[Webapp Refactor] Cleans up the ClientSession.EventHandler interface.

remoting/webapp/crd/js/client_session.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview
  * Class handling creation and teardown of a remoting client session.
  *
  * The ClientSession class controls lifetime of the client plugin
  * object and provides the plugin with the functionality it needs to
@@ skipping 70 matching lines @@
   plugin.setConnectionEventHandler(this);
 
   /** @private  */
   this.connectedDisposables_ = new base.Disposables();
 
   this.defineEvents(Object.keys(remoting.ClientSession.Events));
 };
 
 /** @enum {string} */
 remoting.ClientSession.Events = {
-  stateChanged: 'stateChanged', // deprecated.
-  videoChannelStateChanged: 'videoChannelStateChanged',
+  videoChannelStateChanged: 'videoChannelStateChanged'
 };
 
 /**
  * @interface
  * [START]-------> [onConnected] ------> [onDisconnected]
- *    |                              |
- *    |-----> [OnConnectionFailed]   |----> [onError]
+ *    |
+ *    |-----> [OnConnectionFailed]
  *
- * TODO(kelvinp): Route session state changes through this interface.
  */
 remoting.ClientSession.EventHandler = function() {};
 
 /**
  * Called when the connection failed before it is connected.
  *
  * @param {!remoting.Error} error
  */
 remoting.ClientSession.EventHandler.prototype.onConnectionFailed =
     function(error) {};
 
 /**
  * Called when a new session has been connected.  The |connectionInfo| will be
- * valid until onDisconnected() or onError() is called.
+ * valid until onDisconnected() is called.
  *
  * @param {!remoting.ConnectionInfo} connectionInfo
  */
 remoting.ClientSession.EventHandler.prototype.onConnected =
     function(connectionInfo) {};
 
 /**
  * Called when the current session has been disconnected.
+ *
+ * @param {!remoting.Error} reason Reason that the session is disconnected.
+ *     Set to remoting.Error.none() if there is no error.
  */
-remoting.ClientSession.EventHandler.prototype.onDisconnected = function() {};
-
-/**
- * Called when an error needs to be displayed to the user.
- * @param {!remoting.Error} error
- */
-remoting.ClientSession.EventHandler.prototype.onError = function(error) {};
+remoting.ClientSession.EventHandler.prototype.onDisconnected =
+    function(reason) {};
 
 // Note that the positive values in both of these enums are copied directly
 // from connection_to_host.h and must be kept in sync. Code in
 // chromoting_instance.cc converts the C++ enums into strings that must match
 // the names given here.
 // The negative values represent state transitions that occur within the
 // web-app that have no corresponding plugin state transition.
 /** @enum {number} */
 remoting.ClientSession.State = {
   CONNECTION_CANCELED: -3,  // Connection closed (gracefully) before connecting.
@@ skipping 16 matching lines @@
  * @param {string} state The state name.
  * @return {remoting.ClientSession.State} The session state enum value.
  */
 remoting.ClientSession.State.fromString = function(state) {
   if (!remoting.ClientSession.State.hasOwnProperty(state)) {
     throw "Invalid ClientSession.State: " + state;
   }
   return remoting.ClientSession.State[state];
 };
 
-/**
-  @param {remoting.ClientSession.State} current
-  @param {remoting.ClientSession.State} previous
-  @constructor
-*/
-remoting.ClientSession.StateEvent = function(current, previous) {
-  /** @type {remoting.ClientSession.State} */
-  this.previous = previous
-
-  /** @type {remoting.ClientSession.State} */
-  this.current = current;
-};
-
 /** @enum {number} */
 remoting.ClientSession.ConnectionError = {
   UNKNOWN: -1,
   NONE: 0,
   HOST_IS_OFFLINE: 1,
   SESSION_REJECTED: 2,
   INCOMPATIBLE_PROTOCOL: 3,
   NETWORK_FAILURE: 4,
   HOST_OVERLOAD: 5
 };
@@ skipping 87 matching lines @@
 /**
  * Disconnect the current session with a particular |error|.  The session will
  * raise a |stateChanged| event in response to it.  The caller should then call
  * dispose() to remove and destroy the <embed> element.
  *
  * @param {!remoting.Error} error The reason for the disconnection.  Use
  *    remoting.Error.none() if there is no error.
  * @return {void} Nothing.
  */
 remoting.ClientSession.prototype.disconnect = function(error) {
+  if (this.isFinished()) {
+    return;

[Jamie, 2015/04/24 18:09:09]

This appears in both your CLs.

+  }
+
   this.sendIq_(
       '<cli:iq ' +
           'to="' + this.host_.jabberId + '" ' +
           'type="set" ' +
           'id="session-terminate" ' +
           'xmlns:cli="jabber:client">' +
         '<jingle ' +
             'xmlns="urn:xmpp:jingle:1" ' +
             'action="session-terminate" ' +
             'sid="' + this.sessionId_ + '">' +
@@ skipping 246 matching lines @@
     case remoting.ClientSession.State.AUTHENTICATED:
       console.log('Connection authenticated.');
       break;
 
     case remoting.ClientSession.State.INITIALIZING:
       console.log('Connection initializing .');
       break;
 
     case remoting.ClientSession.State.CLOSED:
       console.log('Connection closed.');
-      this.listener_.onDisconnected();
+      this.listener_.onDisconnected(remoting.Error.none());
       break;
 
     case remoting.ClientSession.State.CONNECTION_CANCELED:
     case remoting.ClientSession.State.FAILED:
       error = this.getError();
       if (!error.isNone()) {
         console.error('Connection failed: ' + error.toString());
       }
       this.listener_.onConnectionFailed(error);
       break;
 
     case remoting.ClientSession.State.CONNECTION_DROPPED:
       error = this.getError();
       console.error('Connection dropped: ' + error.toString());
-      this.listener_.onError(error);
+      this.listener_.onDisconnected(error);
       break;
 
     default:
       console.error('Unexpected client plugin state: ' + newState);
-      // This should only happen if the web-app and client plugin get out of
-      // sync, and even then the version check should ensure compatibility.
-      this.listener_.onError(
-          new remoting.Error(remoting.Error.Tag.MISSING_PLUGIN));
   }
-
-  this.raiseEvent(remoting.ClientSession.Events.stateChanged,
-    new remoting.ClientSession.StateEvent(newState, oldState)
-  );
 };
 
 /**
  * @param {remoting.ClientSession.State} previous
  * @param {remoting.ClientSession.State} current
  * @return {remoting.ClientSession.State}
  * @private
  */
 remoting.ClientSession.prototype.translateState_ = function(previous, current) {
   var State = remoting.ClientSession.State;
@@ skipping 24 matching lines @@
  * For example, if attempting a connection using a cached JID, host-offline
  * errors should not be logged because the JID will be refreshed and the
  * connection retried.
  *
  * @param {boolean} enable True to log host-offline errors; false to suppress.
  */
 remoting.ClientSession.prototype.logHostOfflineErrors = function(enable) {
   this.logHostOfflineErrors_ = enable;
 };