| // Copyright 2006 The Closure Library Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS-IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| /** |
| * @fileoverview JSON utility functions. |
| * @author arv@google.com (Erik Arvidsson) |
| */ |
| |
| |
| goog.provide('goog.json'); |
| goog.provide('goog.json.Replacer'); |
| goog.provide('goog.json.Reviver'); |
| goog.provide('goog.json.Serializer'); |
| |
| |
| /** |
| * @define {boolean} If true, use the native JSON parsing API. |
| * NOTE(ruilopes): EXPERIMENTAL, handle with care. Setting this to true might |
| * break your code. The default {@code goog.json.parse} implementation is able |
| * to handle invalid JSON, such as JSPB. |
| */ |
| goog.define('goog.json.USE_NATIVE_JSON', false); |
| |
| |
| /** |
| * Tests if a string is an invalid JSON string. This only ensures that we are |
| * not using any invalid characters |
| * @param {string} s The string to test. |
| * @return {boolean} True if the input is a valid JSON string. |
| */ |
| goog.json.isValid = function(s) { |
| // All empty whitespace is not valid. |
| if (/^\s*$/.test(s)) { |
| return false; |
| } |
| |
| // This is taken from http://www.json.org/json2.js which is released to the |
| // public domain. |
| // Changes: We dissallow \u2028 Line separator and \u2029 Paragraph separator |
| // inside strings. We also treat \u2028 and \u2029 as whitespace which they |
| // are in the RFC but IE and Safari does not match \s to these so we need to |
| // include them in the reg exps in all places where whitespace is allowed. |
| // We allowed \x7f inside strings because some tools don't escape it, |
| // e.g. http://www.json.org/java/org/json/JSONObject.java |
| |
| // Parsing happens in three stages. In the first stage, we run the text |
| // against regular expressions that look for non-JSON patterns. We are |
| // especially concerned with '()' and 'new' because they can cause invocation, |
| // and '=' because it can cause mutation. But just to be safe, we want to |
| // reject all unexpected forms. |
| |
| // We split the first stage into 4 regexp operations in order to work around |
| // crippling inefficiencies in IE's and Safari's regexp engines. First we |
| // replace all backslash pairs with '@' (a non-JSON character). Second, we |
| // replace all simple value tokens with ']' characters. Third, we delete all |
| // open brackets that follow a colon or comma or that begin the text. Finally, |
| // we look to see that the remaining characters are only whitespace or ']' or |
| // ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval. |
| |
| // Don't make these static since they have the global flag. |
| var backslashesRe = /\\["\\\/bfnrtu]/g; |
| var simpleValuesRe = |
| /"[^"\\\n\r\u2028\u2029\x00-\x08\x0a-\x1f]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g; |
| var openBracketsRe = /(?:^|:|,)(?:[\s\u2028\u2029]*\[)+/g; |
| var remainderRe = /^[\],:{}\s\u2028\u2029]*$/; |
| |
| return remainderRe.test(s.replace(backslashesRe, '@'). |
| replace(simpleValuesRe, ']'). |
| replace(openBracketsRe, '')); |
| }; |
| |
| |
| /** |
| * Parses a JSON string and returns the result. This throws an exception if |
| * the string is an invalid JSON string. |
| * |
| * Note that this is very slow on large strings. If you trust the source of |
| * the string then you should use unsafeParse instead. |
| * |
| * @param {*} s The JSON string to parse. |
| * @throws Error if s is invalid JSON. |
| * @return {Object} The object generated from the JSON string, or null. |
| */ |
| goog.json.parse = goog.json.USE_NATIVE_JSON ? |
| /** @type {function(*):Object} */ (goog.global['JSON']['parse']) : |
| function(s) { |
| var o = String(s); |
| if (goog.json.isValid(o)) { |
| /** @preserveTry */ |
| try { |
| return /** @type {Object} */ (eval('(' + o + ')')); |
| } catch (ex) { |
| } |
| } |
| throw Error('Invalid JSON string: ' + o); |
| }; |
| |
| |
| /** |
| * Parses a JSON string and returns the result. This uses eval so it is open |
| * to security issues and it should only be used if you trust the source. |
| * |
| * @param {string} s The JSON string to parse. |
| * @return {Object} The object generated from the JSON string. |
| */ |
| goog.json.unsafeParse = goog.json.USE_NATIVE_JSON ? |
| /** @type {function(string):Object} */ (goog.global['JSON']['parse']) : |
| function(s) { |
| return /** @type {Object} */ (eval('(' + s + ')')); |
| }; |
| |
| |
| /** |
| * JSON replacer, as defined in Section 15.12.3 of the ES5 spec. |
| * @see http://ecma-international.org/ecma-262/5.1/#sec-15.12.3 |
| * |
| * TODO(nicksantos): Array should also be a valid replacer. |
| * |
| * @typedef {function(this:Object, string, *): *} |
| */ |
| goog.json.Replacer; |
| |
| |
| /** |
| * JSON reviver, as defined in Section 15.12.2 of the ES5 spec. |
| * @see http://ecma-international.org/ecma-262/5.1/#sec-15.12.3 |
| * |
| * @typedef {function(this:Object, string, *): *} |
| */ |
| goog.json.Reviver; |
| |
| |
| /** |
| * Serializes an object or a value to a JSON string. |
| * |
| * @param {*} object The object to serialize. |
| * @param {?goog.json.Replacer=} opt_replacer A replacer function |
| * called for each (key, value) pair that determines how the value |
| * should be serialized. By defult, this just returns the value |
| * and allows default serialization to kick in. |
| * @throws Error if there are loops in the object graph. |
| * @return {string} A JSON string representation of the input. |
| */ |
| goog.json.serialize = goog.json.USE_NATIVE_JSON ? |
| /** @type {function(*, ?goog.json.Replacer=):string} */ |
| (goog.global['JSON']['stringify']) : |
| function(object, opt_replacer) { |
| // NOTE(nicksantos): Currently, we never use JSON.stringify. |
| // |
| // The last time I evaluated this, JSON.stringify had subtle bugs and |
| // behavior differences on all browsers, and the performance win was not |
| // large enough to justify all the issues. This may change in the future |
| // as browser implementations get better. |
| // |
| // assertSerialize in json_test contains if branches for the cases |
| // that fail. |
| return new goog.json.Serializer(opt_replacer).serialize(object); |
| }; |
| |
| |
| |
| /** |
| * Class that is used to serialize JSON objects to a string. |
| * @param {?goog.json.Replacer=} opt_replacer Replacer. |
| * @constructor |
| */ |
| goog.json.Serializer = function(opt_replacer) { |
| /** |
| * @type {goog.json.Replacer|null|undefined} |
| * @private |
| */ |
| this.replacer_ = opt_replacer; |
| }; |
| |
| |
| /** |
| * Serializes an object or a value to a JSON string. |
| * |
| * @param {*} object The object to serialize. |
| * @throws Error if there are loops in the object graph. |
| * @return {string} A JSON string representation of the input. |
| */ |
| goog.json.Serializer.prototype.serialize = function(object) { |
| var sb = []; |
| this.serializeInternal(object, sb); |
| return sb.join(''); |
| }; |
| |
| |
| /** |
| * Serializes a generic value to a JSON string |
| * @protected |
| * @param {*} object The object to serialize. |
| * @param {Array<string>} sb Array used as a string builder. |
| * @throws Error if there are loops in the object graph. |
| */ |
| goog.json.Serializer.prototype.serializeInternal = function(object, sb) { |
| switch (typeof object) { |
| case 'string': |
| this.serializeString_(/** @type {string} */ (object), sb); |
| break; |
| case 'number': |
| this.serializeNumber_(/** @type {number} */ (object), sb); |
| break; |
| case 'boolean': |
| sb.push(object); |
| break; |
| case 'undefined': |
| sb.push('null'); |
| break; |
| case 'object': |
| if (object == null) { |
| sb.push('null'); |
| break; |
| } |
| if (goog.isArray(object)) { |
| this.serializeArray(/** @type {!Array<?>} */ (object), sb); |
| break; |
| } |
| // should we allow new String, new Number and new Boolean to be treated |
| // as string, number and boolean? Most implementations do not and the |
| // need is not very big |
| this.serializeObject_(/** @type {Object} */ (object), sb); |
| break; |
| case 'function': |
| // Skip functions. |
| // TODO(user) Should we return something here? |
| break; |
| default: |
| throw Error('Unknown type: ' + typeof object); |
| } |
| }; |
| |
| |
| /** |
| * Character mappings used internally for goog.string.quote |
| * @private |
| * @type {!Object} |
| */ |
| goog.json.Serializer.charToJsonCharCache_ = { |
| '\"': '\\"', |
| '\\': '\\\\', |
| '/': '\\/', |
| '\b': '\\b', |
| '\f': '\\f', |
| '\n': '\\n', |
| '\r': '\\r', |
| '\t': '\\t', |
| |
| '\x0B': '\\u000b' // '\v' is not supported in JScript |
| }; |
| |
| |
| /** |
| * Regular expression used to match characters that need to be replaced. |
| * The S60 browser has a bug where unicode characters are not matched by |
| * regular expressions. The condition below detects such behaviour and |
| * adjusts the regular expression accordingly. |
| * @private |
| * @type {!RegExp} |
| */ |
| goog.json.Serializer.charsToReplace_ = /\uffff/.test('\uffff') ? |
| /[\\\"\x00-\x1f\x7f-\uffff]/g : /[\\\"\x00-\x1f\x7f-\xff]/g; |
| |
| |
| /** |
| * Serializes a string to a JSON string |
| * @private |
| * @param {string} s The string to serialize. |
| * @param {Array<string>} sb Array used as a string builder. |
| */ |
| goog.json.Serializer.prototype.serializeString_ = function(s, sb) { |
| // The official JSON implementation does not work with international |
| // characters. |
| sb.push('"', s.replace(goog.json.Serializer.charsToReplace_, function(c) { |
| // caching the result improves performance by a factor 2-3 |
| if (c in goog.json.Serializer.charToJsonCharCache_) { |
| return goog.json.Serializer.charToJsonCharCache_[c]; |
| } |
| |
| var cc = c.charCodeAt(0); |
| var rv = '\\u'; |
| if (cc < 16) { |
| rv += '000'; |
| } else if (cc < 256) { |
| rv += '00'; |
| } else if (cc < 4096) { // \u1000 |
| rv += '0'; |
| } |
| return goog.json.Serializer.charToJsonCharCache_[c] = rv + cc.toString(16); |
| }), '"'); |
| }; |
| |
| |
| /** |
| * Serializes a number to a JSON string |
| * @private |
| * @param {number} n The number to serialize. |
| * @param {Array<string>} sb Array used as a string builder. |
| */ |
| goog.json.Serializer.prototype.serializeNumber_ = function(n, sb) { |
| sb.push(isFinite(n) && !isNaN(n) ? n : 'null'); |
| }; |
| |
| |
| /** |
| * Serializes an array to a JSON string |
| * @param {Array<string>} arr The array to serialize. |
| * @param {Array<string>} sb Array used as a string builder. |
| * @protected |
| */ |
| goog.json.Serializer.prototype.serializeArray = function(arr, sb) { |
| var l = arr.length; |
| sb.push('['); |
| var sep = ''; |
| for (var i = 0; i < l; i++) { |
| sb.push(sep); |
| |
| var value = arr[i]; |
| this.serializeInternal( |
| this.replacer_ ? this.replacer_.call(arr, String(i), value) : value, |
| sb); |
| |
| sep = ','; |
| } |
| sb.push(']'); |
| }; |
| |
| |
| /** |
| * Serializes an object to a JSON string |
| * @private |
| * @param {Object} obj The object to serialize. |
| * @param {Array<string>} sb Array used as a string builder. |
| */ |
| goog.json.Serializer.prototype.serializeObject_ = function(obj, sb) { |
| sb.push('{'); |
| var sep = ''; |
| for (var key in obj) { |
| if (Object.prototype.hasOwnProperty.call(obj, key)) { |
| var value = obj[key]; |
| // Skip functions. |
| // TODO(ptucker) Should we return something for function properties? |
| if (typeof value != 'function') { |
| sb.push(sep); |
| this.serializeString_(key, sb); |
| sb.push(':'); |
| |
| this.serializeInternal( |
| this.replacer_ ? this.replacer_.call(obj, key, value) : value, |
| sb); |
| |
| sep = ','; |
| } |
| } |
| } |
| sb.push('}'); |
| }; |