Handle authentication failures in the v2 app by restarting the app

remoting/webapp/crd/js/identity.js

Index: remoting/webapp/crd/js/identity.js
diff --git a/remoting/webapp/crd/js/identity.js b/remoting/webapp/crd/js/identity.js
index aef0f2c6f984444844d7002e1f4d827a90dfb09b..dbf476ca4b49d60e26911458072f8c7d06e57af4 100644
--- a/remoting/webapp/crd/js/identity.js
+++ b/remoting/webapp/crd/js/identity.js
@@ -35,6 +35,8 @@ remoting.Identity = function(consentCallback) {
   this.fullName_ = '';
   /** @type {Array.<remoting.Identity.Callbacks>} */
   this.pendingCallbacks_ = [];
+  /** @type {Promise} */
+  this.handleAuthFailurePromise_ = null;
 };
 
 /**
@@ -75,18 +77,59 @@ remoting.Identity.prototype.callWithNewToken = function(onOk, onError) {
     chrome.identity.removeCachedAuthToken(
         {'token': token },
         that.callWithToken.bind(that, onOk, onError));
-  };
+  }
 
   this.callWithToken(revokeToken, onError);
 };
 
 /**
+ * Removes the cached token and prompts the user to get a new one.
+ * @return {Promise}  A promise that resolves when a new token is fetched.
+ */
+remoting.Identity.prototype.handleAuthFailure = function() {
+  if (!this.handleAuthFailurePromise_) {
+    var that = this;
+
+    var revokeToken = base.Promise.as(this.removeCachedAuthToken_, []);

[Jamie, 2015/01/23 23:33:27]

Using Promise.as to Promisify an API we own is a little odd. We should instead
just make that API use promises natively. That's out of scope for this CL, but
it would be more consistent if you used callbacks for this new API. I think it
would be more readable too--I'm having trouble working out exactly what's going
on here.

[kelvinp, 2015/01/28 00:26:46]

Agreed. I have converted the private API (removeCachedToken_) to use promise as
well.  The promise here is nice because it guarantees that if a token revoke is
in progress, we won't try to invoke another revoke.  If I use callbacks, I would
need to create an array of token revoke callbacks and notify each one of them,
when they are done. I also add more comments to explain each step.  Let me know
if there are other ways that I can clarify it better.

+
+    this.handleAuthFailurePromise_= revokeToken.then(function() {
+      return base.Promise.as(that.consentCallback_, []);
+    }).then(function(){
+      return base.Promise.as(
+          chrome.identity.getAuthToken, [{ 'interactive': true }]);
+    }).then(
+      /** @param {string} token */
+      function(token) {
+        that.handleAuthFailurePromise_ = null;
+        if (token) {
+          return Promise.resolve(token);
+        }
+        return Promise.reject(remoting.Error.NOT_AUTHENTICATED);
+      }
+    );
+  }
+  return this.handleAuthFailurePromise_;
+};
+
+/**
+ * Removes the cached token, prompts the user to get a new one and
+ *   relaunches the current window.
+ * @return {void}  Nothing.
+ */
+remoting.Identity.prototype.handleAuthFailureAndRelaunch = function() {
+  this.handleAuthFailure().then(function() {
+    base.RemoteMethods.invoke(remoting.ActivationHandler.Request.RELAUNCH,
+                              [chrome.app.window.current().id]);
+  });
+};
+
+/**
  * Remove the cached auth token, if any.
  *
  * @param {function():void} onDone Completion callback.
  * @return {void} Nothing.
  */
-remoting.Identity.prototype.removeCachedAuthToken = function(onDone) {
+remoting.Identity.prototype.removeCachedAuthToken_ = function(onDone) {

[Jamie, 2015/01/23 23:33:27]

Underscore and @private should go hand-in-hand. Please either remove the
underscore or add @private.

[kelvinp, 2015/01/28 00:26:46]

Done.

   /** @param {string} token */
   var onToken = function(token) {
     if (token) {