8 @@ internal extension OneDriveFileProvider {
                         }
                     }
                     let next: URL? = (json["@odata.nextLink"] as? String).flatMap { URL(string: $0) }
-                    if let next = next {
-                        self.search(startPath, query: query, next: next, foundItem: foundItem, completionHandler: completionHandler)
+                    if !progress.isCancelled, let next = next {
+                        self.search(startPath, query: query, next: next, progress: progress, foundItem: foundItem, completionHandler: completionHandler)
                     } else {
                         completionHandler(responseError ?? error)
                     }
@@ -197,7 +200,11 @@ internal extension OneDriveFileProvider {
                 }
             }
             completionHandler(responseError ?? error)
-        }) 
+        })
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
     }
 }
@@ -240,14 +247,14 @@ internal extension OneDriveFileProvider {
         if let location = json["location"] as? [String: Any], let latitude = location["latitude"] as? Double, let longitude = location["longitude"] as? Double {
             OneDriveFileProvider.decimalFormatter.numberStyle = .decimal
             OneDriveFileProvider.decimalFormatter.maximumFractionDigits = 5
-            let latStr = OneDriveFileProvider.decimalFormatter.string(from: NSNumber(value: latitude))
-            let longStr = OneDriveFileProvider.decimalFormatter.string(from: NSNumber(value: longitude))
+            let latStr = OneDriveFileProvider.decimalFormatter.string(from: NSNumber(value: latitude))!
+            let longStr = OneDriveFileProvider.decimalFormatter.string(from: NSNumber(value: longitude))!
             add(key: "Location", value: "\(latStr), \(longStr)")
         }
         if let parent = json["image"] as? [String: Any] ?? json["video"] as? [String: Any], let duration = parent["duration"] as? UInt64 {
             add(key: "Duration", value: (TimeInterval(duration) / 1000).formatshort)
         }
-        if let timeTakenStr = json["takenDateTime"] as? String, let timeTaken = resolve(dateString: timeTakenStr) {
+        if let timeTakenStr = json["takenDateTime"] as? String, let timeTaken = Date(rfcString: timeTakenStr) {
             OneDriveFileProvider.dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
             add(key: "Date taken", value:  OneDriveFileProvider.dateFormatter.string(from: timeTaken))
         }

Sources/RemoteSession.swift

@@ -8,63 +8,11 @@
 
 import Foundation
 
-/// Allows to get progress or cancel an in-progress operation, for remote, `URLSession` based providers.
-open class RemoteOperationHandle: OperationHandle {
-    
-    internal var tasks: [Weak<URLSessionTask>]
-    
-    open private(set) var operationType: FileOperationType
-    
-    init(operationType: FileOperationType, tasks: [URLSessionTask]) {
-        self.operationType = operationType
-        self.tasks = tasks.map { Weak<URLSessionTask>($0) }
-    }
-    
-    internal func add(task: URLSessionTask) {
-        tasks.append(Weak<URLSessionTask>(task))
-    }
-    
-    private func reape() {
-        self.tasks = tasks.filter { $0.value != nil }
-    }
-    
-    open var bytesSoFar: Int64 {
-        return tasks.reduce(0) {
-            if let task = $1.value as? URLSessionUploadTask {
-                return $0 + task.countOfBytesSent
-            } else {
-                return $0 + ($1.value?.countOfBytesReceived ?? 0)
-            }
-        }
-    }
-    
-    open var totalBytes: Int64 {
-        return tasks.reduce(0) {
-            if let task = $1.value as? URLSessionUploadTask {
-                return $0 + task.countOfBytesExpectedToSend
-            } else {
-                return $0 + ($1.value?.countOfBytesExpectedToReceive ?? 0)
-            }
-        }
-    }
-    
-    open func cancel() -> Bool {
-        var canceled = false
-        for taskbox in tasks {
-            taskbox.value?.cancel()
-            canceled = true
-        }
-        return canceled
-    }
-    
-    open var inProgress: Bool {
-        return tasks.reduce(false) { $0 || $1.value?.state ?? .canceling == .running }
-    }
-}
-
 /// A protocol defines properties for errors returned by HTTP/S based providers.
 /// Including Dropbox, OneDrive and WebDAV.
 public protocol FileProviderHTTPError: Error, CustomStringConvertible {
+    /// HTTP status codes as an enum.
+    typealias Code = FileProviderHTTPErrorCode
     /// HTTP status code returned for error by server.
     var code: FileProviderHTTPErrorCode { get }
     /// Path of file/folder casued that error
@@ -83,27 +31,142 @@ extension FileProviderHTTPError {
     }
 }
 
-class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionDownloadDelegate {
+/// Defines HTTP Authentication method required to access
+public enum HTTPAuthenticationType {
+    /// Basic method for authentication
+    case basic
+    /// Digest method for authentication
+    case digest
+    /// OAuth 1.0 method for authentication (OAuth)
+    case oAuth1
+    /// OAuth 2.0 method for authentication (Bearer)
+    case oAuth2
+}
+
+internal var completionHandlersForTasks = [String: [Int: SimpleCompletionHandler]]()
+internal var downloadCompletionHandlersForTasks = [String: [Int: (URL) -> Void]]()
+internal var dataCompletionHandlersForTasks = [String: [Int: (Data) -> Void]]()
+
+internal func initEmptySessionHandler(_ uuid: String) {
+    completionHandlersForTasks[uuid] = [:]
+    downloadCompletionHandlersForTasks[uuid] = [:]
+    dataCompletionHandlersForTasks[uuid] = [:]
+}
+
+internal func removeSessionHandler(for uuid: String) {
+    _ = completionHandlersForTasks.removeValue(forKey: uuid)
+    _ = downloadCompletionHandlersForTasks.removeValue(forKey: uuid)
+    _ = dataCompletionHandlersForTasks.removeValue(forKey: uuid)
+}
+
+/// All objects set to `FileProviderRemote.session` must be an instance of this class
+final public class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionDownloadDelegate, URLSessionStreamDelegate {
     
     weak var fileProvider: (FileProviderBasicRemote & FileProviderOperations)?
     var credential: URLCredential?
     
-    var finishDownloadHandler: ((_ session: Foundation.URLSession, _ downloadTask: URLSessionDownloadTask, _ didFinishDownloadingToURL: URL) -> Void)?
-    var didSendDataHandler: ((_ session: Foundation.URLSession, _ task: URLSessionTask, _ bytesSent: Int64, _ totalBytesSent: Int64, _ totalBytesExpectedToSend: Int64) -> Void)?
-    var didReceivedData: ((_ session: Foundation.URLSession, _ downloadTask: URLSessionDownloadTask, _ bytesWritten: Int64, _ totalBytesWritten: Int64, _ totalBytesExpectedToWrite: Int64) -> Void)?
+    /// Forwardng URLSessionDownloadTaskDelegate call
+    public var finishDownloadHandler: ((_ session: URLSession, _ downloadTask: URLSessionDownloadTask, _ didFinishDownloadingToURL: URL) -> Void)?
+    /// Forwardng URLSessionTaskDelegate call
+    public var didSendDataHandler: ((_ session: URLSession, _ task: URLSessionTask, _ bytesSent: Int64, _ totalBytesSent: Int64, _ totalBytesExpectedToSend: Int64) -> Void)?
+    /// Forwardng URLSessionDownloadTaskDelegate call
+    public var didReceivedData: ((_ session: URLSession, _ downloadTask: URLSessionDownloadTask, _ bytesWritten: Int64, _ totalBytesWritten: Int64, _ totalBytesExpectedToWrite: Int64) -> Void)?
+    /// Forwardng URLSessionStreamTaskDelegate call
+    public var didBecomeStream :((_ session: URLSession, _ taskId: Int, _ didBecome: InputStream, _ outputStream: OutputStream) -> Void)?
     
-    init(fileProvider: FileProviderBasicRemote & FileProviderOperations, credential: URLCredential?) {
+    public init(fileProvider: FileProviderBasicRemote & FileProviderOperations) {
         self.fileProvider = fileProvider
-        self.credential = credential
+        self.credential = fileProvider.credential
+    }
+    
+    open override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
+        if let progress = context?.load(as: Progress.self), let newVal = change?[.newKey] as? Int64 {
+            switch keyPath ?? "" {
+            case #keyPath(URLSessionTask.countOfBytesReceived):
+                progress.completedUnitCount = newVal
+                if let startTime = progress.userInfo[ProgressUserInfoKey.startingTimeKey] as? Date, let task = object as? URLSessionTask {
+                    let elapsed = Date().timeIntervalSince(startTime)
+                    let throughput = Double(newVal) / elapsed
+                    progress.setUserInfoObject(NSNumber(value: throughput), forKey: .throughputKey)
+                    if task.countOfBytesExpectedToReceive > 0 {
+                        let remain = task.countOfBytesExpectedToReceive - task.countOfBytesReceived
+                        let estimatedTimeRemaining = Double(remain) / elapsed
+                        progress.setUserInfoObject(NSNumber(value: estimatedTimeRemaining), forKey: .estimatedTimeRemainingKey)
+                    }
+                }
+            case #keyPath(URLSessionTask.countOfBytesSent):
+                progress.completedUnitCount = newVal
+                if let startTime = progress.userInfo[ProgressUserInfoKey.startingTimeKey] as? Date, let task = object as? URLSessionTask {
+                    let elapsed = Date().timeIntervalSince(startTime)
+                    let throughput = Double(newVal) / elapsed
+                    progress.setUserInfoObject(NSNumber(value: throughput), forKey: .throughputKey)
+                    if task.countOfBytesExpectedToSend > 0 {
+                        let remain = task.countOfBytesExpectedToSend - task.countOfBytesSent
+                        let estimatedTimeRemaining = Double(remain) / elapsed
+                        progress.setUserInfoObject(NSNumber(value: estimatedTimeRemaining), forKey: .estimatedTimeRemainingKey)
+                    }
+                }
+            case #keyPath(URLSessionTask.countOfBytesExpectedToReceive), #keyPath(URLSessionTask.countOfBytesExpectedToSend):
+                progress.totalUnitCount = newVal
+            default:
+                break
+            }
+        }
+        super.observeValue(forKeyPath: keyPath, of: object, change: change, context: context)
     }
     
     // codebeat:disable[ARITY]
-    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) {
-        self.finishDownloadHandler?(session, downloadTask, location)
-        return
+    public func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
+        task.removeObserver(self, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived))
+        task.removeObserver(self, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive))
+        task.removeObserver(self, forKeyPath: #keyPath(URLSessionTask.countOfBytesSent))
+        task.removeObserver(self, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived))
+        
+        if !(error == nil && task is URLSessionDownloadTask) {
+            let completionHandler = completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] ?? nil
+            completionHandler?(error)
+            _ = completionHandlersForTasks[session.sessionDescription!]?.removeValue(forKey: task.taskIdentifier)
+        }
+        
+        guard let json = task.taskDescription?.deserializeJSON(),
+            let op = FileOperationType(json: json), let fileProvider = fileProvider else {
+                return
+        }
+        
+        if !(task is URLSessionDownloadTask), case FileOperationType.fetch = op {
+            return
+        }
+        if #available(iOS 9.0, macOS 10.11, *) {
+            if task is URLSessionStreamTask {
+                return
+            }
+        }
+        
+        DispatchQueue.main.async {
+            if error != nil {
+                fileProvider.delegate?.fileproviderFailed(fileProvider, operation: op)
+            } else {
+                fileProvider.delegate?.fileproviderSucceed(fileProvider, operation: op)
+            }
+        }
     }
     
-    func urlSession(_ session: URLSession, task: URLSessionTask, didSendBodyData bytesSent: Int64, totalBytesSent: Int64, totalBytesExpectedToSend: Int64) {
+    public func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive data: Data) {
+        let completionHandler = dataCompletionHandlersForTasks[session.sessionDescription!]?[dataTask.taskIdentifier] ?? nil
+        completionHandler?(data)
+        _ = dataCompletionHandlersForTasks[session.sessionDescription!]?.removeValue(forKey: dataTask.taskIdentifier)
+    }
+    
+    public func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) {
+        self.finishDownloadHandler?(session, downloadTask, location)
+        
+        let dcompletionHandler = downloadCompletionHandlersForTasks[session.sessionDescription!]?[downloadTask.taskIdentifier]
+        dcompletionHandler?(location)
+        _ = downloadCompletionHandlersForTasks[session.sessionDescription!]?.removeValue(forKey: downloadTask.taskIdentifier)
+        _ = completionHandlersForTasks[session.sessionDescription!]?.removeValue(forKey: downloadTask.taskIdentifier)
+    }
+    
+    public func urlSession(_ session: URLSession, task: URLSessionTask, didSendBodyData bytesSent: Int64, totalBytesSent: Int64, totalBytesExpectedToSend: Int64) {
         self.didSendDataHandler?(session, task, bytesSent, totalBytesSent, totalBytesExpectedToSend)
         
         guard let json = task.taskDescription?.deserializeJSON(),
@@ -111,12 +174,23 @@ class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionDownloadDeleg
             return
         }
         
+        switch op {
+        case .create(path: let path):
+            if path.hasSuffix("/") { return }
+        case .modify:
+            break
+        default:
+            return
+        }
+        
         let progress = Float(totalBytesSent) / Float(totalBytesExpectedToSend)
         
-        fileProvider.delegate?.fileproviderProgress(fileProvider, operation: op, progress: progress)
+        DispatchQueue.main.async {
+            fileProvider.delegate?.fileproviderProgress(fileProvider, operation: op, progress: progress)
+        }
     }
     
-    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64) {
+    public func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64) {
         self.didReceivedData?(session, downloadTask, bytesWritten, totalBytesWritten, totalBytesExpectedToWrite)
         
         guard let json = downloadTask.taskDescription?.deserializeJSON(),
@@ -124,14 +198,16 @@ class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionDownloadDeleg
             return
         }
         
-        fileProvider.delegate?.fileproviderProgress(fileProvider, operation: op, progress: Float(totalBytesWritten) / Float(totalBytesExpectedToWrite))
+        DispatchQueue.main.async {
+            fileProvider.delegate?.fileproviderProgress(fileProvider, operation: op, progress: Float(totalBytesWritten) / Float(totalBytesExpectedToWrite))
+        }
     }
     
-    func urlSession(_ session: URLSession, task: URLSessionTask, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
+    public func urlSession(_ session: URLSession, task: URLSessionTask, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
         authenticate(didReceive: challenge, completionHandler: completionHandler)
     }
     
-    func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
+    public func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
         authenticate(didReceive: challenge, completionHandler: completionHandler)
     }
     
@@ -145,6 +221,11 @@ class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionDownloadDeleg
             completionHandler(.performDefaultHandling, nil)
         }
     }
+    
+    @available(iOS 9.0, macOS 10.11, *)
+    public func urlSession(_ session: URLSession, streamTask: URLSessionStreamTask, didBecome inputStream: InputStream, outputStream: OutputStream) {
+        self.didBecomeStream?(session, streamTask.taskIdentifier, inputStream, outputStream)
+    }
 }
 
 /// HTTP status codes as an enum.

Sources/SMBClient.swift

@@ -11,11 +11,11 @@ import Foundation
 // This client implementation is for little-endian platform, namely x86, x64 & arm
 // For big-endian platforms like PowerPC, there must be a huge overhaul
 
-protocol SMBProtocolClientDelegate: class {
-    func receivedResponse(client: SMB2ProtocolClient, response: SMBResponse, for: SMBRequest)
+protocol FileProviderSMBTaskDelegate: class {
+    func receivedResponse(client: FileProviderSMBTask, response: SMBResponse, for: SMBRequest)
 }
 
-class SMB2ProtocolClient: FPSStreamTask {
+class FileProviderSMBTask: FileProviderStreamTask {
     var timeout: TimeInterval = 30
     
     private(set) var lastMessageID: UInt64 = 0
@@ -31,14 +31,14 @@ class SMB2ProtocolClient: FPSStreamTask {
     private(set) var requestStack = [Int: SMBRequest]()
     private(set) var responseStack = [Int: SMBResponse]()
     
-    weak var delegate: SMBProtocolClientDelegate?
+    weak var delegate: FileProviderSMBTaskDelegate?
     
     func sendNegotiate(completionHandler: SimpleCompletionHandler) -> UInt64 {
         let mId = messageId()
         let smbHeader = SMB2.Header(command: .NEGOTIATE, creditRequestResponse: UInt16(126), messageId: mId, treeId: UInt32(0), sessionId: UInt64(0))
         let msg = SMB2.NegotiateRequest()
         let data = createSMB2Message(header: smbHeader, message: msg)
-        self.writeData(data, timeout: 0, completionHandler: { (e) in
+        self.write(data, timeout: timeout, completionHandler: { (e) in
             completionHandler?(e)
         })
         return mId
@@ -50,9 +50,9 @@ class SMB2ProtocolClient: FPSStreamTask {
         let smbHeader = SMB2.Header(command: SMB2.Command.SESSION_SETUP, creditRequestResponse: credit, messageId: mId, treeId: UInt32(0), sessionId: sessionId)
         let msg = SMB2.SessionSetupRequest(singing: [])
         let data = createSMB2Message(header: smbHeader, message: msg)
-        self.writeData(data, timeout: 0, completionHandler: { (e) in
+        self.write(data, timeout: timeout, completionHandler: { (e) in
             if self.sessionId == 0 {
-                self.readData(OfMinLength: 64, maxLength: 65536, timeout: self.timeout, completionHandler: { (data, eof, e2) in
+                self.readData(ofMinLength: 64, maxLength: 65536, timeout: self.timeout, completionHandler: { (data, eof, e2) in
                     // TODO: set session id
                     completionHandler?(e2 ?? e)
                 })
@@ -73,7 +73,7 @@ class SMB2ProtocolClient: FPSStreamTask {
         let tcHeader = SMB2.TreeConnectRequest.Header(flags: [])
         let msg = SMB2.TreeConnectRequest(header: tcHeader, host: host, share: share)
         let data = createSMB2Message(header: smbHeader, message: msg!)
-        self.writeData(data, timeout: 0, completionHandler: { (e) in
+        self.write(data, timeout: timeout, completionHandler: { (e) in
             completionHandler?(e)
             
         })
@@ -85,7 +85,7 @@ class SMB2ProtocolClient: FPSStreamTask {
         let smbHeader = SMB2.Header(command: .TREE_DISCONNECT, creditRequestResponse: 111, messageId: mId, treeId: treeId, sessionId: sessionId)
         let msg = SMB2.TreeDisconnect()
         let data = createSMB2Message(header: smbHeader, message: msg)
-        self.writeData(data, timeout: 0, completionHandler: { (e) in
+        self.write(data, timeout: timeout, completionHandler: { (e) in
             completionHandler?(e)
         })
         return mId
@@ -96,7 +96,7 @@ class SMB2ProtocolClient: FPSStreamTask {
         let smbHeader = SMB2.Header(command: .LOGOFF, creditRequestResponse: 0, messageId: mId, treeId: 0, sessionId: sessionId)
         let msg = SMB2.LogOff()
         let data = createSMB2Message(header: smbHeader, message: msg)
-        self.writeData(data, timeout: 0, completionHandler: { (e) in
+        self.write(data, timeout: timeout, completionHandler: { (e) in
             completionHandler?(e)
         })
         return mId
@@ -108,7 +108,7 @@ class SMB2ProtocolClient: FPSStreamTask {
 }
 
 // MARK: create and analyse messages
-extension SMB2ProtocolClient {
+extension FileProviderSMBTask {
     func determineSMBVersion(_ data: Data) -> Float {
         let smbverChar: Int8 = Int8(bitPattern: data.first ?? 0)
         let version = 0 - smbverChar

Sources/SMBFileProvider.swift

@@ -15,7 +15,7 @@ class SMBFileProvider: FileProvider, FileProviderMonitor {
     open var dispatch_queue: DispatchQueue
     open var operation_queue: OperationQueue
     open weak var delegate: FileProviderDelegate?
-    open let credential: URLCredential?
+    open var credential: URLCredential?
     
     public typealias FileObjectClass = FileObject
     
@@ -24,9 +24,15 @@ class SMBFileProvider: FileProvider, FileProviderMonitor {
             return nil
         }
         self.baseURL = baseURL.appendingPathComponent("")
-        dispatch_queue = DispatchQueue(label: "FileProvider.\(type(of: self).type)", attributes: .concurrent)
+        
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
         operation_queue = OperationQueue()
-        operation_queue.name = "FileProvider.\(type(of: self).type).Operation"
+        operation_queue.name = "\(queueLabel).Operation"
         
         self.credential = credential
     }
@@ -68,60 +74,56 @@ class SMBFileProvider: FileProvider, FileProviderMonitor {
     
     open weak var fileOperationDelegate: FileOperationDelegate?
     
-    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func create(file fileName: String, at atPath: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func contents(path: String, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func writeContents(path: String, contents data: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler:((FileObjectClass) -> Void)?, completionHandler: @escaping ((_ files: [FileObjectClass], _ error: Error?) -> Void)) -> Progress? {
         NotImplemented()
         return nil
     }
     
-    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler:((FileObjectClass) -> Void)?, completionHandler: @escaping ((_ files: [FileObjectClass], _ error: Error?) -> Void)) {
-        NotImplemented()
-    }
-    
     open func registerNotifcation(path: String, eventHandler: @escaping (() -> Void)) {
         NotImplemented()
     }

Sources/WebDAVFileProvider.swift

@@ -7,12 +7,13 @@
 //
 
 import Foundation
+import CoreGraphics
 
 /**
  Allows accessing to WebDAV server files. This provider doesn't cache or save files internally, however you can
  set `useCache` and `cache` properties to use Foundation `NSURLCache` system.
  
- WebDAV system supported by many cloud services including [Box.net](https://www.box.com/home) 
+ WebDAV system supported by many cloud services including [Box.com](https://www.box.com/home) 
  and [Yandex disk](https://disk.yandex.com) and [ownCloud](https://owncloud.org).
  
  - Important: Because this class uses `URLSession`, it's necessary to disable App Transport Security
@@ -32,7 +33,12 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
     }
     
     public weak var delegate: FileProviderDelegate?
-    open let credential: URLCredential?
+    public var credentialType: HTTPAuthenticationType = .digest
+    open var credential: URLCredential? {
+        didSet {
+            sessionDelegate?.credential = credential
+        }
+    }
     open private(set) var cache: URLCache?
     public var useCache: Bool
     public var validatingCache: Bool
@@ -40,16 +46,30 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
     fileprivate var _session: URLSession?
     fileprivate var sessionDelegate: SessionDelegate?
     public var session: URLSession {
-        if _session == nil {
-            self.sessionDelegate = SessionDelegate(fileProvider: self, credential: credential)
-            let queue = OperationQueue()
-            //queue.underlyingQueue = dispatch_queue
-            let config = URLSessionConfiguration.default
-            config.urlCache = cache
-            config.requestCachePolicy = .returnCacheDataElseLoad
-            _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDownloadDelegate?, delegateQueue: queue)
+        get {
+            if _session == nil {
+                self.sessionDelegate = SessionDelegate(fileProvider: self)
+                let queue = OperationQueue()
+                //queue.underlyingQueue = dispatch_queue
+                let config = URLSessionConfiguration.default
+                config.urlCache = cache
+                config.requestCachePolicy = .returnCacheDataElseLoad
+                _session = URLSession(configuration: config, delegate: sessionDelegate as URLSessionDownloadDelegate?, delegateQueue: queue)
+                _session?.sessionDescription = UUID().uuidString
+                initEmptySessionHandler(_session!.sessionDescription!)
+            }
+            return _session!
+        }
+        
+        set {
+            assert(newValue.delegate is SessionDelegate, "session instances should have a SessionDelegate instance as delegate.")
+            _session = newValue
+            if session.sessionDescription?.isEmpty ?? true {
+                _session?.sessionDescription = UUID().uuidString
+            }
+            self.sessionDelegate = newValue.delegate as? SessionDelegate
+            initEmptySessionHandler(_session!.sessionDescription!)
         }
-        return _session!
     }
     
     /**
@@ -64,15 +84,21 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
         if  !["http", "https"].contains(baseURL.uw_scheme.lowercased()) {
             return nil
         }
-        self.baseURL = baseURL.path.hasSuffix("/") ? baseURL : baseURL.appendingPathComponent("")
+        self.baseURL = (baseURL.absoluteString.hasSuffix("/") ? baseURL : baseURL.appendingPathComponent("")).absoluteURL
         self.currentPath = ""
         self.useCache = false
         self.validatingCache = true
         self.cache = cache
         self.credential = credential
-        dispatch_queue = DispatchQueue(label: "FileProvider.\(type(of: self).type)", attributes: .concurrent)
+        
+        #if swift(>=3.1)
+        let queueLabel = "FileProvider.\(Swift.type(of: self).type)"
+        #else
+        let queueLabel = "FileProvider.\(type(of: self).type)"
+        #endif
+        dispatch_queue = DispatchQueue(label: queueLabel, attributes: .concurrent)
         operation_queue = OperationQueue()
-        operation_queue.name = "FileProvider.\(type(of: self).type).Operation"
+        operation_queue.name = "\(queueLabel).Operation"
     }
     
     public required convenience init?(coder aDecoder: NSCoder) {
@@ -90,8 +116,8 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
         aCoder.encode(self.baseURL, forKey: "baseURL")
         aCoder.encode(self.credential, forKey: "credential")
         aCoder.encode(self.currentPath, forKey: "currentPath")
-        aCoder.encode(self.useCache, forKey: "isCoorinating")
-        aCoder.encode(self.validatingCache, forKey: "undoManager")
+        aCoder.encode(self.useCache, forKey: "useCache")
+        aCoder.encode(self.validatingCache, forKey: "validatingCache")
     }
     
     public static var supportsSecureCoding: Bool {
@@ -109,6 +135,10 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
     }
     
     deinit {
+        if let sessionuuid = _session?.sessionDescription {
+            removeSessionHandler(for: sessionuuid)
+        }
+        
         if fileProviderCancelTasksOnInvalidating {
             _session?.invalidateAndCancel()
         } else {
@@ -116,16 +146,32 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
         }
     }
     
-    open func contentsOfDirectory(path: String, completionHandler: @escaping ((_ contents: [FileObject], _ error: Error?) -> Void)) {
+    open func contentsOfDirectory(path: String, completionHandler: @escaping (([FileObject], Error?) -> Void)) {
+        self.contentsOfDirectory(path: path, including: [], completionHandler: completionHandler)
+    }
+    
+    /**
+     Returns an Array of `FileObject`s identifying the the directory entries via asynchronous completion handler.
+     
+     If the directory contains no entries or an error is occured, this method will return the empty array.
+     
+     - Parameter path: path to target directory. If empty, `currentPath` value will be used.
+     - Parameter including: An array which determines which file properties should be considered to fetch.
+     - Parameter completionHandler: a closure with result of directory entries or error.
+         - `contents`: An array of `FileObject` identifying the the directory entries.
+         - `error`: Error returned by system.
+     */
+    open func contentsOfDirectory(path: String, including: [URLResourceKey], completionHandler: @escaping ((_ contents: [FileObject], _ error: Error?) -> Void)) {
         let opType = FileOperationType.fetch(path: path)
         let url = self.url(of: path).appendingPathComponent("")
         var request = URLRequest(url: url)
         request.httpMethod = "PROPFIND"
         request.setValue("1", forHTTPHeaderField: "Depth")
-        request.setValue("text/xml; charset=\"utf-8\"", forHTTPHeaderField: "Content-Type")
-        request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:allprop/></D:propfind>".data(using: .utf8)
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(contentType: .xml)
+        request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n\(WebDavFileObject.propString(including))\n</D:propfind>".data(using: .utf8)
         request.setValue(String(request.httpBody!.count), forHTTPHeaderField: "Content-Length")
-        runDataTask(with: request, operationHandle: RemoteOperationHandle(operationType: opType, tasks: []), completionHandler: { (data, response, error) in
+        runDataTask(with: request, operation: opType, completionHandler: { (data, response, error) in
             var responseError: FileProviderWebDavError?
             if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
                 responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
@@ -145,12 +191,28 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
     }
     
     open func attributesOfItem(path: String, completionHandler: @escaping ((_ attributes: FileObject?, _ error: Error?) -> Void)) {
+        self.attributesOfItem(path: path, including: [], completionHandler: completionHandler)
+    }
+    
+    /**
+     Returns a `FileObject` containing the attributes of the item (file, directory, symlink, etc.) at the path in question via asynchronous completion handler.
+     
+     If the directory contains no entries or an error is occured, this method will return the empty `FileObject`.
+     
+     - Parameter path: path to target directory. If empty, `currentPath` value will be used.
+     - Parameter including: An array which determines which file properties should be considered to fetch.
+     - Parameter completionHandler: a closure with result of directory entries or error.
+         - `attributes`: A `FileObject` containing the attributes of the item.
+         - `error`: Error returned by system.
+     */
+    open func attributesOfItem(path: String, including: [URLResourceKey], completionHandler: @escaping ((_ attributes: FileObject?, _ error: Error?) -> Void)) {
         let url = self.url(of: path)
         var request = URLRequest(url: url)
         request.httpMethod = "PROPFIND"
         request.setValue("1", forHTTPHeaderField: "Depth")
-        request.setValue("text/xml; charset=\"utf-8\"", forHTTPHeaderField: "Content-Type")
-        request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:allprop/></D:propfind>".data(using: .utf8)
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(contentType: .xml)
+        request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n\(WebDavFileObject.propString(including))\n</D:propfind>".data(using: .utf8)
         request.setValue(String(request.httpBody!.count), forHTTPHeaderField: "Content-Length")
         runDataTask(with: request, completionHandler: { (data, response, error) in
             var responseError: FileProviderWebDavError?
@@ -178,7 +240,8 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
         var request = URLRequest(url: baseURL)
         request.httpMethod = "PROPFIND"
         request.setValue("0", forHTTPHeaderField: "Depth")
-        request.setValue("text/xml; charset=\"utf-8\"", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(contentType: .xml)
         request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:prop><D:quota-available-bytes/><D:quota-used-bytes/></D:prop>\n</D:propfind>".data(using: .utf8)
         request.setValue(String(request.httpBody!.count), forHTTPHeaderField: "Content-Length")
         runDataTask(with: request, completionHandler: { (data, response, error) in
@@ -195,14 +258,16 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
         })
     }
     
-    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) {
+    open func searchFiles(path: String, recursive: Bool, query: NSPredicate, foundItemHandler: ((FileObject) -> Void)?, completionHandler: @escaping ((_ files: [FileObject], _ error: Error?) -> Void)) -> Progress? {
         let url = self.url(of: path)
         var request = URLRequest(url: url)
         request.httpMethod = "PROPFIND"
         //request.setValue("1", forHTTPHeaderField: "Depth")
-        request.setValue("text/xml; charset=\"utf-8\"", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(contentType: .xml)
         request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:allprop/></D:propfind>".data(using: .utf8)
-        runDataTask(with: request, completionHandler: { (data, response, error) in
+        let progress = Progress(parent: nil, userInfo: nil)
+        let task = session.dataTask(with: request) { (data, response, error) in
             // FIXME: paginating results
             var responseError: FileProviderWebDavError?
             if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
@@ -218,20 +283,28 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
                     }
                     
                     fileObjects.append(fileObject)
+                    progress.completedUnitCount = Int64(fileObjects.count)
                     foundItemHandler?(fileObject)
                 }
                 completionHandler(fileObjects, responseError ?? error)
                 return
             }
             completionHandler([], responseError ?? error)
-        })
+        }
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+        task.resume()
+        return progress
     }
     
     open func isReachable(completionHandler: @escaping (Bool) -> Void) {
         var request = URLRequest(url: baseURL!)
         request.httpMethod = "PROPFIND"
         request.setValue("0", forHTTPHeaderField: "Depth")
-        request.setValue("text/xml; charset=\"utf-8\"", forHTTPHeaderField: "Content-Type")
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(contentType: .xml)
         request.httpBody = "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<D:propfind xmlns:D=\"DAV:\">\n<D:prop><D:quota-available-bytes/><D:quota-used-bytes/></D:prop>\n</D:propfind>".data(using: .utf8)
         request.setValue(String(request.httpBody!.count), forHTTPHeaderField: "Content-Length")
         runDataTask(with: request, completionHandler: { (data, response, error) in
@@ -245,51 +318,16 @@ open class WebDAVFileProvider: FileProviderBasicRemote {
 
 extension WebDAVFileProvider: FileProviderOperations {
     @discardableResult
-    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func create(folder folderName: String, at atPath: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.create(path: (atPath as NSString).appendingPathComponent(folderName) + "/")
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
-        let url = self.url(of: atPath).appendingPathComponent(folderName, isDirectory: true)
-        var request = URLRequest(url: url)
-        request.httpMethod = "MKCOL"
-        let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
-            var responseError: FileProviderWebDavError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderWebDavError(code: rCode, path: url.relativePath, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
-            }
-            completionHandler?(responseError ?? error)
-            self.delegateNotify(opType, error: responseError ?? error)
-        })
-        task.taskDescription = opType.json
-        task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return self.doOperation(operation: opType, overwrite: false, completionHandler: completionHandler)
     }
     
     @discardableResult
-    open func create(file fileName: String, at path: String, contents data: Data?, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let opType = FileOperationType.create(path: (path as NSString).appendingPathComponent(fileName))
-        guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
-            return nil
-        }
-        let url = self.url(of: path).appendingPathComponent(fileName)
-        var request = URLRequest(url: url)
-        request.httpMethod = "PUT"
-        let task = session.uploadTask(with: request, from: data, completionHandler: { (data, response, error) in
-            var responseError: FileProviderWebDavError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
-            }
-            completionHandler?(responseError ?? error)
-            self.delegateNotify(opType, error: responseError ?? error)
-        })
-        task.taskDescription = opType.json
-        task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
-    }
-    
-    @discardableResult
-    open func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func moveItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.move(source: path, destination: toPath)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
@@ -298,7 +336,7 @@ extension WebDAVFileProvider: FileProviderOperations {
     }
     
     @discardableResult
-    open func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(path: String, to toPath: String, overwrite: Bool = false, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.copy(source: path, destination: toPath)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
@@ -307,7 +345,7 @@ extension WebDAVFileProvider: FileProviderOperations {
     }
     
     @discardableResult
-    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func removeItem(path: String, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.remove(path: path)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
@@ -315,7 +353,7 @@ extension WebDAVFileProvider: FileProviderOperations {
         return self.doOperation(operation: opType, completionHandler: completionHandler)
     }
     
-    func doOperation(operation opType: FileOperationType, overwrite: Bool? = nil, completionHandler: SimpleCompletionHandler) -> OperationHandle?  {
+    fileprivate func doOperation(operation opType: FileOperationType, overwrite: Bool? = nil, completionHandler: SimpleCompletionHandler) -> Progress?  {
         let source = opType.source!
         let sourceURL = self.url(of: source)
         var request = URLRequest(url: sourceURL)
@@ -323,6 +361,8 @@ extension WebDAVFileProvider: FileProviderOperations {
             request.setValue(url(of:dest).absoluteString, forHTTPHeaderField: "Destination")
         }
         switch opType {
+        case .create:
+            request.httpMethod = "MKCOL"
         case .copy:
             request.httpMethod = "COPY"
         case .move:
@@ -333,6 +373,12 @@ extension WebDAVFileProvider: FileProviderOperations {
             return nil
         }
         
+        let progress = Progress(totalUnitCount: 1)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
+        request.set(httpAuthentication: credential, with: credentialType)
         if let overwrite = overwrite, !overwrite {
             request.setValue("F", forHTTPHeaderField: "Overwrite")
         }
@@ -347,9 +393,17 @@ extension WebDAVFileProvider: FileProviderOperations {
                     for xresponse in xresponses where (xresponse.status ?? 0) >= 300 {
                         let error = FileProviderWebDavError(code: code, path: source, errorDescription: String(data: data, encoding: .utf8), url: sourceURL)
                         completionHandler?(error)
+                        progress.cancel()
                     }
                 }
             }
+            
+            if responseError == nil && error == nil {
+                progress.completedUnitCount = 1
+            } else {
+                progress.cancel()
+            }
+            
             if (response as? HTTPURLResponse)?.statusCode ?? 0 != FileProviderHTTPErrorCode.multiStatus.rawValue {
                 completionHandler?(responseError ?? error)
             }
@@ -357,68 +411,116 @@ extension WebDAVFileProvider: FileProviderOperations {
             self.delegateNotify(opType, error: responseError ?? error)
         })
         task.taskDescription = opType.json
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
     
     @discardableResult
-    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func copyItem(localFile: URL, to toPath: String, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
+        // check file is not a folder
+        guard (try? localFile.resourceValues(forKeys: [.fileResourceTypeKey]))?.fileResourceType ?? .unknown == .regular else {
+            dispatch_queue.async {
+                completionHandler?(self.throwError(localFile.path, code: URLError.fileIsDirectory))
+            }
+            return nil
+        }
+        
         let opType = FileOperationType.copy(source: localFile.absoluteString, destination: toPath)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        progress.totalUnitCount = localFile.fileSize
+        
         let url = self.url(of:toPath)
         var request = URLRequest(url: url)
         if !overwrite {
             request.setValue("F", forHTTPHeaderField: "Overwrite")
         }
         request.httpMethod = "PUT"
-        let task = session.uploadTask(with: request, fromFile: localFile, completionHandler: { (data, response, error) in
+        request.set(httpAuthentication: credential, with: credentialType)
+        let task = session.uploadTask(with: request, fromFile: localFile)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { [weak self] error in
             var responseError: FileProviderWebDavError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderWebDavError(code: rCode, path: toPath, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
+            if let code = (task.response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
+                // We can't fetch server result from delegate!
+                responseError = FileProviderWebDavError(code: rCode, path: toPath, errorDescription: nil, url: url)
+            }
+            if !(responseError == nil && error == nil) {
+                progress.cancel()
             }
             completionHandler?(responseError ?? error)
-            self.delegateNotify(opType, error: responseError ?? error)
-        }) 
+            self?.delegateNotify(.create(path: toPath), error: responseError ?? error)
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesSent), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
     
     @discardableResult
-    open func copyItem(path: String, toLocalURL: URL, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
-        let opType = FileOperationType.copy(source: path, destination: toLocalURL.absoluteString)
+    open func copyItem(path: String, toLocalURL destURL: URL, completionHandler: SimpleCompletionHandler) -> Progress? {
+        let opType = FileOperationType.copy(source: path, destination: destURL.absoluteString)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         let url = self.url(of:path)
-        let request = URLRequest(url: url)
-        let task = session.downloadTask(with: request, completionHandler: { (sourceFileURL, response, error) in
-            var responseError: FileProviderWebDavError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: nil, url: url)
+        var request = URLRequest(url: url)
+        request.set(httpAuthentication: credential, with: credentialType)
+        let task = session.downloadTask(with: request)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+            if error != nil {
+                progress.cancel()
             }
-            if let sourceFileURL = sourceFileURL {
-                do {
-                    try FileManager.default.copyItem(at: sourceFileURL, to: toLocalURL)
-                } catch let e {
-                    completionHandler?(e)
-                    return
-                }
+            completionHandler?(error)
+        }
+        downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { tempURL in
+            guard let httpResponse = task.response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
+                let code = FileProviderHTTPErrorCode(rawValue: (task.response as? HTTPURLResponse)?.statusCode ?? -1)
+                let serverError : FileProviderWebDavError? = code != nil ? FileProviderWebDavError(code: code!, path: path, errorDescription: code?.description, url: url) : nil
+                completionHandler?(serverError)
+                return
             }
-            completionHandler?(responseError ?? error)
-            self.delegateNotify(opType, error: responseError ?? error)
-        }) 
+            do {
+                try FileManager.default.moveItem(at: tempURL, to: destURL)
+                completionHandler?(nil)
+            } catch let e {
+                completionHandler?(e)
+            }
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
 }
 
 extension WebDAVFileProvider: FileProviderReadWrite {
     @discardableResult
-    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> OperationHandle? {
+    open func contents(path: String, offset: Int64, length: Int, completionHandler: @escaping ((_ contents: Data?, _ error: Error?) -> Void)) -> Progress? {
         if length == 0 || offset < 0 {
             dispatch_queue.async {
                 completionHandler(Data(), nil)
@@ -427,57 +529,94 @@ extension WebDAVFileProvider: FileProviderReadWrite {
         }
         
         let opType = FileOperationType.fetch(path: path)
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        
         let url = self.url(of: path)
         var request = URLRequest(url: url)
-        request.httpMethod = "GET"
-        if length > 0 {
-            request.setValue("bytes=\(offset)-\(offset + length - 1)", forHTTPHeaderField: "Range")
-        } else if offset > 0 && length < 0 {
-            request.setValue("bytes=\(offset)-", forHTTPHeaderField: "Range")
-        }
-        let handle = RemoteOperationHandle(operationType: opType, tasks: [])
-        runDataTask(with: request, operationHandle: handle, completionHandler: { (data, response, error) in
-            var responseError: FileProviderWebDavError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(rangeWithOffset: offset, length: length)
+        
+        let task = session.downloadTask(with: request)
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { error in
+            if error != nil {
+                progress.cancel()
             }
-            completionHandler(data, responseError ?? error)
-        })
-        return handle
+            
+            completionHandler(nil, error)
+        }
+        downloadCompletionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { [weak self] tempURL in
+            guard let httpResponse = task.response as? HTTPURLResponse , httpResponse.statusCode < 300 else {
+                let code = FileProviderHTTPErrorCode(rawValue: (task.response as? HTTPURLResponse)?.statusCode ?? -1)
+                let serverError : FileProviderWebDavError? = code != nil ? FileProviderWebDavError(code: code!, path: path, errorDescription: code?.description, url: url) : nil
+                completionHandler(nil, serverError)
+                return
+            }
+            do {
+                let data = try Data(contentsOf: tempURL)
+                (self?.dispatch_queue ?? DispatchQueue.global()).async {
+                    completionHandler(data, nil)
+                }
+            } catch let e {
+                completionHandler(nil, e)
+            }
+        }
+        task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesReceived), options: .new, context: &progress)
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesExpectedToReceive), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
+        task.resume()
+        return progress
     }
     
     @discardableResult
-    open func writeContents(path: String, contents data: Data, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> OperationHandle? {
+    open func writeContents(path: String, contents data: Data?, atomically: Bool, overwrite: Bool, completionHandler: SimpleCompletionHandler) -> Progress? {
         let opType = FileOperationType.modify(path: path)
         guard fileOperationDelegate?.fileProvider(self, shouldDoOperation: opType) ?? true == true else {
             return nil
         }
+        
+        var progress = Progress(parent: nil, userInfo: nil)
+        progress.setUserInfoObject(opType, forKey: .fileProvderOperationTypeKey)
+        progress.kind = .file
+        progress.setUserInfoObject(Progress.FileOperationKind.downloading, forKey: .fileOperationKindKey)
+        progress.totalUnitCount = Int64(data?.count ?? 0)
+        
         // FIXME: lock destination before writing process
         let url = atomically ? self.url(of: path).appendingPathExtension("tmp") : self.url(of: path)
         var request = URLRequest(url: url)
         request.httpMethod = "PUT"
+        request.set(httpAuthentication: credential, with: credentialType)
         if !overwrite {
             request.setValue("F", forHTTPHeaderField: "Overwrite")
         }
-        let task = session.uploadTask(with: request, from: data, completionHandler: { (data, response, error) in
+        let task = session.uploadTask(with: request, from: data ?? Data())
+        completionHandlersForTasks[session.sessionDescription!]?[task.taskIdentifier] = { [weak self] error in
             var responseError: FileProviderWebDavError?
-            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
-                responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: self.url(of: path))
+            if let code = (task.response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
+                // We can't fetch server result from delegate!
+                responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: nil, url: url)
             }
-            defer {
-                self.delegateNotify(opType, error: responseError ?? error)
+            if !(responseError == nil && error == nil) {
+                progress.cancel()
             }
-            if let error = error {
-                completionHandler?(error)
-                return
-            }
-            if atomically {
-                self.moveItem(path: (path as NSString).appendingPathExtension("tmp")!, to: path, completionHandler: completionHandler)
-            }
-        }) 
+            completionHandler?(responseError ?? error)
+            self?.delegateNotify(opType, error: responseError ?? error)
+        }
         task.taskDescription = opType.json
+        task.addObserver(sessionDelegate!, forKeyPath: #keyPath(URLSessionTask.countOfBytesSent), options: .new, context: &progress)
+        progress.cancellationHandler = { [weak task] in
+            task?.cancel()
+        }
+        progress.setUserInfoObject(Date(), forKey: .startingTimeKey)
         task.resume()
-        return RemoteOperationHandle(operationType: opType, tasks: [task])
+        return progress
     }
     
     /*
@@ -496,6 +635,86 @@ extension WebDAVFileProvider: FileProviderReadWrite {
     // TODO: implements methods for lock mechanism
 }
 
+extension WebDAVFileProvider: ExtendedFileProvider {
+    open func thumbnailOfFileSupported(path: String) -> Bool {
+        guard self.baseURL?.host?.contains("dav.yandex.") ?? false else {
+            return false
+        }
+        let supportedExt: [String] = ["jpg", "jpeg", "png", "gif"]
+        return supportedExt.contains((path as NSString).pathExtension)
+    }
+    
+    open func thumbnailOfFile(path: String, dimension: CGSize?, completionHandler: @escaping ((ImageClass?, Error?) -> Void)) {
+        guard self.baseURL?.host?.contains("dav.yandex.") ?? false else {
+            dispatch_queue.async {
+                completionHandler(nil, self.throwError(path, code: URLError.resourceUnavailable))
+            }
+            return
+        }
+        
+        let dimension = dimension ?? CGSize(width: 64, height: 64)
+        let url = URL(string: self.url(of: path).absoluteString + "?preview&size=\(dimension.width)x\(dimension.height)")!
+        var request = URLRequest(url: url)
+        request.httpMethod = "GET"
+        request.set(httpAuthentication: credential, with: credentialType)
+        let task = session.dataTask(with: request, completionHandler: { (data, response, error) in
+            var responseError: FileProviderWebDavError?
+            if let code = (response as? HTTPURLResponse)?.statusCode , code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
+                responseError = FileProviderWebDavError(code: rCode, path: url.relativePath, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
+                completionHandler(nil, responseError ?? error)
+                return
+            }
+            
+            completionHandler(data.flatMap({ ImageClass(data: $0) }), nil)
+        })
+        task.resume()
+    }
+    
+    open func propertiesOfFileSupported(path: String) -> Bool {
+        return false
+    }
+    
+    open func propertiesOfFile(path: String, completionHandler: @escaping (([String : Any], [String], Error?) -> Void)) {
+        dispatch_queue.async {
+            completionHandler([:], [], self.throwError(path, code: URLError.resourceUnavailable))
+        }
+    }
+}
+
+extension WebDAVFileProvider: FileProviderSharing {
+    open func publicLink(to path: String, completionHandler: @escaping ((URL?, FileObject?, Date?, Error?) -> Void)) {
+        guard self.baseURL?.host?.contains("dav.yandex.") ?? false else {
+            dispatch_queue.async {
+                completionHandler(nil, nil, nil, self.throwError(path, code: URLError.resourceUnavailable))
+            }
+            return
+        }
+        
+        let url = self.url(of: path)
+        var request = URLRequest(url: url)
+        request.httpMethod = "PROPPATCH"
+        request.set(httpAuthentication: credential, with: credentialType)
+        request.set(contentType: .xml)
+        let body = "<propertyupdate xmlns=\"DAV:\">\n<set><prop>\n<public_url xmlns=\"urn:yandex:disk:meta\">true</public_url>\n</prop></set>\n</propertyupdate>"
+        request.httpBody = body.data(using: .utf8)
+        request.setValue(String(request.httpBody!.count), forHTTPHeaderField: "Content-Length")
+        runDataTask(with: request, completionHandler: { (data, response, error) in
+            var responseError: FileProviderWebDavError?
+            if let code = (response as? HTTPURLResponse)?.statusCode, code >= 300, let rCode = FileProviderHTTPErrorCode(rawValue: code) {
+                responseError = FileProviderWebDavError(code: rCode, path: path, errorDescription: String(data: data ?? Data(), encoding: .utf8), url: url)
+            }
+            if let data = data {
+                let xresponse = DavResponse.parse(xmlResponse: data, baseURL: self.baseURL)
+                if let urlStr = xresponse.first?.prop["public_url"], let url = URL(string: urlStr) {
+                    completionHandler(url, nil, nil, nil)
+                    return
+                }
+            }
+            completionHandler(nil, nil, nil, responseError ?? error)
+        })
+    }
+}
+
 extension WebDAVFileProvider: FileProvider { }
 
 // MARK: WEBDAV XML response implementation
@@ -520,12 +739,9 @@ struct DavResponse {
     
     init? (_ node: AEXMLElement, baseURL: URL?) {
         
-        func removeSlash(_ str: String) -> String {
-            if str.hasPrefix("/") {
-                return str.substring(from: str.index(after: str.startIndex))
-            } else {
-                return str
-            }
+        func standardizePath(_ str: String) -> String {
+            let trimmedStr = str.hasPrefix("/") ? str.substring(from: str.index(after: str.startIndex)) : str
+            return trimmedStr.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlPathAllowed.subtracting(CharacterSet(charactersIn: ":"))) ?? str
         }
         
         // find node names with namespace
@@ -554,7 +770,7 @@ struct DavResponse {
         } else {
             relativePath = hrefAbsolute?.absoluteString.replacingOccurrences(of: baseURL?.absoluteString ?? "", with: "", options: .anchored, range: nil) ?? hrefString
         }
-        let hrefURL = URL(string: removeSlash(relativePath), relativeTo: baseURL) ?? baseURL
+        let hrefURL = URL(string: standardizePath(relativePath), relativeTo: baseURL) ?? baseURL
         
         guard let href = hrefURL?.standardized else { return nil }
         
@@ -616,13 +832,13 @@ struct DavResponse {
 public final class WebDavFileObject: FileObject {
     internal init(_ davResponse: DavResponse) {
         let href = davResponse.href
-        let name = davResponse.prop["displayname"] ?? (davResponse.hrefString.removingPercentEncoding! as NSString).lastPathComponent
+        let name = davResponse.prop["displayname"] ?? davResponse.href.lastPathComponent
         let relativePath = href.relativePath
         let path = relativePath.hasPrefix("/") ? relativePath : ("/" + relativePath)
         super.init(url: href, name: name, path: path)
         self.size = Int64(davResponse.prop["getcontentlength"] ?? "-1") ?? NSURLSessionTransferSizeUnknown
-        self.creationDate = resolve(dateString: davResponse.prop["creationdate"] ?? "")
-        self.modifiedDate = resolve(dateString: davResponse.prop["getlastmodified"] ?? "")
+        self.creationDate = Date(rfcString: davResponse.prop["creationdate"] ?? "")
+        self.modifiedDate = Date(rfcString: davResponse.prop["getlastmodified"] ?? "")
         self.contentType = davResponse.prop["getcontenttype"] ?? "octet/stream"
         self.isHidden = (Int(davResponse.prop["ishidden"] ?? "0") ?? 0) > 0
         self.type = self.contentType == "httpd/unix-directory" ? .directory : .regular
@@ -632,22 +848,54 @@ public final class WebDavFileObject: FileObject {
     /// MIME type of the file.
     open internal(set) var contentType: String {
         get {
-            return allValues[.mimeType] as? String ?? ""
+            return allValues[.mimeTypeKey] as? String ?? ""
         }
         set {
-            allValues[.mimeType] = newValue
+            allValues[.mimeTypeKey] = newValue
         }
     }
     
     /// HTTP E-Tag, can be used to mark changed files.
     open internal(set) var entryTag: String? {
         get {
-            return allValues[.entryTag] as? String
+            return allValues[.entryTagKey] as? String
         }
         set {
-            allValues[.entryTag] = newValue
+            allValues[.entryTagKey] = newValue
         }
     }
+    
+    internal class func resourceKeyToDAVProp(_ key: URLResourceKey) -> String? {
+        switch key {
+        case URLResourceKey.fileSizeKey:
+            return "getcontentlength"
+        case URLResourceKey.creationDateKey:
+            return "creationdate"
+        case URLResourceKey.contentModificationDateKey:
+            return "getlastmodified"
+        case URLResourceKey.fileResourceTypeKey, URLResourceKey.mimeTypeKey:
+            return "getcontenttype"
+        case URLResourceKey.isHiddenKey:
+            return "ishidden"
+        case URLResourceKey.entryTagKey:
+            return "getetag"
+        default:
+            return nil
+        }
+    }
+    
+    internal class func propString(_ keys: [URLResourceKey]) -> String {
+        var propKeys = ""
+        for item in keys {
+            if let prop = WebDavFileObject.resourceKeyToDAVProp(item) {
+                propKeys += "<D:prop><D:\(prop)/></D:prop>"
+            }
+        }
+        if propKeys.isEmpty {
+            propKeys = "<D:allprop/>"
+        }
+        return propKeys
+    }
 }
 
 /// Error returned by WebDAV server when trying to access or do operations on a file or folder.