Implemented cancel connect.

remoting/webapp/me2mom/remoting.js

Index: remoting/webapp/me2mom/remoting.js
diff --git a/remoting/webapp/me2mom/remoting.js b/remoting/webapp/me2mom/remoting.js
index d88ad50b026fda136d248cd39501ee60f78e5dc9..d7586e380695785db9b663b8449eb859ff0d0f4f 100644
--- a/remoting/webapp/me2mom/remoting.js
+++ b/remoting/webapp/me2mom/remoting.js
@@ -157,6 +157,7 @@ remoting.init = function() {
   remoting.oauth2 = new remoting.OAuth2();
   remoting.debug =
       new remoting.DebugLog(document.getElementById('debug-messages'));
+  remoting.sessionId = 1;
 
   refreshEmail_();
   var email = getEmail();
@@ -378,20 +379,20 @@ function onStateChanged_() {
 }
 
 /**
-* This is the callback that the host plugin invokes to indicate that there
-* is additional debug log info to display.
-* @param {string} msg The message (which will not be localized) to be logged.
-*/
+ * This is the callback that the host plugin invokes to indicate that there
+ * is additional debug log info to display.
+ * @param {string} msg The message (which will not be localized) to be logged.
+ */
 function debugInfoCallback_(msg) {
   remoting.debug.log('plugin: ' + msg);
 }
 
 /**
-* Show a host-side error message.
-*
-* @param {string} errorTag The error message to be localized and displayed.
-* @return {void} Nothing.
-*/
+ * Show a host-side error message.
+ *
+ * @param {string} errorTag The error message to be localized and displayed.
+ * @return {void} Nothing.
+ */
 function showShareError_(errorTag) {
   var errorDiv = document.getElementById('host-plugin-error');
   l10n.localizeElementFromTag(errorDiv, errorTag);
@@ -399,6 +400,11 @@ function showShareError_(errorTag) {
   remoting.setMode(remoting.AppMode.HOST_SHARE_FAILED);
 }
 
+/**
+ * Cancel an active or pending share operation.
+ *
+ * @return {void} Nothing.
+ */
 remoting.cancelShare = function() {
   remoting.debug.log('Canceling share...');
   remoting.lastShareWasCancelled = true;
@@ -418,6 +424,20 @@ remoting.cancelShare = function() {
   disableTimeoutCountdown_();
 }
 
+/**
+ * Cancel an incomplete connect operation.
+ *
+ * @return {void} Nothing.
+ */
+remoting.cancelConnect = function() {
+  ++remoting.sessionId;
+  if (remoting.session) {
+    remoting.session.removePlugin();
+    remoting.session = null;
+  }
+  remoting.setMode(remoting.AppMode.HOME);
+}
+
 function updateStatistics() {
   if (!remoting.session)
     return;
@@ -460,6 +480,11 @@ function showToolbarPreview_() {
 }
 
 function onClientStateChange_(oldState) {
+  if (!remoting.session) {
+    // If the connection has been cancelled, then we no longer have a reference
+    // to the session object and should ignore any state changes.
+    return;
+  }
   var state = remoting.session.state;
   if (state == remoting.ClientSession.State.CREATED) {
     remoting.debug.log('Created plugin');
@@ -470,12 +495,12 @@ function onClientStateChange_(oldState) {
   } else if (state == remoting.ClientSession.State.INITIALIZING) {
     remoting.debug.log('Initializing connection');
   } else if (state == remoting.ClientSession.State.CONNECTED) {
-    remoting.setMode(remoting.AppMode.IN_SESSION);
-    recenterToolbar_();
-    showToolbarPreview_();
-    updateStatistics();
-    var accessCode = document.getElementById('access-code-entry');
-    accessCode.value = '';
+    if (remoting.session) {
+      remoting.setMode(remoting.AppMode.IN_SESSION);
+      recenterToolbar_();
+      showToolbarPreview_();
+      updateStatistics();
+    }
   } else if (state == remoting.ClientSession.State.CLOSED) {
     if (oldState == remoting.ClientSession.State.CONNECTED) {
       remoting.session.removePlugin();
@@ -515,6 +540,8 @@ function onClientStateChange_(oldState) {
 
 function startSession_() {
   remoting.debug.log('Starting session...');
+  var accessCode = document.getElementById('access-code-entry');
+  accessCode.value = '';  // The code has been validated and won't work again.
   remoting.username =
       /** @type {string} email must be non-NULL to get here */ getEmail();
   remoting.session =
@@ -547,7 +574,12 @@ function showConnectError_(errorTag) {
   remoting.setMode(remoting.AppMode.CLIENT_CONNECT_FAILED);
 }
 
-function parseServerResponse_(xhr) {
+function parseServerResponse_(xhr, sessionId) {
+  if (sessionId != remoting.sessionId) {
+    remoting.debug.log('ignoring request id ' + sessionId);
+    return;
+  }
+  ++remoting.sessionId;

[Wez, 2011/10/14 01:21:26]

Consider tweaking the xhr.get() call to return the XMLHttpRequest, and storing
that so that it can be abort()'d, to avoid the need for the sessionId logic.

[Jamie, 2011/10/14 18:17:07]

Done.

   remoting.debug.log('parseServerResponse: status = ' + xhr.status);
   if (xhr.status == 200) {
     var host = JSON.parse(xhr.responseText);
@@ -582,15 +614,17 @@ function resolveSupportId(supportId) {
     'Authorization': 'OAuth ' + remoting.oauth2.getAccessToken()
   };
 
+  var sessionId = remoting.sessionId;
   remoting.xhr.get(
       'https://www.googleapis.com/chromoting/v1/support-hosts/' +
           encodeURIComponent(supportId),
-      parseServerResponse_,
+      function(xhr) { parseServerResponse_(xhr, sessionId); },
       '',
       headers);
 }
 
 remoting.tryConnect = function() {
+  document.getElementById('cancel-button').disabled = false;
   if (remoting.oauth2.needsNewAccessToken()) {
     remoting.oauth2.refreshAccessToken(function(xhr) {
       if (remoting.oauth2.needsNewAccessToken()) {
@@ -634,9 +668,14 @@ remoting.tryConnectWithWcs = function() {
 }
 
 remoting.cancelPendingOperation = function() {
-  document.getElementById('cancel-button').disabled = true;
-  if (remoting.getMajorMode() == remoting.AppMode.HOST) {
+   document.getElementById('cancel-button').disabled = true;

[Wez, 2011/10/14 01:21:26]

nit: Indentation.

[Jamie, 2011/10/14 18:17:07]

Done.

+  switch (remoting.getMajorMode()) {
+   case remoting.AppMode.HOST:

[Wez, 2011/10/14 01:21:26]

nit: Is this the right indentation for case?

[Jamie, 2011/10/14 18:17:07]

Apparently not. Fixed.

     remoting.cancelShare();
+    break;
+   case remoting.AppMode.CLIENT:
+    remoting.cancelConnect();
+    break;
   }
 }