// 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. #include "extensions/renderer/binding_generating_native_handler.h" #include "extensions/renderer/script_context.h" #include "extensions/renderer/v8_helpers.h" #include "gin/data_object_builder.h" #include "v8/include/v8-context.h" #include "v8/include/v8-function.h" #include "v8/include/v8-microtask-queue.h" namespace extensions { using v8_helpers::GetProperty; BindingGeneratingNativeHandler::BindingGeneratingNativeHandler( ScriptContext* context, const std::string& api_name, const std::string& bind_to) : context_(context), api_name_(api_name), bind_to_(bind_to) {} void BindingGeneratingNativeHandler::Initialize() {} bool BindingGeneratingNativeHandler::IsInitialized() { // There's no initialization to do, so just always return true. return true; } v8::Local BindingGeneratingNativeHandler::NewInstance() { // This long sequence of commands effectively runs the JavaScript code, // such that result[bind_to] is the compiled schema for |api_name|: // // var result = {}; // result[bind_to] = require('binding').Binding.create(api_name).generate(); // return result; // // Unfortunately using the v8 APIs makes that quite verbose. // Each stage is marked with the code it executes. v8::Isolate* isolate = context_->isolate(); v8::EscapableHandleScope scope(isolate); // Convert |api_name| and |bind_to| into their v8::Strings to pass // through the v8 APIs. v8::Local v8_api_name; if (!v8_helpers::ToV8String(isolate, api_name_, &v8_api_name)) { NOTREACHED(); return v8::Local(); } v8::Local v8_context = context_->v8_context(); // require('binding'); v8::Local binding_module; if (!context_->module_system()->Require("binding").ToLocal(&binding_module)) { NOTREACHED(); return v8::Local(); } // require('binding').Binding; v8::Local binding_value; v8::Local binding; if (!GetProperty(v8_context, binding_module, "Binding", &binding_value) || !binding_value->ToObject(v8_context).ToLocal(&binding)) { NOTREACHED(); return v8::Local(); } // require('binding').Binding.create; v8::Local create_binding_value; if (!GetProperty(v8_context, binding, "create", &create_binding_value) || !create_binding_value->IsFunction()) { NOTREACHED(); return v8::Local(); } v8::Local create_binding = create_binding_value.As(); // require('Binding').Binding.create(api_name); v8::Local binding_instance; { v8::Local argv[] = {v8_api_name}; v8::Local binding_instance_value; v8::MicrotasksScope microtasks_scope( v8_context->GetIsolate(), v8::MicrotasksScope::kDoNotRunMicrotasks); // TODO(devlin): We should not be using v8::Function::Call() directly here. // Instead, we should use JSRunner once it's used outside native bindings. if (!create_binding->Call(v8_context, binding, std::size(argv), argv) .ToLocal(&binding_instance_value) || !binding_instance_value->ToObject(v8_context) .ToLocal(&binding_instance)) { NOTREACHED(); return v8::Local(); } } // require('binding').Binding.create(api_name).generate; v8::Local generate_value; if (!GetProperty(v8_context, binding_instance, "generate", &generate_value) || !generate_value->IsFunction()) { NOTREACHED(); return v8::Local(); } v8::Local generate = generate_value.As(); // require('binding').Binding.create(api_name).generate(); v8::Local compiled_schema; { v8::MicrotasksScope microtasks_scope( v8_context->GetIsolate(), v8::MicrotasksScope::kDoNotRunMicrotasks); // TODO(devlin): We should not be using v8::Function::Call() directly here. // Instead, we should use JSRunner once it's used outside native bindings. if (!generate->Call(v8_context, binding_instance, 0, nullptr) .ToLocal(&compiled_schema)) { NOTREACHED(); return v8::Local(); } } // var result = {}; // result[bind_to] = ...; v8::Local object = gin::DataObjectBuilder(isolate).Set(bind_to_, compiled_schema).Build(); // return result; return scope.Escape(object); } } // namespace extensions