Mojo: Use InterfaceFactory<Interface> for service registration

mojo/public/cpp/application/application_connection.h

 // Copyright 2014 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 MOJO_PUBLIC_APPLICATION_APPLICATION_CONNECTION_H_
 #define MOJO_PUBLIC_APPLICATION_APPLICATION_CONNECTION_H_
 
 #include <string>
 
+#include "mojo/public/cpp/application/interface_factory.h"
 #include "mojo/public/cpp/application/lib/service_connector.h"
 
 namespace mojo {
 
 // An instance of this class is passed to
 // ApplicationDelegate's ConfigureIncomingConnection() method each time a
 // connection is made to this app, and to ApplicationDelegate's
 // ConfigureOutgoingConnection() method when the app connects to
 // another.
 //
 // To use define a class that implements your specific service api, e.g. FooImpl
 // to implement a service named Foo.
 // That class must subclass an InterfaceImpl specialization.
 //
-// If there is context that is to be shared amongst all instances, define a
-// constructor with that class as its only argument, otherwise define an empty
-// constructor.
+// Then implement an InterfaceFactory<Foo> that binds instances of FooImpl to
+// InterfaceRequest<Foo>s and register that on the connection.
 //
-// class FooImpl : public InterfaceImpl<Foo> {
-//  public:
-//   explicit FooImpl(ApplicationConnnection* connection) {}
-// };
+// connection->AddServiceFactory(&factory);
 //
-// or
+// Or if you have multiple factories implemented by the same type, explicitly
+// specify the interface to register the factory for:
 //
-// class BarImpl : public InterfaceImpl<Bar> {
-//  public:
-//   // contexts will remain valid for the lifetime of BarImpl.
-//   BarImpl(ApplicationConnnection* connection, BarContext* service_context)
-//          : connection_(connection), servicecontext_(context) {}
+// connection->AddServiceFactory<Foo>(&my_foo_and_bar_factory_);
+// connection->AddServiceFactory<Bar>(&my_foo_and_bar_factory_);
 //
-// Create an ApplicationDelegate instance and pass it to the constructor
-// of an ApplicationImpl. The delegate will be called when new connections are
-// made to other applications.
-//
-// connection->AddService<FooImpl>();
-//
-// BarContext context;
-// connection->AddService<BarImpl>(&context);
+// The InterfaceFactory must outlive the ApplicationConnection.

[tim (not reviewing), 2014/07/16 17:57:09]

I'm a bit confused here. I don't see any changes to ServiceRegistry in this
patch, which means that the ServiceConnectorBase that is passed to
AddServiceConnector is actually *owned* by the ApplicationConnection.

[jamesr, 2014/07/17 22:22:50]

Right, and the service connector maintains a raw pointer to the
InterfaceFactory.  Thus the InterfaceFactory has to live at least as long as the
ApplicationConnection.  If we need a way to have the InterfaceFactory die first
then it needs to somehow make sure that the ApplicationConnection does not
retain a raw pointer to it (i.e. add a RemoveService() or something like that).

 class ApplicationConnection {
  public:
   virtual ~ApplicationConnection();
 
-  // Impl’s constructor will receive two arguments:
-  // Impl::Impl(Application::Context* app_context,
-  //            ServiceContext* svc_context)
-  template <typename Impl, typename ServiceContext>
-  void AddService(ServiceContext* context) {
+  template <typename Interface>
+  void AddServiceFactory(InterfaceFactory<Interface>* factory) {
     AddServiceConnector(
-        new internal::ServiceConnector<Impl, ServiceContext>(Impl::Name_,
-                                                             context));
-  }
-
-  // Impl’s constructor will receive one argument:
-  // Impl::Impl(Application::Context* app_context)
-  template <typename Impl>
-  void AddService() {
-    AddServiceConnector(
-        new internal::ServiceConnector<Impl, void>(Impl::Name_, NULL));
+        new internal::InterfaceFactoryConnector<Interface>(factory));
   }
 
   // Connect to the service implementing |Interface|.
   template <typename Interface>
   void ConnectToService(InterfacePtr<Interface>* ptr) {
     MessagePipe pipe;
     ptr->Bind(pipe.handle0.Pass());
     GetServiceProvider()->ConnectToService(Interface::Name_,
                                            pipe.handle1.Pass());
   }
@@ skipping 18 matching lines @@
   virtual ServiceProvider* GetServiceProvider() = 0;
 
 private:
  virtual void AddServiceConnector(
       internal::ServiceConnectorBase* service_connector) = 0;
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_APPLICATION_APPLICATION_CONNECTION_H_