Implement externally_connectable! Web pages can now communicate directly with

chrome/test/data/extensions/api_test/messaging/externally_connectable/sites/assertions.js

+// Copyright 2013 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.
+
+window.assertions = (function() {
+
+// Codes for test results. Must match ExternallyConnectableMessagingTest::Result
+// in c/b/extensions/extension_messages_apitest.cc.
+var results = {
+  OK: 0,
+  NAMESPACE_NOT_DEFINED: 1,
+  FUNCTION_NOT_DEFINED: 2,
+  COULD_NOT_ESTABLISH_CONNECTION_ERROR: 3,
+  OTHER_ERROR: 4,
+  INCORRECT_RESPONSE_SENDER: 5,
+  INCORRECT_RESPONSE_MESSAGE: 6
+};
+
+// Make the messages sent vaguely complex, but unambiguously JSON-ifiable.
+var message = [{'a': {'b': 10}}, 20, 'c\x10\x11'];
+
+function checkLastError(reply) {
+  if (!chrome.runtime.lastError)
+    return true;
+  var kCouldNotEstablishConnection =
+    'Could not establish connection. Receiving end does not exist.';
+  if (chrome.runtime.lastError.message == kCouldNotEstablishConnection)
+    reply(results.COULD_NOT_ESTABLISH_CONNECTION_ERROR);
+  else
+    reply(results.OTHER_ERROR);
+  return false;
+}
+
+function checkResponse(response, reply) {
+  // The response will be an echo of both the original message *and* the
+  // MessageSender (with the tab field stripped down).
+  //
+  // First check the sender was correct.
+  var incorrectSender = false;
+  if (!response.sender.hasOwnProperty('tab')) {
+    console.warn('Expected a tab, got none');
+    incorrectSender = true;
+  }
+  if (response.sender.tab.url != document.location.href) {
+    console.warn('Expected tab url ' + document.location.href + ' got ' +
+                 response.sender.tab.url);
+    incorrectSender = true;
+  }
+  if (response.sender.hasOwnProperty('id')) {
+    console.warn('Expected no id, got "' + response.sender.id + '"');
+    incorrectSender = true;
+  }
+  if (response.sender.url != document.location.href) {
+    console.warn('Expected url ' + document.location.href + ' got ' +
+                 response.sender.url);
+    incorrectSender = true;
+  }
+  if (incorrectSender) {
+    reply(results.INCORRECT_RESPONSE_SENDER);
+    return false;
+  }
+
+  // Check the correct content was echoed.
+  var expectedJson = JSON.stringify(message);
+  var actualJson = JSON.stringify(response.message);
+  if (actualJson == expectedJson)
+    return true;
+  console.warn('Expected message ' + expectedJson + ' got ' + actualJson);
+  reply(results.INCORRECT_RESPONSE_MESSAGE);
+  return false;
+}
+
+return {
+  canConnectAndSendMessages: function(extensionId) {
+    if (!chrome.runtime) {
+      reply(results.NAMESPACE_NOT_DEFINED);
+      return;
+    }
+
+    if (!chrome.runtime.sendMessage || !chrome.runtime.connect) {
+      reply(results.FUNCTION_NOT_DEFINED);
+      return;
+    }
+
+    function canSendMessage(reply) {
+      chrome.runtime.sendMessage(extensionId, message, function(response) {
+        if (checkLastError(reply) && checkResponse(response, reply))
+          reply(results.OK);
+      });
+    }
+
+    function canConnectAndSendMessages(reply) {
+      var port = chrome.runtime.connect(extensionId);
+      port.postMessage(message, function() {
+        checkLastError(reply);
+      });
+      port.postMessage(message, function() {
+        checkLastError(reply);
+      });
+      var pendingResponses = 2;
+      var ok = true;
+      port.onMessage.addListener(function(response) {
+        pendingResponses--;
+        ok = ok && checkLastError(reply) && checkResponse(response, reply);
+        if (pendingResponses == 0 && ok)
+          reply(results.OK);
+      });
+    }
+
+    var done = domAutomationController.send.bind(domAutomationController);
+    canSendMessage(function(result) {
+      if (result != results.OK)
+        done(result);
+      else
+        canConnectAndSendMessages(done);
+    });
+  },
+
+  isDefined: function(name) {
+    var result = results.OK;
+    if (!chrome.runtime)
+      result = results.NAMESPACE_NOT_DEFINED;
+    else if (!chrome.runtime[name])
+      result = results.FUNCTION_NOT_DEFINED;
+    domAutomationController.send(result);
+  }
+};
+
+}());  // window.assertions