[ServiceWorker] Add EmbeddedWorkerInstanceHost Interface.

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 <stdint.h>
 
 #include <memory>
 #include <string>
 
 #include "base/callback.h"
 #include "base/callback_forward.h"
 #include "base/gtest_prod_util.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "content/browser/service_worker/embedded_worker_status.h"
 #include "content/browser/service_worker/service_worker_metrics.h"
 #include "content/common/content_export.h"
 #include "content/common/service_worker/embedded_worker.mojom.h"
 #include "content/common/service_worker/service_worker_event_dispatcher.mojom.h"
 #include "content/common/service_worker/service_worker_status_code.h"
+#include "mojo/public/cpp/bindings/associated_binding.h"
 #include "url/gurl.h"
 
 // Windows headers will redefine SendMessage.
 #ifdef SendMessage
 #undef SendMessage
 #endif
 
 namespace IPC {
 class Message;
 }
 
 namespace content {
 
 class EmbeddedWorkerRegistry;
 struct EmbeddedWorkerStartParams;
 class ServiceWorkerContextCore;
 
 // This gives an interface to control one EmbeddedWorker instance, which
 // may be 'in-waiting' or running in one of the child processes added by
 // AddProcessReference().
-class CONTENT_EXPORT EmbeddedWorkerInstance {
+class CONTENT_EXPORT EmbeddedWorkerInstance
+    : NON_EXPORTED_BASE(public mojom::EmbeddedWorkerInstanceHost) {
  public:
   typedef base::Callback<void(ServiceWorkerStatusCode)> StatusCallback;
 
   // This enum is used in UMA histograms. Append-only.
   enum StartingPhase {
     NOT_STARTING,
     ALLOCATING_PROCESS,
     REGISTERING_TO_DEVTOOLS,
     SENT_START_WORKER,
     SCRIPT_DOWNLOADING,
@@ skipping 32 matching lines @@
                                    const GURL& source_url) {}
     virtual void OnReportConsoleMessage(int source_identifier,
                                         int message_level,
                                         const base::string16& message,
                                         int line_number,
                                         const GURL& source_url) {}
     // Returns false if the message is not handled by this listener.
     CONTENT_EXPORT virtual bool OnMessageReceived(const IPC::Message& message);
   };
 
-  ~EmbeddedWorkerInstance();
+  ~EmbeddedWorkerInstance() override;
 
   // Starts the worker. It is invalid to call this when the worker is not in
   // STOPPED status. |callback| is invoked after the worker script has been
   // started and evaluated, or when an error occurs.
   // |params| should be populated with service worker version info needed
   // to start the worker.
   void Start(std::unique_ptr<EmbeddedWorkerStartParams> params,
              mojom::ServiceWorkerEventDispatcherRequest dispatcher_request,
              const StatusCallback& callback);
 
@@ skipping 99 matching lines @@
                                      int worker_devtools_agent_route_id,
                                      bool wait_for_debugger);
 
   // Sends StartWorker message via Mojo.
   ServiceWorkerStatusCode SendStartWorker(
       std::unique_ptr<EmbeddedWorkerStartParams> params);
 
   // Called back from StartTask after a start worker message is sent.
   void OnStartWorkerMessageSent();
 
-  // Called back from Registry when the worker instance has ack'ed that
+  // Implements mojom::EmbeddedWorkerInstanceHost.
+  // Be called when the worker instance has ack'ed that

[kinuko, 2017/04/11 14:03:17]

nit: 'Called' seems to be more common than 'Be called' in SW code base?

Also: we prefer descriptive comments rather than imperative ones for function
declarations, so if we change this 'Gets called' is probably preferable

https://google.github.io/styleguide/cppguide.html#Comments

[falken, 2017/04/11 14:10:05]

I'm thinking we should move all these comments to the mojom file. Generally, the
mojo interface should be a well-documented interface that the C++ class
implements. Then almost all that's needed here is
"mojom::EmbeddedWorkerInstanceHost implementation". We also would have less
duplicated comments.

What would belong here are implementation details only like:
"This will change the internal status from STARTING to RUNNING."

[kinuko, 2017/04/12 00:49:44]

Yeah I agree, SGTM

[leonhsl(Using Gerrit), 2017/04/12 03:34:03]

I see, and agree that we should document mojom file well and add comments about
impl details in C++ header file. Will update.

[leonhsl(Using Gerrit), 2017/04/12 12:32:12]

Done.

   // it is ready for inspection.
-  void OnReadyForInspection();
-
-  // Called back from Registry when the worker instance has ack'ed that
+  void OnReadyForInspection() override;
+  // Be called when the worker instance has ack'ed that
   // it finished loading the script.
-  void OnScriptLoaded();
-
-  // Called back from Registry when the worker instance has ack'ed that
+  void OnScriptLoaded() override;
+  // Be called when the worker instance has ack'ed that
   // it has started a worker thread.
-  void OnThreadStarted(int thread_id);
-
-  // Called back from Registry when the worker instance has ack'ed that
+  void OnThreadStarted(int thread_id, int provider_id) override;
+  // Be called when the worker instance has ack'ed that
   // it failed to load the script.
-  void OnScriptLoadFailed();
-
-  // Called back from Registry when the worker instance has ack'ed that
+  void OnScriptLoadFailed() override;
+  // Be called when the worker instance has ack'ed that
   // it finished evaluating the script. This is called before OnStarted.
-  void OnScriptEvaluated(bool success);
-
-  // Called back from Registry when the worker instance has ack'ed that its
+  void OnScriptEvaluated(bool success) override;
+  // Be called when the worker instance has ack'ed that
   // WorkerGlobalScope has actually started and evaluated the script. This is
   // called after OnScriptEvaluated.
   // This will change the internal status from STARTING to RUNNING.
-  void OnStarted();
-
-  // Called back from Registry when the worker instance has ack'ed that
+  void OnStarted() override;
+  // Be called 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();
+  void OnStopped() override;
+  // Be called when the worker instance reports the exception.
+  void OnReportException(const base::string16& error_message,
+                         int line_number,
+                         int column_number,
+                         const GURL& source_url) override;
+  // Be called when the worker instance reports to the console.
+  void OnReportConsoleMessage(int source_identifier,
+                              int message_level,
+                              const base::string16& message,
+                              int line_number,
+                              const GURL& source_url) override;
 
   // Called when ServiceWorkerDispatcherHost for the worker died while it was
   // running.
   void OnDetached();
 
   // Called back from Registry when the worker instance sends message
   // to the browser (i.e. EmbeddedWorker observers).
   // Returns false if the message is not handled.
   bool OnMessageReceived(const IPC::Message& message);
 
-  // Called back from Registry when the worker instance reports the exception.
-  void OnReportException(const base::string16& error_message,
-                         int line_number,
-                         int column_number,
-                         const GURL& source_url);
-
-  // Called back from Registry when the worker instance reports to the console.
-  void OnReportConsoleMessage(int source_identifier,
-                              int message_level,
-                              const base::string16& message,
-                              int line_number,
-                              const GURL& source_url);
-
   // Resets all running state. After this function is called, |status_| is
   // STOPPED.
   void ReleaseProcess();
 
   // Called back from StartTask when the startup sequence failed. Calls
   // ReleaseProcess() and invokes |callback| with |status|. May destroy |this|.
   void OnStartFailed(const StatusCallback& callback,
                      ServiceWorkerStatusCode status);
 
   // Returns the time elapsed since |step_time_| and updates |step_time_|
@@ skipping 10 matching lines @@
   StartingPhase starting_phase_;
   int restart_count_;
 
   // Current running information.
   std::unique_ptr<EmbeddedWorkerInstance::WorkerProcessHandle> process_handle_;
   int thread_id_;
 
   // |client_| is used to send messages to the renderer process.
   mojom::EmbeddedWorkerInstanceClientPtr client_;
 
+  // Binding for EmbeddedWorkerInstanceHost, runs on IO thread.
+  mojo::AssociatedBinding<EmbeddedWorkerInstanceHost> instance_host_binding_;
+
   // TODO(shimazu): Remove this after EmbeddedWorkerStartParams is changed to
   // a mojo struct.
   mojom::ServiceWorkerEventDispatcherRequest pending_dispatcher_request_;
 
   // Whether devtools is attached or not.
   bool devtools_attached_;
 
   // True if the script load request accessed the network. If the script was
   // served from HTTPCache or ServiceWorkerDatabase this value is false.
   bool network_accessed_for_script_;
@@ skipping 11 matching lines @@
   base::TimeTicks step_time_;
 
   base::WeakPtrFactory<EmbeddedWorkerInstance> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EmbeddedWorkerInstance);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_EMBEDDED_WORKER_INSTANCE_H_