[Webapp Refactor] Remove It2Me connection code from SessionConnectorImpl.

remoting/webapp/crd/js/it2me_connect_flow.js

Index: remoting/webapp/crd/js/it2me_connect_flow.js
diff --git a/remoting/webapp/crd/js/it2me_connect_flow.js b/remoting/webapp/crd/js/it2me_connect_flow.js
new file mode 100644
index 0000000000000000000000000000000000000000..eb9ef5f4fbd8ed692d9842db6aa89775a6de7e78
--- /dev/null
+++ b/remoting/webapp/crd/js/it2me_connect_flow.js
@@ -0,0 +1,149 @@
+// Copyright 2015 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.
+
+/** @suppress {duplicate} */
+var remoting = remoting || {};
+
+(function() {
+
+'use strict';
+
+// Length of the various components of the access code in number of digits.
+var SUPPORT_ID_LENGTH = 7;
+var HOST_SECRET_LENGTH = 5;
+var ACCESS_CODE_LENGTH = SUPPORT_ID_LENGTH + HOST_SECRET_LENGTH;
+
+/**
+ * @param {remoting.SessionConnector} sessionConnector
+ * @constructor
+ * @private
+ */
+remoting.It2MeConnectFlow = function(sessionConnector) {
+  /** @private */
+  this.sessionConnector_ = sessionConnector;
+  /** @private */
+  this.hostId_ = '';
+  /** @private */
+  this.passCode_ = '';
+};
+
+/**
+ * Initiates an IT2Me connection.
+ *
+ * @param {remoting.SessionConnector} connector
+ * @param {string} accessCode
+ * @return {Promise} Promise that resolves when the connection is initiated.
+ *     Rejects with remoting.Error on failure.
+ */
+remoting.It2MeConnectFlow.start = function(connector, accessCode) {
+  var instance = new remoting.It2MeConnectFlow(connector);
+  return instance.connect_(accessCode);
+};
+
+/**
+ * @param {string} accessCode The access code as entered by the user.
+ * @return {Promise} Promise that resolves when the connection is initiated.
+ *     Rejects with remoting.Error on failure.
+ * @private
+ */
+remoting.It2MeConnectFlow.prototype.connect_ = function(accessCode) {
+  var that = this;
+
+  return this.verifyAccessCode_(accessCode).then(function() {
+    return remoting.identity.getToken();
+  }).then(function(/** string */ token) {
+    return that.getHostInfo_(token);
+  }).then(function(/** XMLHttpRequest */ xhr) {
+    return that.onHostInfo_(xhr);
+  }).then(function(/** remoting.Host */ host) {
+    that.sessionConnector_.connect(
+        remoting.DesktopConnectedView.Mode.IT2ME,
+        host,
+        new remoting.CredentialsProvider({ accessCode: that.passCode_ }));
+  }, function(error){

[garykac, 2015/03/06 23:53:01]

nit: I find that:
  }).then(function() {
  }).catch(function(error) {
  });

is easier to read than:
  }).then(function() {
  }, function(error) {
  });

Or rather, I find that the former makes the error-handling code more apparent
than the latter when scanning the code.

[Jamie, 2015/03/07 00:58:57]

+1, FWIW :)

+    return Promise.reject(/** remoting.Error */ error);
+  });
+};
+
+/**
+ * @param {string} accessCode
+ * @return {Promise}  Promise that resolves if the access code is valid.
+ * @private
+ */
+remoting.It2MeConnectFlow.prototype.verifyAccessCode_ = function(accessCode) {
+  var normalizedAccessCode = accessCode.replace(/\s/g, '');
+  if (normalizedAccessCode.length !== ACCESS_CODE_LENGTH) {
+    return Promise.reject(remoting.Error.INVALID_ACCESS_CODE);
+  }
+
+  this.hostId_ = normalizedAccessCode.substring(0, SUPPORT_ID_LENGTH);
+  this.passCode_ = normalizedAccessCode;
+
+  return Promise.resolve();
+};
+
+/**
+ * Continues an IT2Me connection once an access token has been obtained.
+ *
+ * @param {string} token An OAuth2 access token.
+ * @return {Promise<XMLHttpRequest>}
+ * @private
+ */
+remoting.It2MeConnectFlow.prototype.getHostInfo_ = function(token) {
+  var that = this;
+  return new Promise(function(resolve) {
+    remoting.xhr.start({
+      method: 'GET',
+      url: remoting.settings.DIRECTORY_API_BASE_URL + '/support-hosts/' +
+           encodeURIComponent(that.hostId_),
+      onDone: resolve,
+      oauthToken: token
+    });
+  });
+};
+
+/**
+ * Continues an IT2Me connection once the host JID has been looked up.
+ *
+ * @param {XMLHttpRequest} xhr The server response to the support-hosts query.
+ * @return {!Promise<!remoting.Host>} Rejects on error.
+ * @private
+ */
+remoting.It2MeConnectFlow.prototype.onHostInfo_ = function(xhr) {
+  if (xhr.status == 200) {
+    var response = /** @type {{data: {jabberId: string, publicKey: string}}} */
+        (base.jsonParseSafe(xhr.responseText));
+    if (response && response.data &&
+        response.data.jabberId && response.data.publicKey) {
+      var host = new remoting.Host();
+      host.hostId = this.hostId_;
+      host.jabberId = response.data.jabberId;
+      host.publicKey = response.data.publicKey;
+      host.hostName = response.data.jabberId.split('/')[0];
+      return Promise.resolve(host);
+    } else {
+      console.error('Invalid "support-hosts" response from server.');
+      return Promise.reject(remoting.Error.UNEXPECTED);
+    }
+  } else {
+    return Promise.reject(translateSupportHostsError(xhr.status));
+  }
+};
+
+/**
+ * @param {number} error An HTTP error code returned by the support-hosts
+ *     endpoint.
+ * @return {remoting.Error} The equivalent remoting.Error code.
+ */
+function translateSupportHostsError(error) {
+  switch (error) {
+    case 0: return remoting.Error.NETWORK_FAILURE;
+    case 404: return remoting.Error.INVALID_ACCESS_CODE;
+    case 502: // No break
+    case 503: return remoting.Error.SERVICE_UNAVAILABLE;
+    default: return remoting.Error.UNEXPECTED;
+  }
+}
+
+})();