Correct EventSource error handler.

README.markdown

@@ -7,6 +7,11 @@ rather makes it easy to handle WebSocket connections within an existing
 [Node](http://nodejs.org/) application. It does not provide any abstraction
 other than the standard [WebSocket API](http://dev.w3.org/html5/websockets/).
 
+It also provides an abstraction for handling [EventSource](http://dev.w3.org/html5/eventsource/)
+connections, which are one-way connections that allow the server to push data to
+the client. They are based on streaming HTTP responses and can be easier to
+access via proxies than WebSockets.
+
 The server-side socket can process [draft-75](http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-75),
 [draft-76](http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76),
 [hybi-07](http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-07)
@@ -15,7 +20,7 @@ supports both `text` and `binary` messages, and transparently handles `ping`,
 `pong`, `close` and fragmented messages.
 
 
-## Accepting WebSocket connections in Node
+## Handling WebSocket connections in Node
 
 You can handle WebSockets on the server side by listening for HTTP Upgrade
 requests, and creating a new socket for the request. This socket object exposes
@@ -49,8 +54,7 @@ server.listen(8000);
 
 The client supports both the plain-text `ws` protocol and the encrypted `wss`
 protocol, and has exactly the same interface as a socket you would use in a web
-browser. On the wire it identifies itself as hybi-13, though it's compatible
-with servers speaking later versions of the protocol.
+browser. On the wire it identifies itself as hybi-13.
 
 ```js
 var WebSocket = require('faye-websocket'),
@@ -115,15 +119,86 @@ messages.
   sends a text or binary message over the connection to the other peer.
 * <b><tt>close(code, reason)</tt></b> closes the connection, sending the given
   status code and reason text, both of which are optional.
-* <b><tt>protocol</tt></b> is a string or `null` identifying the subprotocol the
-  socket is using.
+* <b><tt>protocol</tt></b> is a string (which may be empty) identifying the
+  subprotocol the socket is using.
+
+
+## Handling EventSource connections in Node
+
+EventSource connections provide a very similar interface, although because they
+only allow the server to send data to the client, there is no `onmessage` API.
+EventSource allows the server to push text messages to the client, where each
+message has an optional event-type and ID.
+
+```js
+var WebSocket   = require('faye-websocket'),
+    EventSource = WebSocket.EventSource,
+    http        = require('http');
+
+var server = http.createServer();
+
+server.addListener('request', function(request, response) {
+  if (EventSource.isEventSource(request)) {
+    var es = new EventSource(request, response);
+    console.log('open', es.url, es.lastEventId);
+    
+    // Periodically send messages
+    var loop = setInterval(function() { es.send('Hello') }, 1000);
+    
+    es.onclose = function() {
+      clearInterval(loop);
+      es = null;
+    };
+  
+  } else {
+    // Normal HTTP request
+    response.writeHead(200, {'Content-Type': 'text/plain'});
+    response.write('Hello');
+    response.end();
+  }
+});
+
+server.listen(8000);
+```
+
+The `send` method takes two optional parameters, `event` and `id`. The default
+event-type is `'message'` with no ID. For example, to send a `notification`
+event with ID `99`:
+
+```js
+es.send('Breaking News!', {event: 'notification', id: '99'});
+```
+
+The `EventSource` object exposes the following properties:
+
+* <b><tt>url</tt></b> is a string containing the URL the client used to create
+  the EventSource.
+* <b><tt>lastEventId</tt></b> is a string containing the last event ID
+  received by the client. You can use this when the client reconnects after a
+  dropped connection to determine which messages need resending.
+
+When you initialize an EventSource with ` new EventSource()`, you can pass
+configuration options after the `response` parameter. Available options are:
+
+* <b><tt>retry</tt></b> is a number that tells the client how long (in seconds)
+  it should wait after a dropped connection before attempting to reconnect.
+* <b><tt>ping</tt></b> is a number that tells the server how often (in seconds)
+  to send 'ping' packets to the client to keep the connection open, to defeat
+  timeouts set by proxies. The client will ignore these messages.
+
+For example, this creates a connection that pings every 15 seconds and is
+retryable every 10 seconds if the connection is broken:
+
+```js
+var es = new EventSource(request, response, {ping: 15, retry: 10});
+```
 
 
 ## License
 
 (The MIT License)
 
-Copyright (c) 2009-2011 James Coglan
+Copyright (c) 2009-2012 James Coglan
 
 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

examples/server.js

@@ -6,6 +6,46 @@ var WebSocket = require('../lib/faye/websocket'),
 var port   = process.argv[2] || 7000,
     secure = process.argv[3] === 'ssl';
 
+var upgradeHandler = function(request, socket, head) {
+  var ws = new WebSocket(request, socket, head, ['irc', 'xmpp']);
+  console.log('open', ws.url, ws.version, ws.protocol);
+  
+  ws.onmessage = function(event) {
+    ws.send(event.data);
+  };
+  
+  ws.onclose = function(event) {
+    console.log('close', event.code, event.reason);
+    ws = null;
+  };
+};
+
+var requestHandler = function(request, response) {
+  if (!WebSocket.EventSource.isEventSource(request))
+    return staticHandler(request, response);
+  
+  var es   = new WebSocket.EventSource(request, response),
+      time = parseInt(es.lastEventId, 10) || 0;
+  
+  console.log('open', es.url, es.lastEventId);
+  
+  var loop = setInterval(function() {
+    time += 1;
+    es.send('Time: ' + time);
+    setTimeout(function() {
+      if (es) es.send('Update!!', {event: 'update', id: time});
+    }, 1000);
+  }, 2000);
+  
+  es.send('Welcome!\n\nThis is an EventSource server.');
+  
+  es.onclose = function() {
+    clearInterval(loop);
+    console.log('close', es.url);
+    es = null;
+  };
+};
+
 var staticHandler = function(request, response) {
   var path = request.url;
   
@@ -22,20 +62,9 @@ var server = secure
                key:  fs.readFileSync(__dirname + '/../spec/server.key'),
                cert: fs.readFileSync(__dirname + '/../spec/server.crt')
              })
-           : http.createServer(staticHandler);
-
-server.addListener('upgrade', function(request, socket, head) {
-  var ws = new WebSocket(request, socket, head, ['irc', 'xmpp']);
-  console.log('open', ws.url, ws.version, ws.protocol);
-  
-  ws.onmessage = function(event) {
-    ws.send(event.data);
-  };
-  
-  ws.onclose = function(event) {
-    console.log('close', event.code, event.reason);
-    ws = null;
-  };
-});
+           : http.createServer();
 
+server.addListener('request', requestHandler);
+server.addListener('upgrade', upgradeHandler);
 server.listen(port);
+

examples/sse.html

@@ -0,0 +1,39 @@
+<!doctype html>
+<html>
+  <head>
+    <meta http-equiv="Content-type" content="text/html; charset=utf-8">
+    <title>EventSource test</title>
+  </head>
+  <body>
+    
+    <h1>EventSource test</h1>
+    <ul></ul>
+    
+    <script type="text/javascript">
+      var logger = document.getElementsByTagName('ul')[0],
+          socket = new EventSource('/');
+      
+      var log = function(text) {
+        logger.innerHTML += '<li>' + text + '</li>';
+      };
+      
+      socket.onopen = function() {
+        log('OPEN');
+      };
+      
+      socket.onmessage = function(event) {
+        log('MESSAGE: ' + event.data);
+      };
+      
+      socket.addEventListener('update', function(event) {
+        log('UPDATE(' + event.lastEventId + '): ' + event.data);
+      });
+      
+      socket.onerror = function(event) {
+        log('ERROR: ' + event.message);
+      };
+    </script>
+    
+  </body>
+</html>
+

examples/ws.html

@@ -16,22 +16,26 @@
           socket = new Socket('ws://' + location.hostname + ':' + location.port + '/', protos),
           index  = 0;
       
-      socket.onopen = function() {
-        logger.innerHTML += '<li>OPEN: ' + socket.protocol + '</li>';
+      var log = function(text) {
+        logger.innerHTML += '<li>' + text + '</li>';
+      };
+      
+      socket.addEventListener('open', function() {
+        log('OPEN: ' + socket.protocol);
         socket.send('Hello, world');
-      };
-      
-      socket.onerror = function(event) {
-        logger.innerHTML += '<li>ERROR: ' + error.message + '</li>';
-      };
-      
-      socket.addEventListener('message', function(event) {
-        logger.innerHTML += '<li>MESSAGE: ' + event.data + '</li>';
-        setTimeout(function() { socket.send(++index + ' ' + event.data) }, 2000);
       });
       
+      socket.onerror = function(event) {
+        log('ERROR: ' + event.message);
+      };
+      
+      socket.onmessage = function(event) {
+        log('MESSAGE: ' + event.data);
+        setTimeout(function() { socket.send(++index + ' ' + event.data) }, 2000);
+      };
+      
       socket.onclose = function(event) {
-        logger.innerHTML += '<li>CLOSE: ' + event.code + ', ' + event.reason + '</li>';
+        log('CLOSE: ' + event.code + ', ' + event.reason);
       };
     </script>
     

lib/faye/eventsource.js

@@ -0,0 +1,92 @@
+var API   = require('./websocket/api'),
+    Event = require('./websocket/api/event');
+
+var isSecureConnection = function(request) {
+  if (request.headers['x-forwarded-proto']) {
+    return request.headers['x-forwarded-proto'] === 'https';
+  } else {
+    return (request.connection && request.connection.authorized !== undefined) ||
+           (request.socket && request.socket.secure);
+  }
+};
+
+var EventSource = function(request, response, options) {
+  options = options || {};
+  
+  this._request  = request;
+  this._response = response;
+  this._stream   = response.socket;
+  this._ping     = options.ping  || this.DEFAULT_PING;
+  this._retry    = options.retry || this.DEFAULT_RETRY;
+  
+  var scheme = isSecureConnection(request) ? 'https:' : 'http:';
+  this.url = scheme + '//' + request.headers.host + request.url;
+  
+  this.lastEventId = request.headers['last-event-id'] || '';
+  this.readyState  = API.OPEN;
+  
+  var event = new Event('open');
+  event.initEvent('open', false, false);
+  this.dispatchEvent(event);
+  
+  var self = this;
+  this._pingLoop = setInterval(function() {
+    try { this._stream.write(':\r\n\r\n') } catch (e) {}
+  }, this._ping * 1000);
+  
+  ['close', 'end', 'error'].forEach(function(event) {
+    self._stream.addListener(event, function() { self.close() });
+  });
+  
+  var handshake = 'HTTP/1.1 200 OK\r\n' +
+                  'Content-Type: text/event-stream\r\n' +
+                  'Cache-Control: no-cache, no-store\r\n' +
+                  '\r\n\r\n' +
+                  'retry: ' + Math.floor(this._retry * 1000) + '\r\n\r\n';
+  
+  try {
+    this._stream.write(handshake, 'utf8');
+  } catch (e) {}
+};
+
+EventSource.isEventSource = function(request) {
+  var accept = (request.headers.accept || '').split(/\s*,\s*/);
+  return accept.indexOf('text/event-stream') >= 0;
+};
+
+var instance = {
+  DEFAULT_PING:   10,
+  DEFAULT_RETRY:  5,
+  
+  send: function(message, options) {
+    message = message.replace(/(\r\n|\r|\n)/g, '$1data: ');
+    options = options || {};
+    
+    var frame = '';
+    if (options.event) frame += 'event: ' + options.event + '\r\n';
+    if (options.id)    frame += 'id: '    + options.id    + '\r\n';
+    frame += 'data: ' + message + '\r\n\r\n';
+    
+    try {
+      this._stream.write(frame, 'utf8');
+    } catch (e) {}
+  },
+  
+  close: function() {
+    if (this.readyState === API.CLOSING || this.readyState === API.CLOSED)
+      return;
+    
+    this.readyState = API.CLOSED;
+    clearInterval(this._pingLoop);
+    this._response.end();
+    
+    var event = new Event('close');
+    event.initEvent('close', false, false);
+    this.dispatchEvent(event);
+  }
+};
+
+for (var key in API) EventSource.prototype[key] = API[key];
+for (var key in instance) EventSource.prototype[key] = instance[key];
+module.exports = EventSource;
+

lib/faye/websocket.js

@@ -10,7 +10,8 @@
 var Draft75Parser = require('./websocket/draft75_parser'),
     Draft76Parser = require('./websocket/draft76_parser'),
     HybiParser    = require('./websocket/hybi_parser'),
-    API           = require('./websocket/api');
+    API           = require('./websocket/api'),
+    Event         = require('./websocket/api/event');
 
 var getParser = function(request) {
   var headers = request.headers;
@@ -35,7 +36,7 @@ var WebSocket = function(request, socket, head, supportedProtos) {
   this._stream = request.socket;
   
   var scheme = isSecureConnection(request) ? 'wss:' : 'ws:';
-  this.url = scheme + '//' + request.headers.host + request.url;    
+  this.url = scheme + '//' + request.headers.host + request.url;
   this.readyState = API.CONNECTING;
   this.bufferedAmount = 0;
   
@@ -49,7 +50,7 @@ var WebSocket = function(request, socket, head, supportedProtos) {
   this.readyState = API.OPEN;
   this.version = this._parser.getVersion();
   
-  var event = new API.Event('open');
+  var event = new Event('open');
   event.initEvent('open', false, false);
   this.dispatchEvent(event);
   
@@ -65,9 +66,10 @@ var WebSocket = function(request, socket, head, supportedProtos) {
   });
 };
 
-var API = require('./websocket/api');
 for (var key in API) WebSocket.prototype[key] = API[key];
 
-WebSocket.Client = require('./websocket/client');
-module.exports   = WebSocket;
+WebSocket.WebSocket   = WebSocket;
+WebSocket.Client      = require('./websocket/client');
+WebSocket.EventSource = require('./eventsource');
+module.exports        = WebSocket;
 

lib/faye/websocket/api.js

@@ -1,18 +1,15 @@
+var EventTarget = require('./api/event_target'),
+    Event       = require('./api/event');
+
 var API = {
   CONNECTING:   0,
   OPEN:         1,
   CLOSING:      2,
   CLOSED:       3,
   
-  onopen:     null,
-  onmessage:  null,
-  onerror:    null,
-  onclose:    null,
-  protocol:   null,
-  
   receive: function(data) {
     if (this.readyState !== API.OPEN) return false;
-    var event = new API.Event('message');
+    var event = new Event('message');
     event.initEvent('message', false, false);
     event.data = data;
     this.dispatchEvent(event);
@@ -38,7 +35,7 @@ var API = {
     var close = function() {
       this.readyState = API.CLOSED;
       this._stream.end();
-      var event = new API.Event('close', {code: code || 1000, reason: reason || ''});
+      var event = new Event('close', {code: code || 1000, reason: reason || ''});
       event.initEvent('close', false, false);
       this.dispatchEvent(event);
     };
@@ -50,66 +47,10 @@ var API = {
       if (this._parser.close) this._parser.close(code, reason);
       close.call(this);
     }
-  },
-  
-  addEventListener: function(eventType, listener, useCapture) {
-    this._listeners = this._listeners || {};
-    var list = this._listeners[eventType] = this._listeners[eventType] || [];
-    list.push(listener);
-  },
-  
-  removeEventListener: function(eventType, listener, useCapture) {
-    if (!this._listeners || !this._listeners[eventType]) return;
-    
-    if (!listener) {
-      delete this._listeners[eventType];
-      return;
-    }
-    var list = this._listeners[eventType],
-        i    = list.length;
-    
-    while (i--) {
-      if (listener !== list[i]) continue;
-      list.splice(i,1);
-    }
-  },
-  
-  dispatchEvent: function(event) {
-    event.target = event.currentTarget = this;
-    event.eventPhase = API.Event.AT_TARGET;
-    
-    if (this['on' + event.type])
-      this['on' + event.type](event);
-    
-    if (!this._listeners || !this._listeners[event.type]) return;
-    
-    this._listeners[event.type].forEach(function(listener) {
-      listener(event);
-    }, this);
   }
 };
 
-
-var Event = function(eventType, options) {
-  this.type = eventType;
-  for (var key in options)
-    this[key] = options[key];
-};
-    
-Event.prototype.initEvent = function(eventType, canBubble, cancelable) {
-  this.type       = eventType;
-  this.bubbles    = canBubble;
-  this.cancelable = cancelable;
-};
-
-Event.prototype.stopPropagation = function() {};
-Event.prototype.preventDefault  = function() {};
-    
-Event.CAPTURING_PHASE = 1;
-Event.AT_TARGET       = 2;
-Event.BUBBLING_PHASE  = 3;
-
-API.Event = Event;
+for (var key in EventTarget) API[key] = EventTarget[key];
 
 module.exports = API;
 

lib/faye/websocket/api/event.js

@@ -0,0 +1,21 @@
+var Event = function(eventType, options) {
+  this.type = eventType;
+  for (var key in options)
+    this[key] = options[key];
+};
+    
+Event.prototype.initEvent = function(eventType, canBubble, cancelable) {
+  this.type       = eventType;
+  this.bubbles    = canBubble;
+  this.cancelable = cancelable;
+};
+
+Event.prototype.stopPropagation = function() {};
+Event.prototype.preventDefault  = function() {};
+    
+Event.CAPTURING_PHASE = 1;
+Event.AT_TARGET       = 2;
+Event.BUBBLING_PHASE  = 3;
+
+module.exports = Event;
+

lib/faye/websocket/api/event_target.js

@@ -0,0 +1,47 @@
+var Event = require('./event');
+
+var EventTarget = {
+  onopen:     null,
+  onmessage:  null,
+  onerror:    null,
+  onclose:    null,
+  
+  addEventListener: function(eventType, listener, useCapture) {
+    this._listeners = this._listeners || {};
+    var list = this._listeners[eventType] = this._listeners[eventType] || [];
+    list.push(listener);
+  },
+  
+  removeEventListener: function(eventType, listener, useCapture) {
+    if (!this._listeners || !this._listeners[eventType]) return;
+    
+    if (!listener) {
+      delete this._listeners[eventType];
+      return;
+    }
+    var list = this._listeners[eventType],
+        i    = list.length;
+    
+    while (i--) {
+      if (listener !== list[i]) continue;
+      list.splice(i,1);
+    }
+  },
+  
+  dispatchEvent: function(event) {
+    event.target = event.currentTarget = this;
+    event.eventPhase = Event.AT_TARGET;
+    
+    if (this['on' + event.type])
+      this['on' + event.type](event);
+    
+    if (!this._listeners || !this._listeners[event.type]) return;
+    
+    this._listeners[event.type].forEach(function(listener) {
+      listener(event);
+    }, this);
+  }
+};
+
+module.exports = EventTarget;
+

lib/faye/websocket/client.js

@@ -1,8 +1,9 @@
-var API = require('./api'),
-    net = require('net'),
+var net = require('net'),
     tls = require('tls');
 
-var HybiParser = require('./hybi_parser');
+var HybiParser = require('./hybi_parser'),
+    API        = require('./api'),
+    Event      = require('./api/event');
 
 var Client = function(url, protocols) {
   this.url  = url;
@@ -54,7 +55,7 @@ Client.prototype._onData = function(data) {
       if (this._handshake.isValid()) {
         this.protocol = this._handshake.protocol || '';
         this.readyState = API.OPEN;
-        var event = new API.Event('open');
+        var event = new Event('open');
         event.initEvent('open', false, false);
         this.dispatchEvent(event);
         
@@ -62,7 +63,7 @@ Client.prototype._onData = function(data) {
         
       } else {
         this.readyState = API.CLOSED;
-        var event = new API.Event('close', {code: 1006, reason: ''});
+        var event = new Event('close', {code: 1006, reason: ''});
         event.initEvent('close', false, false);
         this.dispatchEvent(event);
       }

package.json

@@ -1,6 +1,6 @@
 { "name"            : "faye-websocket"
 , "description"     : "Standards-compliant WebSocket server and client"
-, "homepage"        : "http://github.com/jcoglan/faye-websocket-node"
+, "homepage"        : "http://github.com/faye/faye-websocket-node"
 , "author"          : "James Coglan <jcoglan@gmail.com> (http://jcoglan.com/)"
 , "keywords"        : ["websocket"]
 
@@ -9,7 +9,7 @@
 , "main"            : "./lib/faye/websocket"
 , "devDependencies" : {"jsclass": ""}
 
-, "bugs"            : "http://github.com/jcoglan/faye-websocket-node/issues"
+, "bugs"            : "http://github.com/faye/faye-websocket-node/issues"
 
 , "licenses"        : [ { "type"    : "MIT"
                         , "url"     : "http://www.opensource.org/licenses/mit-license.php"
@@ -17,7 +17,7 @@
                       ]
 
 , "repositories"    : [ { "type"    : "git"
-                        , "url"     : "git://github.com/jcoglan/faye-websocket-node.git"
+                        , "url"     : "git://github.com/faye/faye-websocket-node.git"
                         }
                       ]
 }