Implement ServiceWorkerVersion::SendMessage() (for dispatching events etc)

content/browser/service_worker/embedded_worker_instance.h

 // 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.
 
 #ifndef CONTENT_BROWSER_SERVICE_WORKER_EMBEDDED_WORKER_INSTANCE_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_EMBEDDED_WORKER_INSTANCE_H_
 
 #include <map>
 
 #include "base/basictypes.h"
@@ skipping 26 matching lines @@
     STARTING,
     RUNNING,
     STOPPING,
   };
 
   class Observer {
    public:
     virtual ~Observer() {}
     virtual void OnStarted() = 0;
     virtual void OnStopped() = 0;
-    virtual void OnMessageReceived(const IPC::Message& message) = 0;
+    virtual void OnMessageReceived(int request_id,
+                                   const IPC::Message& message) = 0;
   };
 
   ~EmbeddedWorkerInstance();
 
   // Starts the worker. It is invalid to call this when the worker is
   // not in STOPPED status.
   ServiceWorkerStatusCode Start(int64 service_worker_version_id,
                                 const GURL& script_url);
 
   // Stops the worker. It is invalid to call this when the worker is
   // not in STARTING or RUNNING status.
   // This returns false if stopping a worker fails immediately, e.g. when
   // IPC couldn't be sent to the worker.
   ServiceWorkerStatusCode Stop();
 
   // Sends |message| to the embedded worker running in the child process.
   // It is invalid to call this while the worker is not in RUNNING status.
-  ServiceWorkerStatusCode SendMessage(const IPC::Message& message);
+  // |request_id| can be optionally used to establish 2-way request-response
+  // messaging (e.g. the receiver can send back a response using the same
+  // request_id).
+  ServiceWorkerStatusCode SendMessage(
+      int request_id, const IPC::Message& message);
 
   // Add or remove |process_id| to the internal process set where this
   // worker can be started.
   void AddProcessReference(int process_id);
   void ReleaseProcessReference(int process_id);
 
   int embedded_worker_id() const { return embedded_worker_id_; }
   Status status() const { return status_; }
   int process_id() const { return process_id_; }
   int thread_id() const { return thread_id_; }
@@ skipping 19 matching lines @@
   void OnStarted(int thread_id);
 
   // Called back from Registry when the worker instance has ack'ed that
   // its WorkerGlobalScope is actually stopped in the child process.
   // This will change the internal status from STARTING or RUNNING to
   // STOPPED.
   void OnStopped();
 
   // Called back from Registry when the worker instance sends message
   // to the browser (i.e. EmbeddedWorker observers).
-  void OnMessageReceived(const IPC::Message& message);
+  void OnMessageReceived(int request_id, const IPC::Message& message);
 
   // Chooses a process to start this worker and populate process_id_.
   // Returns false when no process is available.
   bool ChooseProcess();
 
   scoped_refptr<EmbeddedWorkerRegistry> registry_;
   const int embedded_worker_id_;
   Status status_;
 
   // Current running information. -1 indicates the worker is not running.
   int process_id_;
   int thread_id_;
 
   ProcessRefMap process_refs_;
   ObserverList<Observer> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(EmbeddedWorkerInstance);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_EMBEDDED_WORKER_INSTANCE_H_