chrome/renderer/extensions/v8_schema_registry.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // TODO(dcarney): Remove this when UnsafePersistent is removed.
   6 #define V8_ALLOW_ACCESS_TO_RAW_HANDLE_CONSTRUCTOR
   7
   8 #include "chrome/renderer/extensions/v8_schema_registry.h"
   9
  10 #include "base/logging.h"
  11 #include "base/values.h"
  12 #include "chrome/renderer/extensions/chrome_v8_context.h"
  13 #include "chrome/renderer/extensions/object_backed_native_handler.h"
  14 #include "content/public/renderer/v8_value_converter.h"
  15 #include "extensions/common/extension_api.h"
  16
  17 using content::V8ValueConverter;
  18
  19 namespace extensions {
  20
  21 namespace {
  22
  23 class SchemaRegistryNativeHandler : public ObjectBackedNativeHandler {
  24  public:
  25   SchemaRegistryNativeHandler(V8SchemaRegistry* registry,
  26                               scoped_ptr<ChromeV8Context> context)
  27       : ObjectBackedNativeHandler(context.get()),
  28         context_(context.Pass()),
  29         registry_(registry) {
  30     RouteFunction("GetSchema",
  31         base::Bind(&SchemaRegistryNativeHandler::GetSchema,
  32                    base::Unretained(this)));
  33   }
  34
  35  private:
  36   void GetSchema(const v8::FunctionCallbackInfo<v8::Value>& args) {
  37     args.GetReturnValue().Set(
  38       registry_->GetSchema(*v8::String::Utf8Value(args[0])));
  39   }
  40
  41   scoped_ptr<ChromeV8Context> context_;
  42   V8SchemaRegistry* registry_;
  43 };
  44
  45 }  // namespace
  46
  47 V8SchemaRegistry::V8SchemaRegistry() {}
  48
  49 V8SchemaRegistry::~V8SchemaRegistry() {
  50   for (SchemaCache::iterator i = schema_cache_.begin();
  51        i != schema_cache_.end(); ++i) {
  52     i->second.dispose();
  53   }
  54 }
  55
  56 scoped_ptr<NativeHandler> V8SchemaRegistry::AsNativeHandler() {
  57   scoped_ptr<ChromeV8Context> context(new ChromeV8Context(
  58       GetOrCreateContext(v8::Isolate::GetCurrent()),
  59       NULL,  // no frame
  60       NULL,  // no extension
  61       Feature::UNSPECIFIED_CONTEXT));
  62   return scoped_ptr<NativeHandler>(
  63       new SchemaRegistryNativeHandler(this, context.Pass()));
  64 }
  65
  66 v8::Handle<v8::Array> V8SchemaRegistry::GetSchemas(
  67     const std::vector<std::string>& apis) {
  68   v8::Isolate* isolate = v8::Isolate::GetCurrent();
  69   v8::EscapableHandleScope handle_scope(isolate);
  70   v8::Context::Scope context_scope(GetOrCreateContext(isolate));
  71
  72   v8::Local<v8::Array> v8_apis(v8::Array::New(isolate, apis.size()));
  73   size_t api_index = 0;
  74   for (std::vector<std::string>::const_iterator i = apis.begin();
  75        i != apis.end(); ++i) {
  76     v8_apis->Set(api_index++, GetSchema(*i));
  77   }
  78   return handle_scope.Escape(v8_apis);
  79 }
  80
  81 v8::Handle<v8::Object> V8SchemaRegistry::GetSchema(const std::string& api) {
  82
  83   SchemaCache::iterator maybe_schema = schema_cache_.find(api);
  84   if (maybe_schema != schema_cache_.end())
  85     return maybe_schema->second.newLocal(v8::Isolate::GetCurrent());
  86
  87   v8::Isolate* isolate = v8::Isolate::GetCurrent();
  88   v8::EscapableHandleScope handle_scope(isolate);
  89   v8::Handle<v8::Context> context = GetOrCreateContext(isolate);
  90   v8::Context::Scope context_scope(context);
  91
  92   const base::DictionaryValue* schema =
  93       ExtensionAPI::GetSharedInstance()->GetSchema(api);
  94   CHECK(schema) << api;
  95   scoped_ptr<V8ValueConverter> v8_value_converter(V8ValueConverter::create());
  96   v8::Handle<v8::Value> value = v8_value_converter->ToV8Value(schema, context);
  97   CHECK(!value.IsEmpty());
  98
  99   v8::Persistent<v8::Object> v8_schema(context->GetIsolate(),
 100                                        v8::Handle<v8::Object>::Cast(value));
 101   v8::Local<v8::Object> to_return =
 102       v8::Local<v8::Object>::New(isolate, v8_schema);
 103   schema_cache_[api] = UnsafePersistent<v8::Object>(&v8_schema);
 104   return handle_scope.Escape(to_return);
 105 }
 106
 107 v8::Handle<v8::Context> V8SchemaRegistry::GetOrCreateContext(
 108     v8::Isolate* isolate) {
 109   // It's ok to create local handles in this function, since this is only called
 110   // when we have a HandleScope.
 111   if (context_.IsEmpty()) {
 112     v8::Handle<v8::Context> context = v8::Context::New(isolate);
 113     context_.reset(context);
 114     return context;
 115   }
 116   return context_.NewHandle(isolate);
 117 }
 118
 119 }  // namespace extensions