| // 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 EXTENSIONS_RENDERER_MODULE_SYSTEM_H_ |
| #define EXTENSIONS_RENDERER_MODULE_SYSTEM_H_ |
| |
| #include <map> |
| #include <set> |
| #include <string> |
| #include <vector> |
| |
| #include "base/compiler_specific.h" |
| #include "base/memory/linked_ptr.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "extensions/renderer/native_handler.h" |
| #include "extensions/renderer/object_backed_native_handler.h" |
| #include "v8/include/v8.h" |
| |
| namespace extensions { |
| |
| class ScriptContext; |
| |
| // A module system for JS similar to node.js' require() function. |
| // Each module has three variables in the global scope: |
| // - exports, an object returned to dependencies who require() this |
| // module. |
| // - require, a function that takes a module name as an argument and returns |
| // that module's exports object. |
| // - requireNative, a function that takes the name of a registered |
| // NativeHandler and returns an object that contains the functions the |
| // NativeHandler defines. |
| // |
| // Each module in a ModuleSystem is executed at most once and its exports |
| // object cached. |
| // |
| // Note that a ModuleSystem must be used only in conjunction with a single |
| // v8::Context. |
| // TODO(koz): Rename this to JavaScriptModuleSystem. |
| class ModuleSystem : public ObjectBackedNativeHandler { |
| public: |
| class SourceMap { |
| public: |
| virtual ~SourceMap() {} |
| virtual v8::Handle<v8::Value> GetSource(v8::Isolate* isolate, |
| const std::string& name) = 0; |
| virtual bool Contains(const std::string& name) = 0; |
| }; |
| |
| class ExceptionHandler { |
| public: |
| virtual ~ExceptionHandler() {} |
| virtual void HandleUncaughtException(const v8::TryCatch& try_catch) = 0; |
| |
| protected: |
| // Formats |try_catch| as a nice string. |
| std::string CreateExceptionString(const v8::TryCatch& try_catch); |
| }; |
| |
| // Enables native bindings for the duration of its lifetime. |
| class NativesEnabledScope { |
| public: |
| explicit NativesEnabledScope(ModuleSystem* module_system); |
| ~NativesEnabledScope(); |
| |
| private: |
| ModuleSystem* module_system_; |
| DISALLOW_COPY_AND_ASSIGN(NativesEnabledScope); |
| }; |
| |
| // |source_map| is a weak pointer. |
| ModuleSystem(ScriptContext* context, SourceMap* source_map); |
| virtual ~ModuleSystem(); |
| |
| // Require the specified module. This is the equivalent of calling |
| // require('module_name') from the loaded JS files. |
| v8::Handle<v8::Value> Require(const std::string& module_name); |
| void Require(const v8::FunctionCallbackInfo<v8::Value>& args); |
| |
| // Run |code| in the current context with the name |name| used for stack |
| // traces. |
| v8::Handle<v8::Value> RunString(v8::Handle<v8::String> code, |
| v8::Handle<v8::String> name); |
| |
| // Calls the specified method exported by the specified module. This is |
| // equivalent to calling require('module_name').method_name() from JS. |
| v8::Local<v8::Value> CallModuleMethod(const std::string& module_name, |
| const std::string& method_name); |
| v8::Local<v8::Value> CallModuleMethod( |
| const std::string& module_name, |
| const std::string& method_name, |
| std::vector<v8::Handle<v8::Value> >* args); |
| v8::Local<v8::Value> CallModuleMethod(const std::string& module_name, |
| const std::string& method_name, |
| int argc, |
| v8::Handle<v8::Value> argv[]); |
| |
| // Register |native_handler| as a potential target for requireNative(), so |
| // calls to requireNative(|name|) from JS will return a new object created by |
| // |native_handler|. |
| void RegisterNativeHandler(const std::string& name, |
| scoped_ptr<NativeHandler> native_handler); |
| |
| // Causes requireNative(|name|) to look for its module in |source_map_| |
| // instead of using a registered native handler. This can be used in unit |
| // tests to mock out native modules. |
| void OverrideNativeHandlerForTest(const std::string& name); |
| |
| // Executes |code| in the current context with |name| as the filename. |
| void RunString(const std::string& code, const std::string& name); |
| |
| // Make |object|.|field| lazily evaluate to the result of |
| // require(|module_name|)[|module_field|]. |
| // |
| // TODO(kalman): All targets for this method are ObjectBackedNativeHandlers, |
| // move this logic into those classes (in fact, the chrome |
| // object is the only client, only that needs to implement it). |
| void SetLazyField(v8::Handle<v8::Object> object, |
| const std::string& field, |
| const std::string& module_name, |
| const std::string& module_field); |
| |
| void SetLazyField(v8::Handle<v8::Object> object, |
| const std::string& field, |
| const std::string& module_name, |
| const std::string& module_field, |
| v8::AccessorGetterCallback getter); |
| |
| // Make |object|.|field| lazily evaluate to the result of |
| // requireNative(|module_name|)[|module_field|]. |
| // TODO(kalman): Same as above. |
| void SetNativeLazyField(v8::Handle<v8::Object> object, |
| const std::string& field, |
| const std::string& module_name, |
| const std::string& module_field); |
| |
| // Passes exceptions to |handler| rather than console::Fatal. |
| void SetExceptionHandlerForTest(scoped_ptr<ExceptionHandler> handler) { |
| exception_handler_ = handler.Pass(); |
| } |
| |
| protected: |
| friend class ScriptContext; |
| virtual void Invalidate() OVERRIDE; |
| |
| private: |
| typedef std::map<std::string, linked_ptr<NativeHandler> > NativeHandlerMap; |
| |
| // Retrieves the lazily defined field specified by |property|. |
| static void LazyFieldGetter(v8::Local<v8::String> property, |
| const v8::PropertyCallbackInfo<v8::Value>& info); |
| // Retrieves the lazily defined field specified by |property| on a native |
| // object. |
| static void NativeLazyFieldGetter( |
| v8::Local<v8::String> property, |
| const v8::PropertyCallbackInfo<v8::Value>& info); |
| |
| // Called when an exception is thrown but not caught. |
| void HandleException(const v8::TryCatch& try_catch); |
| |
| // Ensure that require_ has been evaluated from require.js. |
| void EnsureRequireLoaded(); |
| |
| void RequireForJs(const v8::FunctionCallbackInfo<v8::Value>& args); |
| v8::Local<v8::Value> RequireForJsInner(v8::Handle<v8::String> module_name); |
| |
| typedef v8::Handle<v8::Value>(ModuleSystem::*RequireFunction)( |
| const std::string&); |
| // Base implementation of a LazyFieldGetter which uses |require_fn| to require |
| // modules. |
| static void LazyFieldGetterInner( |
| v8::Local<v8::String> property, |
| const v8::PropertyCallbackInfo<v8::Value>& info, |
| RequireFunction require_function); |
| |
| // Return the named source file stored in the source map. |
| // |args[0]| - the name of a source file in source_map_. |
| v8::Handle<v8::Value> GetSource(const std::string& module_name); |
| |
| // Return an object that contains the native methods defined by the named |
| // NativeHandler. |
| // |args[0]| - the name of a native handler object. |
| v8::Handle<v8::Value> RequireNativeFromString(const std::string& native_name); |
| void RequireNative(const v8::FunctionCallbackInfo<v8::Value>& args); |
| |
| // Wraps |source| in a (function(require, requireNative, exports) {...}). |
| v8::Handle<v8::String> WrapSource(v8::Handle<v8::String> source); |
| |
| // NativeHandler implementation which returns the private area of an Object. |
| void Private(const v8::FunctionCallbackInfo<v8::Value>& args); |
| |
| // NativeHandler implementation which returns a function wrapper for a |
| // provided function. |
| void CreateFunctionWrapper(const v8::FunctionCallbackInfo<v8::Value>& args); |
| |
| ScriptContext* context_; |
| |
| // A map from module names to the JS source for that module. GetSource() |
| // performs a lookup on this map. |
| SourceMap* source_map_; |
| |
| // A map from native handler names to native handlers. |
| NativeHandlerMap native_handler_map_; |
| |
| // When 0, natives are disabled, otherwise indicates how many callers have |
| // pinned natives as enabled. |
| int natives_enabled_; |
| |
| // Called when an exception is thrown but not caught in JS. Overridable by |
| // tests. |
| scoped_ptr<ExceptionHandler> exception_handler_; |
| |
| std::set<std::string> overridden_native_handlers_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ModuleSystem); |
| }; |
| |
| } // namespace extensions |
| |
| #endif // EXTENSIONS_RENDERER_MODULE_SYSTEM_H_ |