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 #ifndef CONTENT_PUBLIC_RENDERER_V8_VALUE_CONVERTER_H_ 6 #define CONTENT_PUBLIC_RENDERER_V8_VALUE_CONVERTER_H_ 7 8 #include "base/callback.h" 9 #include "content/common/content_export.h" 10 #include "v8/include/v8.h" 11 12 namespace base { 13 class Value; 14 } 15 16 namespace content { 17 18 // Converts between v8::Value (JavaScript values in the v8 heap) and Chrome's 19 // values (from base/values.h). Lists and dictionaries are converted 20 // recursively. 21 // 22 // The JSON types (null, boolean, string, number, array, and object) as well as 23 // binary values are supported. For binary values, we convert to WebKit 24 // ArrayBuffers, and support converting from an ArrayBuffer or any of the 25 // ArrayBufferView subclasses (Uint8Array, etc.). 26 class CONTENT_EXPORT V8ValueConverter { 27 public: 28 // Extends the default behaviour of V8ValueConverter. 29 class CONTENT_EXPORT Strategy { 30 public: 31 typedef base::Callback<base::Value*( 32 v8::Handle<v8::Value>, v8::Isolate* isolate)> FromV8ValueCallback; 33 34 virtual ~Strategy() {} 35 36 // If false is returned, V8ValueConverter proceeds with the default 37 // behavior. 38 // Use |callback| to convert any child values, as this will retain 39 // the ValueConverter's internal checks for depth and cycles. 40 virtual bool FromV8Object(v8::Handle<v8::Object> value, 41 base::Value** out, 42 v8::Isolate* isolate, 43 const FromV8ValueCallback& callback) const; 44 45 // If false is returned, V8ValueConverter proceeds with the default 46 // behavior. 47 // Use |callback| to convert any child values, as this will retain 48 // the ValueConverter's internal checks for depth and cycles. 49 virtual bool FromV8Array(v8::Handle<v8::Array> value, 50 base::Value** out, 51 v8::Isolate* isolate, 52 const FromV8ValueCallback& callback) const; 53 54 // If false is returned, V8ValueConverter proceeds with the default 55 // behavior. v8::Object is passed as ArrayBuffer and ArrayBufferView 56 // classes are siblings. 57 virtual bool FromV8ArrayBuffer(v8::Handle<v8::Object> value, 58 base::Value** out, 59 v8::Isolate* isolate) const; 60 61 // If false is returned, V8ValueConverter proceeds with the default 62 // behavior. This allows to intercept "non-finite" values and do something 63 // with them. 64 virtual bool FromV8Number(v8::Handle<v8::Number> value, 65 base::Value** out) const; 66 67 // If false is returned, V8ValueConverter proceeds with the default 68 // behavior. 69 virtual bool FromV8Undefined(base::Value** out) const; 70 }; 71 72 static V8ValueConverter* create(); 73 74 virtual ~V8ValueConverter() {} 75 76 // If true, Date objects are converted into DoubleValues with the number of 77 // seconds since Unix epoch. 78 // 79 // Otherwise they are converted into DictionaryValues with whatever additional 80 // properties has been set on them. 81 virtual void SetDateAllowed(bool val) = 0; 82 83 // If true, RegExp objects are converted into StringValues with the regular 84 // expression between / and /, for example "/ab?c/". 85 // 86 // Otherwise they are converted into DictionaryValues with whatever additional 87 // properties has been set on them. 88 virtual void SetRegExpAllowed(bool val) = 0; 89 90 // If true, Function objects are converted into DictionaryValues with whatever 91 // additional properties has been set on them. 92 // 93 // Otherwise they are treated as unsupported, see FromV8Value. 94 virtual void SetFunctionAllowed(bool val) = 0; 95 96 // If true, null values are stripped from objects. This is often useful when 97 // converting arguments to extension APIs. 98 virtual void SetStripNullFromObjects(bool val) = 0; 99 100 // Extend default behavior of V8ValueConverter. 101 virtual void SetStrategy(Strategy* strategy) = 0; 102 103 // Converts a base::Value to a v8::Value. 104 // 105 // Unsupported types are replaced with null. If an array or object throws 106 // while setting a value, that property or item is skipped, leaving a hole in 107 // the case of arrays. 108 virtual v8::Handle<v8::Value> ToV8Value( 109 const base::Value* value, 110 v8::Handle<v8::Context> context) const = 0; 111 112 // Converts a v8::Value to base::Value. 113 // 114 // Unsupported types (unless explicitly configured) are not converted, so 115 // this method may return NULL -- the exception is when converting arrays, 116 // where unsupported types are converted to Value(TYPE_NULL). 117 // 118 // Likewise, if an object throws while converting a property it will not be 119 // converted, whereas if an array throws while converting an item it will be 120 // converted to Value(TYPE_NULL). 121 virtual base::Value* FromV8Value(v8::Handle<v8::Value> value, 122 v8::Handle<v8::Context> context) const = 0; 123 }; 124 125 } // namespace content 126 127 #endif // CONTENT_PUBLIC_RENDERER_V8_VALUE_CONVERTER_H_ 128