383 lines
		
	
	
		
			13 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
		
		
			
		
	
	
			383 lines
		
	
	
		
			13 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
|  | // MIT License:
 | ||
|  | //
 | ||
|  | // Copyright (c) 2010-2012, Joe Walnes
 | ||
|  | //
 | ||
|  | // 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.
 | ||
|  | 
 | ||
|  | /** | ||
|  |  * This behaves like a WebSocket in every way, except if it fails to connect, | ||
|  |  * or it gets disconnected, it will repeatedly poll until it successfully connects | ||
|  |  * again. | ||
|  |  * | ||
|  |  * It is API compatible, so when you have: | ||
|  |  *   ws = new WebSocket('ws://....'); | ||
|  |  * you can replace with: | ||
|  |  *   ws = new ReconnectingWebSocket('ws://....'); | ||
|  |  * | ||
|  |  * The event stream will typically look like: | ||
|  |  *  onconnecting | ||
|  |  *  onopen | ||
|  |  *  onmessage | ||
|  |  *  onmessage | ||
|  |  *  onclose // lost connection
 | ||
|  |  *  onconnecting | ||
|  |  *  onopen  // sometime later...
 | ||
|  |  *  onmessage | ||
|  |  *  onmessage | ||
|  |  *  etc... | ||
|  |  * | ||
|  |  * It is API compatible with the standard WebSocket API, apart from the following members: | ||
|  |  * | ||
|  |  * - `bufferedAmount` | ||
|  |  * - `extensions` | ||
|  |  * - `binaryType` | ||
|  |  * | ||
|  |  * Latest version: https://github.com/joewalnes/reconnecting-websocket/
 | ||
|  |  * - Joe Walnes | ||
|  |  * | ||
|  |  * Syntax | ||
|  |  * ====== | ||
|  |  * var socket = new ReconnectingWebSocket(url, protocols, options); | ||
|  |  * | ||
|  |  * Parameters | ||
|  |  * ========== | ||
|  |  * url - The url you are connecting to. | ||
|  |  * protocols - Optional string or array of protocols. | ||
|  |  * options - See below | ||
|  |  * | ||
|  |  * Options | ||
|  |  * ======= | ||
|  |  * Options can either be passed upon instantiation or set after instantiation: | ||
|  |  * | ||
|  |  * var socket = new ReconnectingWebSocket(url, null, { debug: true, reconnectInterval: 4000 }); | ||
|  |  * | ||
|  |  * or | ||
|  |  * | ||
|  |  * var socket = new ReconnectingWebSocket(url); | ||
|  |  * socket.debug = true; | ||
|  |  * socket.reconnectInterval = 4000; | ||
|  |  * | ||
|  |  * debug | ||
|  |  * - Whether this instance should log debug messages. Accepts true or false. Default: false. | ||
|  |  * | ||
|  |  * automaticOpen | ||
|  |  * - Whether or not the websocket should attempt to connect immediately upon instantiation. The socket can be manually opened or closed at any time using ws.open() and ws.close(). | ||
|  |  * | ||
|  |  * reconnectInterval | ||
|  |  * - The number of milliseconds to delay before attempting to reconnect. Accepts integer. Default: 1000. | ||
|  |  * | ||
|  |  * maxReconnectInterval | ||
|  |  * - The maximum number of milliseconds to delay a reconnection attempt. Accepts integer. Default: 30000. | ||
|  |  * | ||
|  |  * reconnectDecay | ||
|  |  * - The rate of increase of the reconnect delay. Allows reconnect attempts to back off when problems persist. Accepts integer or float. Default: 1.5. | ||
|  |  * | ||
|  |  * timeoutInterval | ||
|  |  * - The maximum time in milliseconds to wait for a connection to succeed before closing and retrying. Accepts integer. Default: 2000. | ||
|  |  * | ||
|  |  */ | ||
|  | (function(global, factory) { | ||
|  |   if (typeof define === 'function' && define.amd) { | ||
|  |     define([], factory) | ||
|  |   } else if (typeof module !== 'undefined' && module.exports) { | ||
|  |     module.exports = factory() | ||
|  |   } else { | ||
|  |     global.ReconnectingWebSocket = factory() | ||
|  |   } | ||
|  | })(this, function() { | ||
|  | 
 | ||
|  |   if (!('WebSocket' in window)) { | ||
|  |     return | ||
|  |   } | ||
|  | 
 | ||
|  |   function ReconnectingWebSocket(url, protocols, options) { | ||
|  | 
 | ||
|  |     // Default settings
 | ||
|  |     var settings = { | ||
|  | 
 | ||
|  |       /** Whether this instance should log debug messages. */ | ||
|  |       debug: false, | ||
|  | 
 | ||
|  |       /** Whether or not the websocket should attempt to connect immediately upon instantiation. */ | ||
|  |       automaticOpen: true, | ||
|  | 
 | ||
|  |       /** The number of milliseconds to delay before attempting to reconnect. */ | ||
|  |       reconnectInterval: 1000, | ||
|  |       /** The maximum number of milliseconds to delay a reconnection attempt. */ | ||
|  |       maxReconnectInterval: 30000, | ||
|  |       /** The rate of increase of the reconnect delay. Allows reconnect attempts to back off when problems persist. */ | ||
|  |       reconnectDecay: 1.5, | ||
|  | 
 | ||
|  |       /** The maximum time in milliseconds to wait for a connection to succeed before closing and retrying. */ | ||
|  |       timeoutInterval: 2000, | ||
|  | 
 | ||
|  |       /** The maximum number of reconnection attempts to make. Unlimited if null. */ | ||
|  |       maxReconnectAttempts: null, | ||
|  | 
 | ||
|  |       /** The binary type, possible values 'blob' or 'arraybuffer', default 'blob'. */ | ||
|  |       binaryType: 'blob' | ||
|  |     } | ||
|  |     if (!options) { | ||
|  |       options = {} | ||
|  |     } | ||
|  | 
 | ||
|  |     // Overwrite and define settings with options if they exist.
 | ||
|  |     for (var key in settings) { | ||
|  |       if (typeof options[key] !== 'undefined') { | ||
|  |         this[key] = options[key] | ||
|  |       } else { | ||
|  |         this[key] = settings[key] | ||
|  |       } | ||
|  |     } | ||
|  | 
 | ||
|  |     // These should be treated as read-only properties
 | ||
|  | 
 | ||
|  |     /** The URL as resolved by the constructor. This is always an absolute URL. Read only. */ | ||
|  |     this.url = url | ||
|  | 
 | ||
|  |     /** The number of attempted reconnects since starting, or the last successful connection. Read only. */ | ||
|  |     this.reconnectAttempts = 0 | ||
|  | 
 | ||
|  |     /** | ||
|  |      * The current state of the connection. | ||
|  |      * Can be one of: WebSocket.CONNECTING, WebSocket.OPEN, WebSocket.CLOSING, WebSocket.CLOSED | ||
|  |      * Read only. | ||
|  |      */ | ||
|  |     this.readyState = WebSocket.CONNECTING | ||
|  | 
 | ||
|  |     /** | ||
|  |      * A string indicating the name of the sub-protocol the server selected; this will be one of | ||
|  |      * the strings specified in the protocols parameter when creating the WebSocket object. | ||
|  |      * Read only. | ||
|  |      */ | ||
|  |     this.protocol = null | ||
|  | 
 | ||
|  |     // Private state variables
 | ||
|  | 
 | ||
|  |     var self = this | ||
|  |     var ws | ||
|  |     var forcedClose = false | ||
|  |     var timedOut = false | ||
|  |     var eventTarget = document.createElement('div') | ||
|  | 
 | ||
|  |     // Wire up "on*" properties as event handlers
 | ||
|  | 
 | ||
|  |     eventTarget.addEventListener('open', function(event) { | ||
|  |       self.onopen(event) | ||
|  |     }) | ||
|  |     eventTarget.addEventListener('close', function(event) { | ||
|  |       self.onclose(event) | ||
|  |     }) | ||
|  |     eventTarget.addEventListener('connecting', function(event) { | ||
|  |       self.onconnecting(event) | ||
|  |     }) | ||
|  |     eventTarget.addEventListener('message', function(event) { | ||
|  |       self.onmessage(event) | ||
|  |     }) | ||
|  |     eventTarget.addEventListener('error', function(event) { | ||
|  |       self.onerror(event) | ||
|  |     }) | ||
|  | 
 | ||
|  |     // Expose the API required by EventTarget
 | ||
|  | 
 | ||
|  |     this.addEventListener = eventTarget.addEventListener.bind(eventTarget) | ||
|  |     this.removeEventListener = eventTarget.removeEventListener.bind(eventTarget) | ||
|  |     this.dispatchEvent = eventTarget.dispatchEvent.bind(eventTarget) | ||
|  | 
 | ||
|  |     /** | ||
|  |      * This function generates an event that is compatible with standard | ||
|  |      * compliant browsers and IE9 - IE11 | ||
|  |      * | ||
|  |      * This will prevent the error: | ||
|  |      * Object doesn't support this action | ||
|  |      * | ||
|  |      * http://stackoverflow.com/questions/19345392/why-arent-my-parameters-getting-passed-through-to-a-dispatched-event/19345563#19345563
 | ||
|  |      * @param s String The name that the event should use | ||
|  |      * @param args Object an optional object that the event will use | ||
|  |      */ | ||
|  |     function generateEvent(s, args) { | ||
|  |       var evt = document.createEvent('CustomEvent') | ||
|  |       evt.initCustomEvent(s, false, false, args) | ||
|  |       return evt | ||
|  |     } | ||
|  | 
 | ||
|  |     this.open = function(reconnectAttempt) { | ||
|  |       ws = new WebSocket(self.url, protocols || []) | ||
|  |       ws.binaryType = this.binaryType | ||
|  | 
 | ||
|  |       if (reconnectAttempt) { | ||
|  |         if (this.maxReconnectAttempts && this.reconnectAttempts > this.maxReconnectAttempts) { | ||
|  |           return | ||
|  |         } | ||
|  |       } else { | ||
|  |         eventTarget.dispatchEvent(generateEvent('connecting')) | ||
|  |         this.reconnectAttempts = 0 | ||
|  |       } | ||
|  | 
 | ||
|  |       if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |         console.debug('ReconnectingWebSocket', 'attempt-connect', self.url) | ||
|  |       } | ||
|  | 
 | ||
|  |       var localWs = ws | ||
|  |       var timeout = setTimeout(function() { | ||
|  |         if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |           console.debug('ReconnectingWebSocket', 'connection-timeout', self.url) | ||
|  |         } | ||
|  |         timedOut = true | ||
|  |         localWs.close() | ||
|  |         timedOut = false | ||
|  |       }, self.timeoutInterval) | ||
|  | 
 | ||
|  |       ws.onopen = function(event) { | ||
|  |         clearTimeout(timeout) | ||
|  |         if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |           console.debug('ReconnectingWebSocket', 'onopen', self.url) | ||
|  |         } | ||
|  |         self.protocol = ws.protocol | ||
|  |         self.readyState = WebSocket.OPEN | ||
|  |         self.reconnectAttempts = 0 | ||
|  |         var e = generateEvent('open') | ||
|  |         e.isReconnect = reconnectAttempt | ||
|  |         reconnectAttempt = false | ||
|  |         eventTarget.dispatchEvent(e) | ||
|  |       } | ||
|  | 
 | ||
|  |       ws.onclose = function(event) { | ||
|  |         clearTimeout(timeout) | ||
|  |         ws = null | ||
|  |         if (forcedClose) { | ||
|  |           self.readyState = WebSocket.CLOSED | ||
|  |           eventTarget.dispatchEvent(generateEvent('close')) | ||
|  |         } else { | ||
|  |           self.readyState = WebSocket.CONNECTING | ||
|  |           var e = generateEvent('connecting') | ||
|  |           e.code = event.code | ||
|  |           e.reason = event.reason | ||
|  |           e.wasClean = event.wasClean | ||
|  |           eventTarget.dispatchEvent(e) | ||
|  |           if (!reconnectAttempt && !timedOut) { | ||
|  |             if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |               console.debug('ReconnectingWebSocket', 'onclose', self.url) | ||
|  |             } | ||
|  |             eventTarget.dispatchEvent(generateEvent('close')) | ||
|  |           } | ||
|  | 
 | ||
|  |           var timeout = self.reconnectInterval * Math.pow(self.reconnectDecay, self.reconnectAttempts) | ||
|  |           setTimeout(function() { | ||
|  |             self.reconnectAttempts++ | ||
|  |             self.open(true) | ||
|  |           }, timeout > self.maxReconnectInterval ? self.maxReconnectInterval : timeout) | ||
|  |         } | ||
|  |       } | ||
|  |       ws.onmessage = function(event) { | ||
|  |         if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |           console.debug('ReconnectingWebSocket', 'onmessage', self.url, event.data) | ||
|  |         } | ||
|  |         var e = generateEvent('message') | ||
|  |         e.data = event.data | ||
|  |         eventTarget.dispatchEvent(e) | ||
|  |       } | ||
|  |       ws.onerror = function(event) { | ||
|  |         if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |           console.debug('ReconnectingWebSocket', 'onerror', self.url, event) | ||
|  |         } | ||
|  |         eventTarget.dispatchEvent(generateEvent('error')) | ||
|  |       } | ||
|  |     } | ||
|  | 
 | ||
|  |     // Whether or not to create a websocket upon instantiation
 | ||
|  |     if (this.automaticOpen == true) { | ||
|  |       this.open(false) | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Transmits data to the server over the WebSocket connection. | ||
|  |      * | ||
|  |      * @param data a text string, ArrayBuffer or Blob to send to the server. | ||
|  |      */ | ||
|  |     this.send = function(data) { | ||
|  |       if (ws) { | ||
|  |         if (self.debug || ReconnectingWebSocket.debugAll) { | ||
|  |           console.debug('ReconnectingWebSocket', 'send', self.url, data) | ||
|  |         } | ||
|  |         return ws.send(data) | ||
|  |       } else { | ||
|  |         throw 'INVALID_STATE_ERR : Pausing to reconnect websocket' | ||
|  |       } | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Closes the WebSocket connection or connection attempt, if any. | ||
|  |      * If the connection is already CLOSED, this method does nothing. | ||
|  |      */ | ||
|  |     this.close = function(code, reason) { | ||
|  |       // Default CLOSE_NORMAL code
 | ||
|  |       if (typeof code == 'undefined') { | ||
|  |         code = 1000 | ||
|  |       } | ||
|  |       forcedClose = true | ||
|  |       if (ws) { | ||
|  |         ws.close(code, reason) | ||
|  |       } | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Additional public API method to refresh the connection if still open (close, re-open). | ||
|  |      * For example, if the app suspects bad data / missed heart beats, it can try to refresh. | ||
|  |      */ | ||
|  |     this.refresh = function() { | ||
|  |       if (ws) { | ||
|  |         ws.close() | ||
|  |       } | ||
|  |     } | ||
|  |   } | ||
|  | 
 | ||
|  |   /** | ||
|  |    * An event listener to be called when the WebSocket connection's readyState changes to OPEN; | ||
|  |    * this indicates that the connection is ready to send and receive data. | ||
|  |    */ | ||
|  |   ReconnectingWebSocket.prototype.onopen = function(event) { | ||
|  |   } | ||
|  |   /** An event listener to be called when the WebSocket connection's readyState changes to CLOSED. */ | ||
|  |   ReconnectingWebSocket.prototype.onclose = function(event) { | ||
|  |   } | ||
|  |   /** An event listener to be called when a connection begins being attempted. */ | ||
|  |   ReconnectingWebSocket.prototype.onconnecting = function(event) { | ||
|  |   } | ||
|  |   /** An event listener to be called when a message is received from the server. */ | ||
|  |   ReconnectingWebSocket.prototype.onmessage = function(event) { | ||
|  |   } | ||
|  |   /** An event listener to be called when an error occurs. */ | ||
|  |   ReconnectingWebSocket.prototype.onerror = function(event) { | ||
|  |   } | ||
|  | 
 | ||
|  |   /** | ||
|  |    * Whether all instances of ReconnectingWebSocket should log debug messages. | ||
|  |    * Setting this to true is the equivalent of setting all instances of ReconnectingWebSocket.debug to true. | ||
|  |    */ | ||
|  |   ReconnectingWebSocket.debugAll = false | ||
|  | 
 | ||
|  |   ReconnectingWebSocket.CONNECTING = WebSocket.CONNECTING | ||
|  |   ReconnectingWebSocket.OPEN = WebSocket.OPEN | ||
|  |   ReconnectingWebSocket.CLOSING = WebSocket.CLOSING | ||
|  |   ReconnectingWebSocket.CLOSED = WebSocket.CLOSED | ||
|  | 
 | ||
|  |   return ReconnectingWebSocket | ||
|  | }) |