Add the whispernet proxy.

chrome/browser/resources/whispernet_proxy/js/nacl.js

+// Copyright 2014 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.
+
+'use strict';
+
+/**
+ * Constructor for the Nacl bridge to the whispernet wrapper.
+ * @param {string} nmf The relative path to the nmf containing the location of
+ * the whispernet Nacl wrapper.
+ * @param {function()} readyCallback Callback to be called once we've loaded the
+ * whispernet wrapper.
+ */
+function NaclBridge(nmf, readyCallback) {
+  this.readyCallback_ = readyCallback;
+  this.callbacks_ = [];
+  this.isEnabled_ = false;
+  this.naclId_ = this.loadNacl_(nmf);
+}
+
+/**
+ * Method to send generic byte data to the whispernet wrapper.
+ * @param {string} data Raw data to send to the whispernet wrapper.
+ */
+NaclBridge.prototype.send = function(data) {
+  if (this.isEnabled_) {
+    this.embed_.postMessage(data);
+  } else {
+    console.error('Whisper Nacl Bridge not initialized!');
+  }
+};
+
+/**
+ * Method to add a listener to Nacl messages received by this bridge.
+ * @param {function(Event)} messageCallback Callback to receive the messsage.
+ */
+NaclBridge.prototype.addListener = function(messageCallback) {
+  this.callbacks_.push(messageCallback);
+};
+
+/**
+ * Method that receives Nacl messages and forwards them to registered
+ * callbacks.
+ * @param {Event} e Event from the whispernet wrapper.
+ * @private
+ */
+NaclBridge.prototype.onMessage_ = function(e) {
+  if (this.isEnabled_) {
+    this.callbacks_.forEach(function(callback) {
+      callback(e);
+    });
+  }
+};
+
+/**
+ * Injects the <embed> for this nacl manifest URL, generating a unique ID.
+ * @param {string} manifestUrl Url to the nacl manifest to load.
+ * @return {number} generated ID.
+ * @private
+ */
+NaclBridge.prototype.loadNacl_ = function(manifestUrl) {
+  var id = 'nacl-' + Math.floor(Math.random() * 10000);
+  this.embed_ = document.createElement('embed');
+  this.embed_.name = 'nacl_module';
+  this.embed_.width = 1;
+  this.embed_.height = 1;
+  this.embed_.src = manifestUrl;
+  this.embed_.id = id;
+  this.embed_.type = 'application/x-pnacl';
+
+  // Wait for the element to load and callback.
+  this.embed_.addEventListener('load', this.onNaclReady_.bind(this));
+  this.embed_.addEventListener('error', this.onNaclError_.bind(this));
+
+  // Inject the embed string into the page.
+  document.body.appendChild(this.embed_);
+
+  // Listen for messages from the NaCl module.
+  window.addEventListener('message', this.onMessage_.bind(this), true);
+  return id;
+};
+
+/**
+ * Callback that is called when the Whispernet wrapper is loaded and forward
+ * that status to the callback registered with us in the constructor.
+ * @private
+ */
+NaclBridge.prototype.onNaclReady_ = function() {
+  if (this.readyCallback_)
+    this.readyCallback_();
+  this.isEnabled_ = true;
+};
+
+/**
+ * Callback that handles Nacl errors.
+ * @param {string} msg Error string.
+ * @private
+ */
+NaclBridge.prototype.onNaclError_ = function(msg) {
+  // TODO(rkc): Handle error from NaCl better.
+  console.error('NaCl error', msg);
+};