1 // ========================================================================== 2 // Project: SC.WebSocket 3 // Copyright: ©2013 Nicolas BADIA and contributors 4 // License: Licensed under MIT license (see license.js) 5 // ========================================================================== 6 7 sc_require('mixins/websocket_delegate'); 8 9 /** 10 @class 11 12 Implements SproutCore run loop aware event handling for WebSocket. Using SC.WebSocket ensures 13 that the run loop runs on each WebSocket event and provides a useful skeleton for handling 14 WebSocket events. 15 16 Example Usage: 17 18 // Create a WebSocket connection. 19 var ws = SC.WebSocket.create({ 20 server: 'ws://server', 21 }); 22 23 // Assign target and methods for events. 24 ws.notify('onopen', this, 'wsOpened'); 25 ws.notify('onmessage', this, 'wsReceivedMessage'); 26 ws.notify('onclose', this, 'wsClosed'); 27 ws.connect(); 28 29 // Send a message through the WebSocket. 30 ws.send('hello server'); 31 32 @since SproutCore 1.11 33 @extends SC.Object 34 @extends SC.DelegateSupport 35 @author Nicolas BADIA 36 */ 37 SC.WebSocket = SC.Object.extend(SC.DelegateSupport, SC.WebSocketDelegate, 38 /** @scope SC.WebSocket.prototype */ { 39 40 /** 41 The URL of the WebSocket server. 42 43 @type String 44 @default null 45 */ 46 server: null, 47 48 /** 49 Whether the connection is open or not. 50 51 @type Boolean 52 @readOnly 53 */ 54 isConnected: false, 55 56 /** 57 In order to handle authentification, set `isAuth` to `false` in the 58 `webSocketDidOpen` delegate method just after sending a request to 59 authenticate the connection. This way, any futher messages will be put in the 60 queue until the server tells you that the connection is authenticated. Once it 61 is, you should set `isAuth` to `true` to resume the queue. 62 63 If you don't need authentication, leave `isAuth` as `null`. 64 65 @type Boolean 66 @default null 67 */ 68 isAuth: null, 69 70 /** 71 Processes the messages as JSON if possible. 72 73 @type Boolean 74 @default true 75 */ 76 isJSON: true, 77 78 /** 79 A WebSocket delegate. 80 81 @see SC.WebSocketDelegate 82 @type SC.WebSocketDelegate 83 @default null 84 */ 85 delegate: null, 86 87 /** 88 Whether to attempt to reconnect automatically if the connection is closed or not. 89 90 @type SC.WebSocketDelegate 91 @default true 92 */ 93 autoReconnect: true, 94 95 /** 96 The interval in milliseconds to wait before trying to reconnect. 97 98 @type SC.WebSocketDelegate 99 @default null 100 */ 101 reconnectInterval: 10000, // 10 seconds 102 103 // .......................................................... 104 // PUBLIC METHODS 105 // 106 107 /** 108 Open the WebSocket connection. 109 110 @returns {SC.WebSocket} The SC.WebSocket object. 111 */ 112 connect: function() { 113 // If not supported or already connected, return. 114 if (!SC.platform.supportsWebSocket || this.socket) return this; 115 116 // Connect. 117 try { 118 var socket = this.socket = new WebSocket(this.get('server')); 119 120 socket.onopen = function() { 121 SC.run(function () { 122 this.onOpen.apply(this, arguments); 123 }, this); 124 }; 125 126 socket.onmessage = function() { 127 SC.run(function () { 128 this.onMessage.apply(this, arguments); 129 }, this); 130 }; 131 132 socket.onclose = function() { 133 SC.run(function () { 134 this.onClose.apply(this, arguments); 135 }, this); 136 }; 137 138 socket.onerror = function() { 139 SC.run(function () { 140 this.onError.apply(this, arguments); 141 }, this); 142 }; 143 } catch (e) { 144 SC.error('An error has occurred while connnecting to the websocket server: ' + e); 145 } 146 147 return this; 148 }, 149 150 /** 151 Close the connection. 152 153 @param {Number} code A numeric value indicating the status code explaining why the connection is being closed. If this parameter is not specified, a default value of 1000 (indicating a normal "transaction complete" closure) is assumed. 154 @param {String} reason A human-readable string explaining why the connection is closing. This string must be no longer than 123 bytes of UTF-8 text (not characters). 155 @returns {SC.WebSocket} The SC.WebSocket object. 156 */ 157 close: function(code, reason) { 158 var socket = this.socket; 159 160 if (socket && socket.readyState === SC.WebSocket.OPEN) { 161 this.socket.close(code, reason); 162 } 163 164 return this; 165 }, 166 167 /** 168 Configures a callback to execute when an event happens. You must pass at least a target and 169 method to this and optionally an event name. 170 171 You may also pass additional arguments which will then be passed along to your callback. 172 173 Example: 174 175 var websocket = SC.WebSocket.create({ server: 'ws://server' }).connect(); 176 177 webSocket.notify('onopen', this, 'wsWasOpened'); 178 webSocket.notify('onmessage', this, 'wsReceivedMessage'); 179 webSocket.notify('onclose', this, 'wsWasClose'); 180 webSocket.notify('onerror', this, 'wsDidError'); 181 182 ## Callback Format 183 184 Your notification callback should expect to receive the WebSocket object as 185 the first parameter and the event or message; plus any additional parameters that you pass. If your callback handles the notification and to prevent further handling, it 186 should return YES. 187 188 @param {String} target String Event name. 189 @param {Object} target The target object for the callback action. 190 @param {String|Function} action The method name or function to call on the target. 191 @returns {SC.WebSocket} The SC.WebSocket object. 192 */ 193 notify: function(event, target, action) { 194 var args, 195 i, len; 196 197 if (SC.typeOf(event) !== SC.T_STRING) { 198 // Fast arguments access. 199 // Accessing `arguments.length` is just a Number and doesn't materialize the `arguments` object, which is costly. 200 args = new Array(arguments.length - 2); // SC.A(arguments).slice(2) 201 for (i = 0, len = args.length; i < len; i++) { args[i] = arguments[i + 2]; } 202 203 // Shift the arguments 204 action = target; 205 target = event; 206 event = 'onmessage'; 207 } else { 208 if (arguments.length > 3) { 209 // Fast arguments access. 210 // Accessing `arguments.length` is just a Number and doesn't materialize the `arguments` object, which is costly. 211 args = new Array(arguments.length - 3); // SC.A(arguments).slice(3) 212 for (i = 0, len = args.length; i < len; i++) { args[i] = arguments[i + 3]; } 213 } else { 214 args = []; 215 } 216 } 217 218 var listeners = this.get('listeners'); 219 if (!listeners) { this.set('listeners', listeners = {}); } 220 if(!listeners[event]) { listeners[event] = []; } 221 222 //@if(debug) 223 for (i = listeners[event].length - 1; i >= 0; i--) { 224 var listener = listeners[event][i]; 225 if (listener.event === event && listener.target === target && listener.action === action) { 226 SC.warn("Developer Warning: This listener is already defined."); 227 } 228 } 229 //@endif 230 231 // Add another listener for the given event name. 232 listeners[event].push({target: target, action: action, args: args}); 233 234 return this; 235 }, 236 237 /** 238 Send the message on the WebSocket. If the connection is not yet open or authenticated (as 239 necessary), the message will be put in the queue. 240 241 If `isJSON` is true (the default for SC.WebSocket), the message will be stringified JSON. 242 243 @param {String|Object} message The message to send. 244 @returns {SC.WebSocket} 245 */ 246 send: function(message) { 247 if (this.isConnected === true && this.isAuth !== false) { 248 if (this.isJSON) { 249 message = JSON.stringify(message); 250 } 251 252 this.socket.send(message); 253 } else { 254 this.addToQueue(message); 255 } 256 return this; 257 }, 258 259 // .......................................................... 260 // PRIVATE METHODS 261 // 262 263 /** 264 @private 265 */ 266 onOpen: function(event) { 267 var del = this.get('objectDelegate'); 268 269 this.set('isConnected', true); 270 271 var ret = del.webSocketDidOpen(this, event); 272 if (ret !== true) this._notifyListeners('onopen', event); 273 274 this.fireQueue(); 275 }, 276 277 /** 278 @private 279 */ 280 onMessage: function(messageEvent) { 281 if (messageEvent) { 282 var del = this.get('objectDelegate'), 283 message, 284 data, 285 ret; 286 287 message = data = messageEvent.data; 288 ret = del.webSocketDidReceiveMessage(this, data); 289 290 if (ret !== true) { 291 if (this.isJSON) { 292 message = JSON.parse(data); 293 } 294 this._notifyListeners('onmessage', message); 295 } 296 } 297 298 // If there is message in the queue, we fire them 299 this.fireQueue(); 300 }, 301 302 /** 303 @private 304 */ 305 onClose: function(closeEvent) { 306 var del = this.get('objectDelegate'); 307 308 this.set('isConnected', false); 309 this.set('isAuth', null); 310 this.socket = null; 311 312 var ret = del.webSocketDidClose(this, closeEvent); 313 314 if (ret !== true) { 315 this._notifyListeners('onclose', closeEvent); 316 this.tryReconnect(); 317 } 318 }, 319 320 /** 321 @private 322 */ 323 onError: function(event) { 324 var del = this.get('objectDelegate'), 325 ret = del.webSocketDidError(this, event); 326 327 if (ret !== true) this._notifyListeners('onerror', event); 328 }, 329 330 /** 331 @private 332 333 Add the message to the queue 334 */ 335 addToQueue: function(message) { 336 var queue = this.queue; 337 if (!queue) { this.queue = queue = []; } 338 339 queue.push(message); 340 }, 341 342 /** 343 @private 344 345 Send the messages from the queue. 346 */ 347 fireQueue: function() { 348 var queue = this.queue; 349 if (!queue || queue.length === 0) return; 350 351 queue = SC.A(queue); 352 this.queue = null; 353 354 for (var i = 0, len = queue.length; i < len; i++) { 355 var message = queue[i]; 356 this.send(message); 357 } 358 }, 359 360 /** 361 @private 362 */ 363 tryReconnect: function() { 364 if (!this.get('autoReconnect')) return; 365 366 var that = this; 367 setTimeout(function() { that.connect(); }, this.get('reconnectInterval')); 368 }, 369 370 /** 371 @private 372 373 Will notify each listener. Returns true if any of the listeners handle. 374 */ 375 _notifyListeners: function(event, message) { 376 var listeners = (this.listeners || {})[event], notifier, target, action, args; 377 if (!listeners) { return NO; } 378 379 var handled = NO, 380 len = listeners.length; 381 382 for (var i = 0; i < len; i++) { 383 notifier = listeners[i]; 384 args = (notifier.args || []).copy(); 385 args.unshift(message); 386 args.unshift(this); 387 388 target = notifier.target; 389 action = notifier.action; 390 if (SC.typeOf(action) === SC.T_STRING) { action = target[action]; } 391 392 handled = action.apply(target, args); 393 if (handled === true) return handled; 394 } 395 396 return handled; 397 }, 398 399 /** 400 @private 401 */ 402 objectDelegate: function () { 403 var del = this.get('delegate'); 404 return this.delegateFor('isWebSocketDelegate', del, this); 405 }.property('delegate').cacheable(), 406 407 // .......................................................... 408 // PRIVATE PROPERTIES 409 // 410 411 /** 412 @private 413 414 @type WebSocket 415 @default null 416 */ 417 socket: null, 418 419 /** 420 @private 421 422 @type Object 423 @default null 424 */ 425 listeners: null, 426 427 /** 428 @private 429 430 Messages that needs to be send once the connection is open. 431 432 @type Array 433 @default null 434 */ 435 queue: null, 436 437 }); 438 439 // Class Methods 440 SC.WebSocket.mixin( /** @scope SC.WebSocket */ { 441 442 // .......................................................... 443 // CONSTANTS 444 // 445 446 /** 447 The connection is not yet open. 448 449 @static 450 @constant 451 @type Number 452 @default 0 453 */ 454 CONNECTING: 0, 455 456 /** 457 The connection is open and ready to communicate. 458 459 @static 460 @constant 461 @type Number 462 @default 1 463 */ 464 OPEN: 1, 465 466 /** 467 The connection is in the process of closing. 468 469 @static 470 @constant 471 @type Number 472 @default 2 473 */ 474 CLOSING: 2, 475 476 /** 477 The connection is closed or couldn't be opened. 478 479 @static 480 @constant 481 @type Number 482 @default 3 483 */ 484 CLOSED: 3, 485 486 }); 487