1 // Copyright 2013 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 #ifndef GIN_DICTIONARY_H_ 6 #define GIN_DICTIONARY_H_ 7 8 #include "gin/converter.h" 9 #include "gin/gin_export.h" 10 11 namespace gin { 12 13 // Dictionary is useful when writing bindings for a function that either 14 // receives an arbitrary JavaScript object as an argument or returns an 15 // arbitrary JavaScript object as a result. For example, Dictionary is useful 16 // when you might use the |dictionary| type in WebIDL: 17 // 18 // http://heycam.github.io/webidl/#idl-dictionaries 19 // 20 // WARNING: You cannot retain a Dictionary object in the heap. The underlying 21 // storage for Dictionary is tied to the closest enclosing 22 // v8::HandleScope. Generally speaking, you should store a Dictionary 23 // on the stack. 24 // 25 class GIN_EXPORT Dictionary { 26 public: 27 explicit Dictionary(v8::Isolate* isolate); 28 Dictionary(v8::Isolate* isolate, v8::Local<v8::Object> object); 29 Dictionary(const Dictionary& other); 30 ~Dictionary(); 31 32 static Dictionary CreateEmpty(v8::Isolate* isolate); 33 34 template<typename T> Get(const std::string & key,T * out)35 bool Get(const std::string& key, T* out) { 36 v8::Local<v8::Value> val; 37 if (!object_->Get(isolate_->GetCurrentContext(), StringToV8(isolate_, key)) 38 .ToLocal(&val)) { 39 return false; 40 } 41 return ConvertFromV8(isolate_, val, out); 42 } 43 44 template <typename T> Set(const std::string & key,const T & val)45 bool Set(const std::string& key, const T& val) { 46 v8::Local<v8::Value> v8_value; 47 if (!TryConvertToV8(isolate_, val, &v8_value)) 48 return false; 49 v8::Maybe<bool> result = 50 object_->Set(isolate_->GetCurrentContext(), StringToV8(isolate_, key), 51 v8_value); 52 return !result.IsNothing() && result.FromJust(); 53 } 54 isolate()55 v8::Isolate* isolate() const { return isolate_; } 56 57 private: 58 friend struct Converter<Dictionary>; 59 60 // TODO(aa): Remove this. Instead, get via FromV8(), Set(), and Get(). 61 v8::Isolate* isolate_; 62 v8::Local<v8::Object> object_; 63 }; 64 65 template<> 66 struct GIN_EXPORT Converter<Dictionary> { 67 static v8::Local<v8::Value> ToV8(v8::Isolate* isolate, 68 Dictionary val); 69 static bool FromV8(v8::Isolate* isolate, 70 v8::Local<v8::Value> val, 71 Dictionary* out); 72 }; 73 74 } // namespace gin 75 76 #endif // GIN_DICTIONARY_H_ 77