1// Copyright 2014 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5/** 6 * @fileoverview 7 * 8 * It2MeHelperChannel relays messages between Hangouts and Chrome Remote Desktop 9 * (webapp) for the helper (the Hangouts participant who is giving remote 10 * assistance). 11 * 12 * It runs in the background page and contains two chrome.runtime.Port objects, 13 * representing connections to the webapp and hangout, respectively. 14 * 15 * Connection is always initiated from Hangouts by calling 16 * var port = chrome.runtime.connect({name:'it2me.helper.hangout'}, extId). 17 * port.postMessage('hello') 18 * If the webapp is not installed, |port.onDisconnect| will fire. 19 * If the webapp is installed, Hangouts will receive a hello response with the 20 * list of supported features. 21 * 22 * Hangout It2MeHelperChannel Chrome Remote Desktop 23 * |-----runtime.connect() ------>| | 24 * |--------hello message-------->| | 25 * | |<-----helloResponse message-----| 26 * |-------connect message------->| | 27 * | |-------appLauncher.launch()---->| 28 * | |<------runtime.connect()------- | 29 * | |<-----sessionStateChanged------ | 30 * |<----sessionStateChanged------| | 31 * 32 * Disconnection can be initiated from either side: 33 * 1. In the normal flow initiated from hangout 34 * Hangout It2MeHelperChannel Chrome Remote Desktop 35 * |-----disconnect message------>| | 36 * |<-sessionStateChanged(CLOSED)-| | 37 * | |-----appLauncher.close()------>| 38 * 39 * 2. In the normal flow initiated from webapp 40 * Hangout It2MeHelperChannel Chrome Remote Desktop 41 * | |<-sessionStateChanged(CLOSED)--| 42 * | |<--------port.disconnect()-----| 43 * |<--------port.disconnect()----| | 44 * 45 * 2. If hangout crashes 46 * Hangout It2MeHelperChannel Chrome Remote Desktop 47 * |---------port.disconnect()--->| | 48 * | |--------port.disconnect()----->| 49 * | |------appLauncher.close()----->| 50 * 51 * 3. If webapp crashes 52 * Hangout It2MeHelperChannel Chrome Remote Desktop 53 * | |<-------port.disconnect()------| 54 * |<-sessionStateChanged(FAILED)-| | 55 * |<--------port.disconnect()----| | 56 */ 57 58'use strict'; 59 60/** @suppress {duplicate} */ 61var remoting = remoting || {}; 62 63/** 64 * @param {remoting.AppLauncher} appLauncher 65 * @param {chrome.runtime.Port} hangoutPort Represents an active connection to 66 * Hangouts. 67 * @param {function(remoting.It2MeHelperChannel)} onDisconnectCallback Callback 68 * to notify when the connection is torn down. IT2MeService uses this 69 * callback to dispose of the channel object. 70 * @constructor 71 */ 72remoting.It2MeHelperChannel = 73 function(appLauncher, hangoutPort, onDisconnectCallback) { 74 75 /** 76 * @type {remoting.AppLauncher} 77 * @private 78 */ 79 this.appLauncher_ = appLauncher; 80 81 /** 82 * @type {chrome.runtime.Port} 83 * @private 84 */ 85 this.hangoutPort_ = hangoutPort; 86 87 /** 88 * @type {chrome.runtime.Port} 89 * @private 90 */ 91 this.webappPort_ = null; 92 93 /** 94 * @type {string} 95 * @private 96 */ 97 this.instanceId_ = ''; 98 99 /** 100 * @type {remoting.ClientSession.State} 101 * @private 102 */ 103 this.sessionState_ = remoting.ClientSession.State.CONNECTING; 104 105 /** 106 * @type {?function(remoting.It2MeHelperChannel)} 107 * @private 108 */ 109 this.onDisconnectCallback_ = onDisconnectCallback; 110 111 this.onWebappMessageRef_ = this.onWebappMessage_.bind(this); 112 this.onWebappDisconnectRef_ = this.onWebappDisconnect_.bind(this); 113 this.onHangoutMessageRef_ = this.onHangoutMessage_.bind(this); 114 this.onHangoutDisconnectRef_ = this.onHangoutDisconnect_.bind(this); 115}; 116 117/** @enum {string} */ 118remoting.It2MeHelperChannel.HangoutMessageTypes = { 119 HELLO: 'hello', 120 HELLO_RESPONSE: 'helloResponse', 121 CONNECT: 'connect', 122 DISCONNECT: 'disconnect', 123 ERROR: 'error' 124}; 125 126/** @enum {string} */ 127remoting.It2MeHelperChannel.Features = { 128 REMOTE_ASSISTANCE: 'remoteAssistance' 129}; 130 131/** @enum {string} */ 132remoting.It2MeHelperChannel.WebappMessageTypes = { 133 SESSION_STATE_CHANGED: 'sessionStateChanged' 134}; 135 136remoting.It2MeHelperChannel.prototype.init = function() { 137 this.hangoutPort_.onMessage.addListener(this.onHangoutMessageRef_); 138 this.hangoutPort_.onDisconnect.addListener(this.onHangoutDisconnectRef_); 139}; 140 141/** @return {string} */ 142remoting.It2MeHelperChannel.prototype.instanceId = function() { 143 return this.instanceId_; 144}; 145 146/** 147 * @param {{method:string, data:Object.<string,*>}} message 148 * @return {boolean} whether the message is handled or not. 149 * @private 150 */ 151remoting.It2MeHelperChannel.prototype.onHangoutMessage_ = function(message) { 152 try { 153 var MessageTypes = remoting.It2MeHelperChannel.HangoutMessageTypes; 154 switch (message.method) { 155 case MessageTypes.CONNECT: 156 this.launchWebapp_(message); 157 return true; 158 case MessageTypes.DISCONNECT: 159 this.closeWebapp_(message); 160 return true; 161 case MessageTypes.HELLO: 162 this.hangoutPort_.postMessage({ 163 method: MessageTypes.HELLO_RESPONSE, 164 supportedFeatures: base.values(remoting.It2MeHelperChannel.Features) 165 }); 166 return true; 167 } 168 throw new Error('Unknown message method=' + message.method); 169 } catch(e) { 170 var error = /** @type {Error} */ e; 171 this.sendErrorResponse_(this.hangoutPort_, error, message); 172 } 173 return false; 174}; 175 176/** 177 * Disconnect the existing connection to the helpee. 178 * 179 * @param {{method:string, data:Object.<string,*>}} message 180 * @private 181 */ 182remoting.It2MeHelperChannel.prototype.closeWebapp_ = 183 function(message) { 184 // TODO(kelvinp): Closing the v2 app currently doesn't disconnect the IT2me 185 // session (crbug.com/402137), so send an explicit notification to Hangouts. 186 this.sessionState_ = remoting.ClientSession.State.CLOSED; 187 this.hangoutPort_.postMessage({ 188 method: 'sessionStateChanged', 189 state: this.sessionState_ 190 }); 191 this.appLauncher_.close(this.instanceId_); 192}; 193 194/** 195 * Launches the web app. 196 * 197 * @param {{method:string, data:Object.<string,*>}} message 198 * @private 199 */ 200remoting.It2MeHelperChannel.prototype.launchWebapp_ = 201 function(message) { 202 var accessCode = getStringAttr(message, 'accessCode'); 203 if (!accessCode) { 204 throw new Error('Access code is missing'); 205 } 206 207 // Launch the webapp. 208 this.appLauncher_.launch({ 209 mode: 'hangout', 210 accessCode: accessCode 211 }).then( 212 /** 213 * @this {remoting.It2MeHelperChannel} 214 * @param {string} instanceId 215 */ 216 function(instanceId){ 217 this.instanceId_ = instanceId; 218 }.bind(this)); 219}; 220 221/** 222 * @private 223 */ 224remoting.It2MeHelperChannel.prototype.onHangoutDisconnect_ = function() { 225 this.appLauncher_.close(this.instanceId_); 226 this.unhookPorts_(); 227}; 228 229/** 230 * @param {chrome.runtime.Port} port The port represents a connection to the 231 * webapp. 232 * @param {string} id The id of the tab or window that is hosting the webapp. 233 */ 234remoting.It2MeHelperChannel.prototype.onWebappConnect = function(port, id) { 235 base.debug.assert(id === this.instanceId_); 236 base.debug.assert(this.hangoutPort_ !== null); 237 238 // Hook listeners. 239 port.onMessage.addListener(this.onWebappMessageRef_); 240 port.onDisconnect.addListener(this.onWebappDisconnectRef_); 241 this.webappPort_ = port; 242}; 243 244/** @param {chrome.runtime.Port} port The webapp port. */ 245remoting.It2MeHelperChannel.prototype.onWebappDisconnect_ = function(port) { 246 // If the webapp port got disconnected while the session is still connected, 247 // treat it as an error. 248 var States = remoting.ClientSession.State; 249 if (this.sessionState_ === States.CONNECTING || 250 this.sessionState_ === States.CONNECTED) { 251 this.sessionState_ = States.FAILED; 252 this.hangoutPort_.postMessage({ 253 method: 'sessionStateChanged', 254 state: this.sessionState_ 255 }); 256 } 257 this.unhookPorts_(); 258}; 259 260/** 261 * @param {{method:string, data:Object.<string,*>}} message 262 * @private 263 */ 264remoting.It2MeHelperChannel.prototype.onWebappMessage_ = function(message) { 265 try { 266 console.log('It2MeHelperChannel id=' + this.instanceId_ + 267 ' incoming message method=' + message.method); 268 var MessageTypes = remoting.It2MeHelperChannel.WebappMessageTypes; 269 switch (message.method) { 270 case MessageTypes.SESSION_STATE_CHANGED: 271 var state = getNumberAttr(message, 'state'); 272 this.sessionState_ = 273 /** @type {remoting.ClientSession.State} */ state; 274 this.hangoutPort_.postMessage(message); 275 return true; 276 } 277 throw new Error('Unknown message method=' + message.method); 278 } catch(e) { 279 var error = /** @type {Error} */ e; 280 this.sendErrorResponse_(this.webappPort_, error, message); 281 } 282 return false; 283}; 284 285remoting.It2MeHelperChannel.prototype.unhookPorts_ = function() { 286 if (this.webappPort_) { 287 this.webappPort_.onMessage.removeListener(this.onWebappMessageRef_); 288 this.webappPort_.onDisconnect.removeListener(this.onWebappDisconnectRef_); 289 this.webappPort_.disconnect(); 290 this.webappPort_ = null; 291 } 292 293 if (this.hangoutPort_) { 294 this.hangoutPort_.onMessage.removeListener(this.onHangoutMessageRef_); 295 this.hangoutPort_.onDisconnect.removeListener(this.onHangoutDisconnectRef_); 296 this.hangoutPort_.disconnect(); 297 this.hangoutPort_ = null; 298 } 299 300 if (this.onDisconnectCallback_) { 301 this.onDisconnectCallback_(this); 302 this.onDisconnectCallback_ = null; 303 } 304}; 305 306/** 307 * @param {chrome.runtime.Port} port 308 * @param {string|Error} error 309 * @param {?{method:string, data:Object.<string,*>}=} opt_incomingMessage 310 * @private 311 */ 312remoting.It2MeHelperChannel.prototype.sendErrorResponse_ = 313 function(port, error, opt_incomingMessage) { 314 if (error instanceof Error) { 315 error = error.message; 316 } 317 318 console.error('Error responding to message method:' + 319 (opt_incomingMessage ? opt_incomingMessage.method : 'null') + 320 ' error:' + error); 321 port.postMessage({ 322 method: remoting.It2MeHelperChannel.HangoutMessageTypes.ERROR, 323 message: error, 324 request: opt_incomingMessage 325 }); 326}; 327