Native Messaging!

chrome/renderer/resources/extensions/extension_custom_bindings.js

 // Copyright (c) 2012 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.
 
 // Custom bindings for the extension API.
 
 var extensionNatives = requireNative('extension');
 var GetExtensionViews = extensionNatives.GetExtensionViews;
 var OpenChannelToExtension = extensionNatives.OpenChannelToExtension;
+var OpenChannelToNativeApp = extensionNatives.OpenChannelToNativeApp;
 
 var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
 
 var inIncognitoContext = requireNative('process').InIncognitoContext();
 
 chrome.extension = chrome.extension || {};
 
 var manifestVersion = requireNative('process').GetManifestVersion();
 if (manifestVersion < 2) {
   chrome.self = chrome.extension;
@@ skipping 66 matching lines @@
       targetId = args[lastArg--];
 
     if (lastArg != -1)
       throw new Error('Invalid arguments to ' + functionName + '.');
     return [targetId, request, responseCallback];
   }
   apiFunctions.setUpdateArgumentsPreValidate('sendRequest',
       sendMessageUpdateArguments.bind(null, 'sendRequest'));
   apiFunctions.setUpdateArgumentsPreValidate('sendMessage',
       sendMessageUpdateArguments.bind(null, 'sendMessage'));
+  apiFunctions.setUpdateArgumentsPreValidate('sendNativeMessage',
+      sendMessageUpdateArguments.bind(null, 'sendNativeMessage'));
 
   apiFunctions.setHandleRequest('sendRequest',
                                 function(targetId, request, responseCallback) {
     var port = chrome.extension.connect(targetId || extensionId,
                                         {name: chromeHidden.kRequestChannel});
     chromeHidden.Port.sendMessageImpl(port, request, responseCallback);
   });
 
   apiFunctions.setHandleRequest('sendMessage',
                                 function(targetId, message, responseCallback) {
     var port = chrome.extension.connect(targetId || extensionId,
                                         {name: chromeHidden.kMessageChannel});
     chromeHidden.Port.sendMessageImpl(port, message, responseCallback);
   });
 
-  apiFunctions.setUpdateArgumentsPreValidate('connect', function() {
+  apiFunctions.setHandleRequest('sendNativeMessage',
+                                function(targetId, message, responseCallback) {
+    var port = chrome.extension.connectNative(targetId,
+        {name: chromeHidden.kNativeMessageChannel,
+         message: message});
+    // TODO(eriq): Properly handle the callback like in sendMessageImpl()

[Matt Perry, 2012/08/09 02:13:00]

can you just use sendMessageImpl directly?

[eaugusti, 2012/08/13 23:22:34]

Yes, but it it counter-intuitive since we don't want to actually send another
message. I think the decision here is dependent upon the decision we make to
your earlier comment with the four primitives. For now, I will just use it.

+    port.onMessage.addListener(function(response) {
+      try {
+        responseCallback(response);
+      } finally {
+        port.disconnect();
+        port = null;
+      }
+    });
+  });
+
+  function connectUpdateArguments(functionName) {
     // Align missing (optional) function arguments with the arguments that
     // schema validation is expecting, e.g.
     //   extension.connect()   -> extension.connect(null, null)
     //   extension.connect({}) -> extension.connect(null, {})
-    var nextArg = 0;
+    var nextArg = 1;  // skip functionName
 
     // targetId (first argument) is optional.
     var targetId = null;
     if (typeof(arguments[nextArg]) == 'string')
       targetId = arguments[nextArg++];
 
     // connectInfo (second argument) is optional.
     var connectInfo = null;
     if (typeof(arguments[nextArg]) == 'object')
       connectInfo = arguments[nextArg++];
 
     if (nextArg != arguments.length)
-      throw new Error('Invalid arguments to connect');
+      throw new Error('Invalid arguments to ' + functionName + '.');
+
+    if (functionName == 'connectNative') {
+      connectInfo = {name: connectInfo.name || functionName,
+                     message: connectInfo.message || connectInfo};
+    }
     return [targetId, connectInfo];
-  });
+  }
+
+  apiFunctions.setUpdateArgumentsPreValidate('connect',
+    connectUpdateArguments.bind(null, 'connect'));
+  apiFunctions.setUpdateArgumentsPreValidate('connectNative',
+    connectUpdateArguments.bind(null, 'connectNative'));
 
   apiFunctions.setHandleRequest('connect', function(targetId, connectInfo) {
     if (!targetId)
       targetId = extensionId;
     var name = '';
     if (connectInfo && connectInfo.name)
       name = connectInfo.name;
 
     var portId = OpenChannelToExtension(extensionId, targetId, name);
     if (portId >= 0)
       return chromeHidden.Port.createPort(portId, name);
     throw new Error('Error connecting to extension ' + targetId);
   });
+
+  apiFunctions.setHandleRequest('connectNative',
+                                function(nativeAppName, connectInfo) {
+    if (!nativeAppName)
+      throw new Error('Need native app name');
+
+    if (!connectInfo || !connectInfo.name)
+      throw new Error('Need a name for native connect');
+
+    if (!connectInfo.message)
+      throw new Error('Need a message for native connect');

[Matt Perry, 2012/08/09 02:13:00]

I think you can use the schema validation for these checks.

[eaugusti, 2012/08/13 23:22:34]

Done.

+
+    // Turn the object into a string here, because it eventually will be.
+    var portId = OpenChannelToNativeApp(extensionId,
+                                        nativeAppName,
+                                        connectInfo.name,
+                                        JSON.stringify(connectInfo.message));
+    if (portId >= 0) {
+      return chromeHidden.Port.createPort(portId, connectInfo.name);
+    }
+    throw new Error('Error connecting to native app: ' + nativeAppName);
+  });
 });