Implement a module system for the extension bindings JS.

chrome/renderer/extensions/chrome_v8_extension.h

 // 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.
 
 #ifndef CHROME_RENDERER_EXTENSIONS_CHROME_V8_EXTENSION_H_
 #define CHROME_RENDERER_EXTENSIONS_CHROME_V8_EXTENSION_H_
 #pragma once
 
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
 #include "base/string_piece.h"
 #include "chrome/renderer/extensions/chrome_v8_extension_handler.h"
 #include "v8/include/v8.h"
 
 #include <map>
 #include <set>
 #include <string>
 
 class ChromeV8Context;
 class Extension;
 class ExtensionDispatcher;
 
 namespace content {
 class RenderView;
 }
 
 // This is a base class for chrome extension bindings.  Common features that
 // are shared by different modules go here.
 class ChromeV8Extension : public v8::Extension {

[Aaron Boodman, 2012/02/16 01:54:42]

The inheritance on v8::Extension no longer makes sense.

[Aaron Boodman, 2012/02/16 01:54:42]

Now that this is no longer inheriting from v8::Extension, it makes even less
sense to have the conflicting name. Could we rename it Binding or something?

[koz (OOO until 15th September), 2012/02/27 01:06:14]

I've added a TODO for this.

  public:
   typedef std::set<ChromeV8Extension*> InstanceSet;
   static const InstanceSet& GetAll();
 
   ChromeV8Extension(const char* name,
                     int resource_id,
                     ExtensionDispatcher* extension_dispatcher);
   ChromeV8Extension(const char* name,

[Aaron Boodman, 2012/02/16 01:54:42]

Do we still use the name and dependency params?

[koz (OOO until 15th September), 2012/02/27 01:06:14]

Removed.

                     int resource_id,
                     int dependency_count,
                     const char** dependencies,
                     ExtensionDispatcher* extension_dispatcher);
   virtual ~ChromeV8Extension();
 
   ExtensionDispatcher* extension_dispatcher() { return extension_dispatcher_; }
 
   void ContextWillBeReleased(ChromeV8Context* context);

[Aaron Boodman, 2012/02/16 01:54:42]

This might no longer be needed.

[koz (OOO until 15th September), 2012/02/27 01:06:14]

Removed.

 
-  // Derived classes should call this at the end of their implementation in
-  // order to expose common native functions, like GetChromeHidden, to the
-  // v8 extension.
-  virtual v8::Handle<v8::FunctionTemplate>
-      GetNativeFunction(v8::Handle<v8::String> name) OVERRIDE;
+  // Derived classes should override this to set up named functions on
+  // |object|.
+  virtual void SetNativeFunctions(v8::Handle<v8::Object> object) {}
 
  protected:
   template<class T>
   static T* GetFromArguments(const v8::Arguments& args) {
     CHECK(!args.Data().IsEmpty());
     T* result = static_cast<T*>(args.Data().As<v8::External>()->Value());
     return result;
   }
 
+  static v8::Handle<v8::Value> Router(const v8::Arguments& args);

[Aaron Boodman, 2012/02/16 01:54:42]

This should not be exposed as interface. It can be in an anonymous namespace in
the cc file.

[koz (OOO until 15th September), 2012/02/27 01:06:14]

Done.

+
   // Gets the render view for the current v8 context.
   static content::RenderView* GetCurrentRenderView();
 
   // Note: do not call this function before or during the chromeHidden.onLoad
   // event dispatch. The URL might not have been committed yet and might not
   // be an extension URL.
   const ::Extension* GetExtensionForCurrentRenderView() const;
 
   // Checks that the current context contains an extension that has permission
   // to execute the specified function. If it does not, a v8 exception is thrown
   // and the method returns false. Otherwise returns true.
   bool CheckCurrentContextAccessToExtensionAPI(
       const std::string& function_name) const;
 
-  // Create a handler for |context|. If a subclass of ChromeV8Extension wishes
-  // to support handlers, it should override this.
-  virtual ChromeV8ExtensionHandler* CreateHandler(ChromeV8Context* context);
+  // Handle a native function call from JavaScript.
+  virtual v8::Handle<v8::Value> HandleNativeFunction(
+      const std::string& function_name, const v8::Arguments& args);
 
-  // Returns the chromeHidden object for the current context.
-  static v8::Handle<v8::Value> GetChromeHidden(const v8::Arguments& args);
+  // Causes the object to set a function named |name| on |object| that gets
+  // handled by HandleNativeFunction().
+  void RouteFunctionHere(const char* name, v8::Handle<v8::Object> object);

[Aaron Boodman, 2012/02/16 01:54:42]

I think something like AddNativeFunction would be a more clear name. Also the
params seem more naturally ordered: object, name, handler.

+
+  typedef v8::Handle<v8::Value> (*HandlerFunction)(const v8::Arguments& args);
+  // Causes the object to set |function| on |object| with name |name|.
+  void RouteFunctionToStatic(const char* name, HandlerFunction function,
+      v8::Handle<v8::Object> object);
 
   ExtensionDispatcher* extension_dispatcher_;
 
  private:
   static base::StringPiece GetStringResource(int resource_id);
 
-  // Helper to print from bindings javascript.
-  static v8::Handle<v8::Value> Print(const v8::Arguments& args);
-
-  // Handle a native function call from JavaScript.
-  static v8::Handle<v8::Value> HandleNativeFunction(const v8::Arguments& args);
-
-  // Get the handler instance for |context|, or NULL if no such context exists.
-  ChromeV8ExtensionHandler* GetHandler(ChromeV8Context* context) const;
-
-  // Map of all current handlers.
-  typedef std::map<ChromeV8Context*,
-                   linked_ptr<ChromeV8ExtensionHandler> > HandlerMap;
-  HandlerMap handlers_;
-
   DISALLOW_COPY_AND_ASSIGN(ChromeV8Extension);
 };
 
 #endif  // CHROME_RENDERER_EXTENSIONS_CHROME_V8_EXTENSION_H_