Add interface versioning. Methods queryVersion and requireVersion.

mojo/public/js/lib/control_message_proxy.js

+// Copyright 2017 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.
+
+define("mojo/public/js/lib/control_message_proxy", [
+  "mojo/public/interfaces/bindings/interface_control_messages.mojom",
+  "mojo/public/js/validator",
+  "mojo/public/js/codec",
+], function(interfaceCtrlMsgs, validator, codec) {
+
+  function sendRunOrClosePipeMessage(receiver, runOrClosePipeMsgParams) {
+    var messageName = interfaceCtrlMsgs.kRunOrClosePipeMessageId;
+    var payloadSize = interfaceCtrlMsgs.RunOrClosePipeMessageParams
+                                              .encodedSize;
+    var builder = new codec.MessageBuilder(messageName, payloadSize);
+    builder.encodeStruct(interfaceCtrlMsgs.RunOrClosePipeMessageParams,
+                         runOrClosePipeMsgParams);
+    var message = builder.finish();
+    receiver.accept(message);
+  }
+
+  function validateControlResponse(message){
+    var error = validator.validateMessageIsResponse(message);
+    if (error != validator.validationError.None) {
+      throw error;
+    }
+
+    if (!message.getName() &&
+        message.getName() != interfaceCtrlMsgs.kRunMessageId) {
+      throw new Error(`Control message name is not
+                       interfaceCtrlMsgs.kRunMessageId`);
+    }
+  }
+
+  function runResponseForwardAccept(message) {
+    validateControlResponse(message);
+
+    var reader = new codec.MessageReader(message);
+    var runResponseMessageParams = reader.decodeStruct(
+        interfaceCtrlMsgs.RunResponseMessageParams);
+
+    return Promise.resolve(runResponseMessageParams);
+  }
+
+ /**
+  * Sends the given run message through the receiver.
+  * @param  {Router} receiver.
+  * @param  {RunMessageParams} runMessageParams.
+  * @return {Promise}
+  */
+  function sendRunMessage(receiver, runMessageParams) {
+    var messageName = interfaceCtrlMsgs.kRunMessageId;
+    var payloadSize = interfaceCtrlMsgs.RunMessageParams.encodedSize;
+    var builder = new codec.MessageBuilder(messageName, payloadSize);
+    builder.encodeStruct(interfaceCtrlMsgs.RunMessageParams,
+                         runMessageParams);
+    var message = builder.finish();
+
+    return receiver.acceptAndExpectResponse(message).then(

[wangjimmy, 2017/02/04 01:32:42]

Router.js 's acceptAndExpectResponse never resolves. Run mojo_js_unittests,
JSTest.InterfacePtr. To see queryVersion get called and which calls this method.

+      runResponseForwardAccept);
+  }
+
+  function runVersion(runResponseMessageParams) {
+    if (runResponseMessageParams.output &&
+      runResponseMessageParams.output.tag ==
+      interfaceCtrlMsgs.RunOutput.Tags.query_version_result) {
+    var version = runResponseMessageParams.output
+                                          .query_version_result
+                                          .version;
+    return version;
+    }
+  }
+
+  function ControlMessageProxy() {
+    this.receiver = null;
+  }
+
+  ControlMessageProxy.prototype.queryVersion = function queryVersion() {
+    var runMessageParams = new interfaceCtrlMsgs.RunMessageParams();
+    runMessageParams.input = new interfaceCtrlMsgs.RunInput();
+    runMessageParams.input.query_version = new
+      interfaceCtrlMsgs.QueryVersion();
+
+    return sendRunMessage(this.receiver, runMessageParams).then(runVersion);
+  };
+
+  ControlMessageProxy.prototype.requireVersion = function
+    requireVersion(version) {
+
+    var runOrClosePipeMsgParams = new
+      interfaceCtrlMsgs.RunOrClosePipeMessageParams();
+    runOrClosePipeMsgParams.input = new interfaceCtrlMsgs.RunOrClosePipeInput();
+    runOrClosePipeMsgParams.input.require_version = new
+      interfaceCtrlMsgs.RequireVersion({'version': version});
+    sendRunOrClosePipeMessage(this.receiver, runOrClosePipeMsgParams);
+  };
+
+  var exports = {};
+  exports.ControlMessageProxy = ControlMessageProxy;
+
+  return exports;
+});