Added SWAPIProviders that implement the swapi.co WS

2015-10-11 00:44:44 +02:00
11 changed files with 350 additions and 23 deletions
@@ -27,6 +27,12 @@
 		09D796071BC73E8B003C68EB /* StoryboardConstants.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D796061BC73E8B003C68EB /* StoryboardConstants.swift */; settings = {ASSET_TAGS = (); }; };
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 		09D796111BC97809003C68EB /* mainPilot.plist in Resources */ = {isa = PBXBuildFile; fileRef = 09D796101BC97809003C68EB /* mainPilot.plist */; settings = {ASSET_TAGS = (); }; };
+		09D796131BC9A5BC003C68EB /* SWAPIPersonProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D796121BC9A5BC003C68EB /* SWAPIPersonProvider.swift */; settings = {ASSET_TAGS = (); }; };
+		09D796151BC9A5FC003C68EB /* NetworkLayer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D796141BC9A5FC003C68EB /* NetworkLayer.swift */; settings = {ASSET_TAGS = (); }; };
+		09D796171BC9B53D003C68EB /* URLSessionNetworkLayer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D796161BC9B53D003C68EB /* URLSessionNetworkLayer.swift */; settings = {ASSET_TAGS = (); }; };
+		09D796191BC9BA49003C68EB /* DependencyContainers.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D796181BC9BA49003C68EB /* DependencyContainers.swift */; settings = {ASSET_TAGS = (); }; };
+		09D7961B1BC9BE65003C68EB /* SWAPIStarshipProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D7961A1BC9BE65003C68EB /* SWAPIStarshipProvider.swift */; settings = {ASSET_TAGS = (); }; };
+		09D7961D1BC9C62E003C68EB /* SWAPICommon.swift in Sources */ = {isa = PBXBuildFile; fileRef = 09D7961C1BC9C62E003C68EB /* SWAPICommon.swift */; settings = {ASSET_TAGS = (); }; };
 		607FACEC1AFB9204008FA782 /* SWAPIWebServiceTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 607FACEB1AFB9204008FA782 /* SWAPIWebServiceTests.swift */; };
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@@ -56,6 +62,12 @@
 		09D796061BC73E8B003C68EB /* StoryboardConstants.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = StoryboardConstants.swift; sourceTree = "<group>"; };
 		09D7960C1BC7431C003C68EB /* FetchableTrait.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FetchableTrait.swift; sourceTree = "<group>"; };
 		09D796101BC97809003C68EB /* mainPilot.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = mainPilot.plist; sourceTree = "<group>"; };
+		09D796121BC9A5BC003C68EB /* SWAPIPersonProvider.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SWAPIPersonProvider.swift; sourceTree = "<group>"; };
+		09D796141BC9A5FC003C68EB /* NetworkLayer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = NetworkLayer.swift; sourceTree = "<group>"; };
+		09D796161BC9B53D003C68EB /* URLSessionNetworkLayer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = URLSessionNetworkLayer.swift; sourceTree = "<group>"; };
+		09D796181BC9BA49003C68EB /* DependencyContainers.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DependencyContainers.swift; sourceTree = "<group>"; };
+		09D7961A1BC9BE65003C68EB /* SWAPIStarshipProvider.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SWAPIStarshipProvider.swift; sourceTree = "<group>"; };
+		09D7961C1BC9C62E003C68EB /* SWAPICommon.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SWAPICommon.swift; sourceTree = "<group>"; };
 		2FE9C70E965FF88C3F20AC76 /* Pods_DipSampleApp.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_DipSampleApp.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		304AD039660A2C58EB08D985 /* Pods_DipTests.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_DipTests.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		607FACE51AFB9204008FA782 /* DipTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = DipTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -103,9 +115,11 @@
 		0900121A1BC6FECA0079C600 /* Providers */ = {
 			isa = PBXGroup;
 			children = (
+				09D7961C1BC9C62E003C68EB /* SWAPICommon.swift */,
 				090012371BC6FEEA0079C600 /* APIs */,
 				090012381BC6FEFD0079C600 /* PersonProviders */,
 				090012391BC6FF080079C600 /* StarshipProviders */,
+				09D796161BC9B53D003C68EB /* URLSessionNetworkLayer.swift */,
 			);
 			path = Providers;
 			sourceTree = "<group>";
@@ -125,6 +139,7 @@
 			children = (
 				0900121B1BC6FECA0079C600 /* PersonProviderAPI.swift */,
 				0900123C1BC7012A0079C600 /* StarshipProviderAPI.swift */,
+				09D796141BC9A5FC003C68EB /* NetworkLayer.swift */,
 			);
 			name = APIs;
 			sourceTree = "<group>";
@@ -134,6 +149,7 @@
 			children = (
 				0900121C1BC6FECA0079C600 /* DummyPilotProvider.swift */,
 				0900121E1BC6FECA0079C600 /* PlistPersonProvider.swift */,
+				09D796121BC9A5BC003C68EB /* SWAPIPersonProvider.swift */,
 			);
 			name = PersonProviders;
 			sourceTree = "<group>";
@@ -143,6 +159,7 @@
 			children = (
 				090012431BC708A00079C600 /* DummyStarshipProvider.swift */,
 				0900121D1BC6FECA0079C600 /* HardCodedStarshipProvider.swift */,
+				09D7961A1BC9BE65003C68EB /* SWAPIStarshipProvider.swift */,
 			);
 			name = StarshipProviders;
 			sourceTree = "<group>";
@@ -161,6 +178,7 @@
 			children = (
 				0900123A1BC6FF4D0079C600 /* Main.storyboard */,
 				099022611BC123C000E76F43 /* AppDelegate.swift */,
+				09D796181BC9BA49003C68EB /* DependencyContainers.swift */,
 				0900123E1BC704A80079C600 /* Model */,
 				0900121A1BC6FECA0079C600 /* Providers */,
 				090012201BC6FECA0079C600 /* ViewControllers */,
@@ -442,15 +460,19 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				09D796151BC9A5FC003C68EB /* NetworkLayer.swift in Sources */,
 				09D795FF1BC71F5A003C68EB /* PersonListViewController.swift in Sources */,
 				0900122A1BC6FECA0079C600 /* PersonCell.swift in Sources */,
 				09D796011BC722C0003C68EB /* StarshipListViewController.swift in Sources */,
 				0900122C1BC6FECA0079C600 /* PersonProviderAPI.swift in Sources */,
+				09D7961D1BC9C62E003C68EB /* SWAPICommon.swift in Sources */,
 				090012291BC6FECA0079C600 /* BaseCell.swift in Sources */,
 				0900122D1BC6FECA0079C600 /* DummyPilotProvider.swift in Sources */,
 				099022621BC123C000E76F43 /* AppDelegate.swift in Sources */,
+				09D796131BC9A5BC003C68EB /* SWAPIPersonProvider.swift in Sources */,
 				090012421BC7059E0079C600 /* Starship.swift in Sources */,
 				0900123D1BC7012A0079C600 /* StarshipProviderAPI.swift in Sources */,
+				09D7961B1BC9BE65003C68EB /* SWAPIStarshipProvider.swift in Sources */,
 				0900122E1BC6FECA0079C600 /* HardCodedStarshipProvider.swift in Sources */,
 				09D796071BC73E8B003C68EB /* StoryboardConstants.swift in Sources */,
 				09D796031BC72691003C68EB /* StarshipCell.swift in Sources */,
@@ -458,6 +480,8 @@
 				090012441BC708A00079C600 /* DummyStarshipProvider.swift in Sources */,
 				09D7960D1BC7431C003C68EB /* FetchableTrait.swift in Sources */,
 				0900122F1BC6FECA0079C600 /* PlistPersonProvider.swift in Sources */,
+				09D796191BC9BA49003C68EB /* DependencyContainers.swift in Sources */,
+				09D796171BC9B53D003C68EB /* URLSessionNetworkLayer.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -1,30 +1,12 @@
 //
 //  AppDelegate.swift
-//  DipSampleApp
+//  Dip
 //
 //  Created by Olivier Halligon on 04/10/2015.
 //  Copyright © 2015 AliSoftware. All rights reserved.
 //

 import UIKit
-import Dip
-
-let dip: DependencyContainer<Int> = {
-    let dip = DependencyContainer<Int>()
-
-    // 1) Register the PersonProviderAPI singleton, one generic and one specific for a specific personID
-    dip.register(instance: DummyPilotProvider() as PersonProviderAPI)
-    let mainPersonProvider = PlistPersonProvider(plist: "mainPilot")
-    dip.register(0, instance: mainPersonProvider as PersonProviderAPI)
-    
-    // 2) Register the StarshipProviderAPI factories, one generic and one specific for a specific starshipID
-    dip.register() { HardCodedStarshipProvider() as StarshipProviderAPI }
-    let pilotName = mainPersonProvider.people[0].name
-    dip.register(0) { DummyStarshipProvider(pilotName: pilotName) as StarshipProviderAPI }
-
-    return dip
-}()
-

@UIApplicationMain
 class AppDelegate: UIResponder, UIApplicationDelegate {
@@ -0,0 +1,66 @@
+//
+//  DependencyContainers.swift
+//  Dip
+//
+//  Created by Olivier Halligon on 10/10/2015.
+//  Copyright © 2015 AliSoftware. All rights reserved.
+//
+
+import Foundation
+import Dip
+
+
+enum WebService {
+    case PersonWS
+    case StarshipWS
+}
+
+// Dependency Container for WebServices & NetworkLayer
+let wsDependencies: DependencyContainer<WebService> = {
+    let dip = DependencyContainer<WebService>()
+    
+    // Register the NetworkLayer, same for everyone here (but we have the ability to register a different one for a specific WebService if we wanted to)
+    dip.register(instance: URLSessionNetworkLayer(baseURL: "http://swapi.co/api/")! as NetworkLayer)
+    
+    return dip
+}()
+
+
+
+/* Change this to toggle between real and fake data */
+let FAKE_PERSONS = false
+let FAKE_STARSHIPS = false
+
+
+// Dependency Container for Providers
+let providerDependencies: DependencyContainer<Int> = {
+    let dip = DependencyContainer<Int>()
+
+    if FAKE_PERSONS {
+        
+        // 1) Register the PersonProviderAPI singleton, one generic and one specific for a specific personID
+        dip.register(instance: DummyPilotProvider() as PersonProviderAPI)
+        dip.register(0, instance: PlistPersonProvider(plist: "mainPilot") as PersonProviderAPI)
+        
+    } else {
+        
+        // 1) Register the SWAPIPersonProvider (that hits the real swapi.co WebService)
+        dip.register(instance: SWAPIPersonProvider() as PersonProviderAPI)
+
+    }
+    
+    if FAKE_STARSHIPS {
+
+        // 2) Register the StarshipProviderAPI factories, one generic and one specific for a specific starshipID
+        dip.register() { HardCodedStarshipProvider() as StarshipProviderAPI }
+        dip.register(0) { DummyStarshipProvider(pilotName: "Main Pilot") as StarshipProviderAPI }
+        
+    } else {
+        
+        // 2) Register the SWAPIStarshipProvider (that hits the real swapi.co WebService)
+        dip.register(instance: SWAPIStarshipProvider() as StarshipProviderAPI)
+
+    }
+    
+    return dip
+}()
@@ -0,0 +1,32 @@
+//
+//  NetworkLayer.swift
+//  Dip
+//
+//  Created by Olivier Halligon on 10/10/2015.
+//  Copyright © 2015 AliSoftware. All rights reserved.
+//
+
+import Foundation
+
+enum NetworkResponse {
+    case Success(NSData, NSHTTPURLResponse)
+    case Error(NSError)
+    
+    func unwrap() throws -> (NSData, NSHTTPURLResponse) {
+        switch self {
+        case Success(let data, let response):
+            return (data, response)
+        case Error(let error):
+            throw error
+        }
+    }
+    
+    func json() throws -> AnyObject {
+        let (data, _) = try self.unwrap()
+        return try NSJSONSerialization.JSONObjectWithData(data, options: [])
+    }
+}
+
+protocol NetworkLayer {
+    func request(path: String, completion: NetworkResponse -> Void)
+}
@@ -0,0 +1,19 @@
+//
+//  SWAPICommon.swift
+//  Dip
+//
+//  Created by Olivier Halligon on 11/10/2015.
+//  Copyright © 2015 AliSoftware. All rights reserved.
+//
+
+import Foundation
+
+enum SWAPIError: ErrorType {
+    case InvalidJSON
+}
+
+func idFromURLString(urlString: String) -> Int? {
+    let url = NSURL(string: urlString)
+    let idString = url.flatMap { $0.lastPathComponent }
+    return idString.flatMap { Int($0) }
+}
@@ -0,0 +1,64 @@
+//
+//  SWAPIPersonProvider.swift
+//  Dip
+//
+//  Created by Olivier Halligon on 10/10/2015.
+//  Copyright © 2015 AliSoftware. All rights reserved.
+//
+
+import Foundation
+
+struct SWAPIPersonProvider : PersonProviderAPI {
+    let ws = wsDependencies.resolve(.PersonWS) as NetworkLayer
+    
+    func fetchIDs(completion: [Int] -> Void) {
+        ws.request("people") { response in
+            do {
+                let dict = try response.json()
+                guard let results = dict["results"] as? [NSDictionary] else { throw SWAPIError.InvalidJSON }
+                
+                // Extract URLs (flatten to ignore invalid ones)
+                let urlStrings = results.flatMap({ $0["url"] as? String })
+                let ids = urlStrings.flatMap(idFromURLString)
+                
+                completion(ids)
+            }
+            catch {
+                completion([])
+            }
+        }
+    }
+    
+    func fetch(id: Int, completion: Person? -> Void) {
+        ws.request("people/\(id)") { response in
+            do {
+                let json = try response.json()
+                guard let dict = json as? NSDictionary,
+                    let name = dict["name"] as? String,
+                    let heightStr = dict["height"] as? String, height = Int(heightStr),
+                    let massStr = dict["mass"] as? String, mass = Int(massStr),
+                    let hairColor = dict["hair_color"] as? String,
+                    let eyeColor = dict["eye_color"] as? String,
+                    let gender = dict["gender"] as? String,
+                    let starshipURLStrings = dict["starships"] as? [String]
+                    else {
+                        throw SWAPIError.InvalidJSON
+                }
+                
+                let person = Person(
+                    name: name,
+                    height: height,
+                    mass: mass,
+                    hairColor: hairColor,
+                    eyeColor: eyeColor,
+                    gender: Gender(rawValue: gender),
+                    starshipIDs: starshipURLStrings.flatMap(idFromURLString)
+                )
+                completion(person)
+            }
+            catch {
+                completion(nil)
+            }
+        }
+    }
+}
@@ -0,0 +1,62 @@
+//
+//  SWAPIStarshipProvider.swift
+//  Dip
+//
+//  Created by Olivier Halligon on 10/10/2015.
+//  Copyright © 2015 AliSoftware. All rights reserved.
+//
+
+import Foundation
+
+struct SWAPIStarshipProvider : StarshipProviderAPI {
+    let ws = wsDependencies.resolve(.StarshipWS) as NetworkLayer
+    
+    func fetchIDs(completion: [Int] -> Void) {
+        ws.request("starships") { response in
+            do {
+                let dict = try response.json()
+                guard let results = dict["results"] as? [NSDictionary] else { throw SWAPIError.InvalidJSON }
+                
+                // Extract URLs (flatten to ignore invalid ones)
+                let urlStrings = results.flatMap({ $0["url"] as? String })
+                let ids = urlStrings.flatMap(idFromURLString)
+                
+                completion(ids)
+            }
+            catch {
+                completion([])
+            }
+        }
+    }
+    
+    func fetch(id: Int, completion: Starship? -> Void) {
+        ws.request("starships/\(id)") { response in
+            do {
+                let json = try response.json()
+                guard let dict = json as? NSDictionary,
+                    let name = dict["name"] as? String,
+                    let model = dict["model"] as? String,
+                    let manufacturer = dict["manufacturer"] as? String,
+                    let crewStr = dict["crew"] as? String, crew = Int(crewStr),
+                    let passengersStr = dict["passengers"] as? String, passengers = Int(passengersStr),
+                    let pilotIDStrings = dict["pilots"] as? [String]
+                    else {
+                        throw SWAPIError.InvalidJSON
+                }
+                
+                let ship = Starship(
+                    name: name,
+                    model: model,
+                    manufacturer: manufacturer,
+                    crew: crew,
+                    passengers: passengers,
+                    pilotIDs: pilotIDStrings.flatMap(idFromURLString)
+                )
+                completion(ship)
+            }
+            catch {
+                completion(nil)
+            }
+        }
+    }
+}
@@ -0,0 +1,44 @@
+//
+//  URLSessionNetworkLayer.swift
+//  Dip
+//
+//  Created by Olivier Halligon on 10/10/2015.
+//  Copyright © 2015 AliSoftware. All rights reserved.
+//
+
+import Foundation
+
+struct URLSessionNetworkLayer : NetworkLayer {
+    let baseURL: NSURL
+    let session: NSURLSession
+    let responseQueue: dispatch_queue_t
+    
+    init?(baseURL: String, session: NSURLSession = .sharedSession(), responseQueue: dispatch_queue_t = dispatch_get_main_queue()) {
+        guard let url = NSURL(string: baseURL) else { return nil }
+        self.init(baseURL: url, session: session)
+    }
+    
+    init(baseURL: NSURL, session: NSURLSession = .sharedSession(), responseQueue: dispatch_queue_t = dispatch_get_main_queue()) {
+        self.baseURL = baseURL
+        self.session = session
+        self.responseQueue = responseQueue
+    }
+    
+    func request(path: String, completion: NetworkResponse -> Void) {
+        let url = self.baseURL.URLByAppendingPathComponent(path)
+        let task = session.dataTaskWithURL(url) { data, response, error in
+            if let data = data, let response = response as? NSHTTPURLResponse {
+                dispatch_async(self.responseQueue) {
+                    completion(NetworkResponse.Success(data, response))
+                }
+            }
+            else {
+                let err = error ?? NSError(domain: NSURLErrorDomain, code: NSURLError.Unknown.rawValue, userInfo: nil)
+                dispatch_async(self.responseQueue) {
+                    completion(NetworkResponse.Error(err))
+                }
+            }
+        }
+        task.resume()
+    }
+}
@@ -16,6 +16,7 @@ protocol FetchableTrait: class {
    
    var fetchIDs: ([Int] -> Void) -> Void { get }
    var fetchOne: (Int, ObjectType? -> Void) -> Void { get }
+    var fetchProgress: (current: Int, total: Int?) { get set }
 }

 extension FetchableTrait {
@@ -24,6 +25,7 @@ extension FetchableTrait {
        let batch = self.batchRequestID
        
        objects?.removeAll()
+        fetchProgress = (0,objectIDs.count)
        for objectID in objectIDs {
            fetchOne(objectID) { (object: ObjectType?) in
                // Exit if we failed to retrive an object for this ID, or if the request
@@ -32,6 +34,7 @@ extension FetchableTrait {

                if self.objects == nil { self.objects = [] }
                self.objects?.append(object)
+                self.fetchProgress = (self.objects?.count ?? 0, objectIDs.count)
                self.tableView?.reloadData()
            }
        }
@@ -40,10 +43,29 @@ extension FetchableTrait {
    func fetchAllObjects() {
        self.batchRequestID += 1
        let batch = self.batchRequestID
-        
+        fetchProgress = (0, nil)
        fetchIDs() { objectIDs in
            guard batch == self.batchRequestID else { return }
            self.fetchObjects(objectIDs)
        }
    }
+    
+    func displayProgressInNavBar(navigationItem: UINavigationItem) {
+        let text: String
+        if let total = fetchProgress.total {
+            if fetchProgress.current == fetchProgress.total {
+                text = "Done."
+            } else {
+                text = "Loading \(fetchProgress.current) / \(total)…"
+            }
+        } else {
+            text = "Loading IDs…"
+        }
+        let label = UILabel(frame: CGRect(x: 0, y: 0, width: 0, height: 0))
+        label.text = text
+        label.textColor = .grayColor()
+        label.font = .systemFontOfSize(12)
+        label.sizeToFit()
+        navigationItem.rightBarButtonItem = UIBarButtonItem(customView: label)
+    }
 }
@@ -12,11 +12,17 @@ class PersonListViewController: UITableViewController, FetchableTrait {
    var objects: [Person]?
    var batchRequestID = 0
        
-    lazy var fetchIDs: ([Int] -> Void) -> Void = (dip.resolve() as PersonProviderAPI).fetchIDs
+    lazy var fetchIDs: ([Int] -> Void) -> Void = (providerDependencies.resolve() as PersonProviderAPI).fetchIDs
    lazy var fetchOne: (Int, Person? -> Void) -> Void = { personID, completion in
-        let provider = dip.resolve(personID) as PersonProviderAPI
+        let provider = providerDependencies.resolve(personID) as PersonProviderAPI
        return provider.fetch(personID, completion: completion)
    }
+    
+    var fetchProgress: (current: Int, total: Int?) = (0, nil) {
+        didSet {
+            displayProgressInNavBar(self.navigationItem)
+        }
+    }

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        guard
@@ -12,13 +12,19 @@ class StarshipListViewController : UITableViewController, FetchableTrait {
    var objects: [Starship]?
    var batchRequestID = 0
    
-    var provider: (Int? -> StarshipProviderAPI) = { dip.resolve($0) }
+    var provider: (Int? -> StarshipProviderAPI) = { providerDependencies.resolve($0) }

    lazy var fetchIDs: ([Int] -> Void) -> Void = self.provider(nil).fetchIDs
    lazy var fetchOne: (Int, Starship? -> Void) -> Void = { shipID, completion in
        self.provider(shipID).fetch(shipID, completion: completion)
    }
    
+    var fetchProgress: (current: Int, total: Int?) = (0, nil) {
+        didSet {
+            displayProgressInNavBar(self.navigationItem)
+        }
+    }
+    
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        guard
            let id = segue.identifier, segueID = UIStoryboard.Segue.Main(rawValue: id)