[76] | 1 | /* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for |
---|
| 2 | * full list of contributors). Published under the Clear BSD license. |
---|
| 3 | * See http://svn.openlayers.org/trunk/openlayers/license.txt for the |
---|
| 4 | * full text of the license. */ |
---|
| 5 | |
---|
| 6 | /** |
---|
| 7 | * Note: |
---|
| 8 | * This work draws heavily from the public domain JSON serializer/deserializer |
---|
| 9 | * at http://www.json.org/json.js. Rewritten so that it doesn't modify |
---|
| 10 | * basic data prototypes. |
---|
| 11 | */ |
---|
| 12 | |
---|
| 13 | /** |
---|
| 14 | * @requires OpenLayers/Format.js |
---|
| 15 | */ |
---|
| 16 | |
---|
| 17 | /** |
---|
| 18 | * Class: OpenLayers.Format.JSON |
---|
| 19 | * A parser to read/write JSON safely. Create a new instance with the |
---|
| 20 | * <OpenLayers.Format.JSON> constructor. |
---|
| 21 | * |
---|
| 22 | * Inherits from: |
---|
| 23 | * - <OpenLayers.Format> |
---|
| 24 | */ |
---|
| 25 | OpenLayers.Format.JSON = OpenLayers.Class(OpenLayers.Format, { |
---|
| 26 | |
---|
| 27 | /** |
---|
| 28 | * APIProperty: indent |
---|
| 29 | * {String} For "pretty" printing, the indent string will be used once for |
---|
| 30 | * each indentation level. |
---|
| 31 | */ |
---|
| 32 | indent: " ", |
---|
| 33 | |
---|
| 34 | /** |
---|
| 35 | * APIProperty: space |
---|
| 36 | * {String} For "pretty" printing, the space string will be used after |
---|
| 37 | * the ":" separating a name/value pair. |
---|
| 38 | */ |
---|
| 39 | space: " ", |
---|
| 40 | |
---|
| 41 | /** |
---|
| 42 | * APIProperty: newline |
---|
| 43 | * {String} For "pretty" printing, the newline string will be used at the |
---|
| 44 | * end of each name/value pair or array item. |
---|
| 45 | */ |
---|
| 46 | newline: "\n", |
---|
| 47 | |
---|
| 48 | /** |
---|
| 49 | * Property: level |
---|
| 50 | * {Integer} For "pretty" printing, this is incremented/decremented during |
---|
| 51 | * serialization. |
---|
| 52 | */ |
---|
| 53 | level: 0, |
---|
| 54 | |
---|
| 55 | /** |
---|
| 56 | * Property: pretty |
---|
| 57 | * {Boolean} Serialize with extra whitespace for structure. This is set |
---|
| 58 | * by the <write> method. |
---|
| 59 | */ |
---|
| 60 | pretty: false, |
---|
| 61 | |
---|
| 62 | /** |
---|
| 63 | * Constructor: OpenLayers.Format.JSON |
---|
| 64 | * Create a new parser for JSON. |
---|
| 65 | * |
---|
| 66 | * Parameters: |
---|
| 67 | * options - {Object} An optional object whose properties will be set on |
---|
| 68 | * this instance. |
---|
| 69 | */ |
---|
| 70 | initialize: function(options) { |
---|
| 71 | OpenLayers.Format.prototype.initialize.apply(this, [options]); |
---|
| 72 | }, |
---|
| 73 | |
---|
| 74 | /** |
---|
| 75 | * APIMethod: read |
---|
| 76 | * Deserialize a json string. |
---|
| 77 | * |
---|
| 78 | * Parameters: |
---|
| 79 | * json - {String} A JSON string |
---|
| 80 | * filter - {Function} A function which will be called for every key and |
---|
| 81 | * value at every level of the final result. Each value will be |
---|
| 82 | * replaced by the result of the filter function. This can be used to |
---|
| 83 | * reform generic objects into instances of classes, or to transform |
---|
| 84 | * date strings into Date objects. |
---|
| 85 | * |
---|
| 86 | * Returns: |
---|
| 87 | * {Object} An object, array, string, or number . |
---|
| 88 | */ |
---|
| 89 | read: function(json, filter) { |
---|
| 90 | /** |
---|
| 91 | * Parsing happens in three stages. In the first stage, we run the text |
---|
| 92 | * against a regular expression which looks for non-JSON |
---|
| 93 | * characters. We are especially concerned with '()' and 'new' |
---|
| 94 | * because they can cause invocation, and '=' because it can cause |
---|
| 95 | * mutation. But just to be safe, we will reject all unexpected |
---|
| 96 | * characters. |
---|
| 97 | */ |
---|
| 98 | try { |
---|
| 99 | if (/^[\],:{}\s]*$/.test(json.replace(/\\["\\\/bfnrtu]/g, '@'). |
---|
| 100 | replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']'). |
---|
| 101 | replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) { |
---|
| 102 | |
---|
| 103 | /** |
---|
| 104 | * In the second stage we use the eval function to compile the |
---|
| 105 | * text into a JavaScript structure. The '{' operator is |
---|
| 106 | * subject to a syntactic ambiguity in JavaScript - it can |
---|
| 107 | * begin a block or an object literal. We wrap the text in |
---|
| 108 | * parens to eliminate the ambiguity. |
---|
| 109 | */ |
---|
| 110 | var object = eval('(' + json + ')'); |
---|
| 111 | |
---|
| 112 | /** |
---|
| 113 | * In the optional third stage, we recursively walk the new |
---|
| 114 | * structure, passing each name/value pair to a filter |
---|
| 115 | * function for possible transformation. |
---|
| 116 | */ |
---|
| 117 | if(typeof filter === 'function') { |
---|
| 118 | function walk(k, v) { |
---|
| 119 | if(v && typeof v === 'object') { |
---|
| 120 | for(var i in v) { |
---|
| 121 | if(v.hasOwnProperty(i)) { |
---|
| 122 | v[i] = walk(i, v[i]); |
---|
| 123 | } |
---|
| 124 | } |
---|
| 125 | } |
---|
| 126 | return filter(k, v); |
---|
| 127 | } |
---|
| 128 | object = walk('', object); |
---|
| 129 | } |
---|
| 130 | |
---|
| 131 | if(this.keepData) { |
---|
| 132 | this.data = object; |
---|
| 133 | } |
---|
| 134 | |
---|
| 135 | return object; |
---|
| 136 | } |
---|
| 137 | } catch(e) { |
---|
| 138 | // Fall through if the regexp test fails. |
---|
| 139 | } |
---|
| 140 | return null; |
---|
| 141 | }, |
---|
| 142 | |
---|
| 143 | /** |
---|
| 144 | * APIMethod: write |
---|
| 145 | * Serialize an object into a JSON string. |
---|
| 146 | * |
---|
| 147 | * Parameters: |
---|
| 148 | * value - {String} The object, array, string, number, boolean or date |
---|
| 149 | * to be serialized. |
---|
| 150 | * pretty - {Boolean} Structure the output with newlines and indentation. |
---|
| 151 | * Default is false. |
---|
| 152 | * |
---|
| 153 | * Returns: |
---|
| 154 | * {String} The JSON string representation of the input value. |
---|
| 155 | */ |
---|
| 156 | write: function(value, pretty) { |
---|
| 157 | this.pretty = !!pretty; |
---|
| 158 | var json = null; |
---|
| 159 | var type = typeof value; |
---|
| 160 | if(this.serialize[type]) { |
---|
| 161 | try { |
---|
| 162 | json = this.serialize[type].apply(this, [value]); |
---|
| 163 | } catch(err) { |
---|
| 164 | OpenLayers.Console.error("Trouble serializing: " + err); |
---|
| 165 | } |
---|
| 166 | } |
---|
| 167 | return json; |
---|
| 168 | }, |
---|
| 169 | |
---|
| 170 | /** |
---|
| 171 | * Method: writeIndent |
---|
| 172 | * Output an indentation string depending on the indentation level. |
---|
| 173 | * |
---|
| 174 | * Returns: |
---|
| 175 | * {String} An appropriate indentation string. |
---|
| 176 | */ |
---|
| 177 | writeIndent: function() { |
---|
| 178 | var pieces = []; |
---|
| 179 | if(this.pretty) { |
---|
| 180 | for(var i=0; i<this.level; ++i) { |
---|
| 181 | pieces.push(this.indent); |
---|
| 182 | } |
---|
| 183 | } |
---|
| 184 | return pieces.join(''); |
---|
| 185 | }, |
---|
| 186 | |
---|
| 187 | /** |
---|
| 188 | * Method: writeNewline |
---|
| 189 | * Output a string representing a newline if in pretty printing mode. |
---|
| 190 | * |
---|
| 191 | * Returns: |
---|
| 192 | * {String} A string representing a new line. |
---|
| 193 | */ |
---|
| 194 | writeNewline: function() { |
---|
| 195 | return (this.pretty) ? this.newline : ''; |
---|
| 196 | }, |
---|
| 197 | |
---|
| 198 | /** |
---|
| 199 | * Method: writeSpace |
---|
| 200 | * Output a string representing a space if in pretty printing mode. |
---|
| 201 | * |
---|
| 202 | * Returns: |
---|
| 203 | * {String} A space. |
---|
| 204 | */ |
---|
| 205 | writeSpace: function() { |
---|
| 206 | return (this.pretty) ? this.space : ''; |
---|
| 207 | }, |
---|
| 208 | |
---|
| 209 | /** |
---|
| 210 | * Property: serialize |
---|
| 211 | * Object with properties corresponding to the serializable data types. |
---|
| 212 | * Property values are functions that do the actual serializing. |
---|
| 213 | */ |
---|
| 214 | serialize: { |
---|
| 215 | /** |
---|
| 216 | * Method: serialize.object |
---|
| 217 | * Transform an object into a JSON string. |
---|
| 218 | * |
---|
| 219 | * Parameters: |
---|
| 220 | * object - {Object} The object to be serialized. |
---|
| 221 | * |
---|
| 222 | * Returns: |
---|
| 223 | * {String} A JSON string representing the object. |
---|
| 224 | */ |
---|
| 225 | 'object': function(object) { |
---|
| 226 | // three special objects that we want to treat differently |
---|
| 227 | if(object == null) { |
---|
| 228 | return "null"; |
---|
| 229 | } |
---|
| 230 | if(object.constructor == Date) { |
---|
| 231 | return this.serialize.date.apply(this, [object]); |
---|
| 232 | } |
---|
| 233 | if(object.constructor == Array) { |
---|
| 234 | return this.serialize.array.apply(this, [object]); |
---|
| 235 | } |
---|
| 236 | var pieces = ['{']; |
---|
| 237 | this.level += 1; |
---|
| 238 | var key, keyJSON, valueJSON; |
---|
| 239 | |
---|
| 240 | var addComma = false; |
---|
| 241 | for(key in object) { |
---|
| 242 | if(object.hasOwnProperty(key)) { |
---|
| 243 | // recursive calls need to allow for sub-classing |
---|
| 244 | keyJSON = OpenLayers.Format.JSON.prototype.write.apply(this, |
---|
| 245 | [key, this.pretty]); |
---|
| 246 | valueJSON = OpenLayers.Format.JSON.prototype.write.apply(this, |
---|
| 247 | [object[key], this.pretty]); |
---|
| 248 | if(keyJSON != null && valueJSON != null) { |
---|
| 249 | if(addComma) { |
---|
| 250 | pieces.push(','); |
---|
| 251 | } |
---|
| 252 | pieces.push(this.writeNewline(), this.writeIndent(), |
---|
| 253 | keyJSON, ':', this.writeSpace(), valueJSON); |
---|
| 254 | addComma = true; |
---|
| 255 | } |
---|
| 256 | } |
---|
| 257 | } |
---|
| 258 | |
---|
| 259 | this.level -= 1; |
---|
| 260 | pieces.push(this.writeNewline(), this.writeIndent(), '}'); |
---|
| 261 | return pieces.join(''); |
---|
| 262 | }, |
---|
| 263 | |
---|
| 264 | /** |
---|
| 265 | * Method: serialize.array |
---|
| 266 | * Transform an array into a JSON string. |
---|
| 267 | * |
---|
| 268 | * Parameters: |
---|
| 269 | * array - {Array} The array to be serialized |
---|
| 270 | * |
---|
| 271 | * Returns: |
---|
| 272 | * {String} A JSON string representing the array. |
---|
| 273 | */ |
---|
| 274 | 'array': function(array) { |
---|
| 275 | var json; |
---|
| 276 | var pieces = ['[']; |
---|
| 277 | this.level += 1; |
---|
| 278 | |
---|
| 279 | for(var i=0, len=array.length; i<len; ++i) { |
---|
| 280 | // recursive calls need to allow for sub-classing |
---|
| 281 | json = OpenLayers.Format.JSON.prototype.write.apply(this, |
---|
| 282 | [array[i], this.pretty]); |
---|
| 283 | if(json != null) { |
---|
| 284 | if(i > 0) { |
---|
| 285 | pieces.push(','); |
---|
| 286 | } |
---|
| 287 | pieces.push(this.writeNewline(), this.writeIndent(), json); |
---|
| 288 | } |
---|
| 289 | } |
---|
| 290 | |
---|
| 291 | this.level -= 1; |
---|
| 292 | pieces.push(this.writeNewline(), this.writeIndent(), ']'); |
---|
| 293 | return pieces.join(''); |
---|
| 294 | }, |
---|
| 295 | |
---|
| 296 | /** |
---|
| 297 | * Method: serialize.string |
---|
| 298 | * Transform a string into a JSON string. |
---|
| 299 | * |
---|
| 300 | * Parameters: |
---|
| 301 | * string - {String} The string to be serialized |
---|
| 302 | * |
---|
| 303 | * Returns: |
---|
| 304 | * {String} A JSON string representing the string. |
---|
| 305 | */ |
---|
| 306 | 'string': function(string) { |
---|
| 307 | // If the string contains no control characters, no quote characters, and no |
---|
| 308 | // backslash characters, then we can simply slap some quotes around it. |
---|
| 309 | // Otherwise we must also replace the offending characters with safe |
---|
| 310 | // sequences. |
---|
| 311 | var m = { |
---|
| 312 | '\b': '\\b', |
---|
| 313 | '\t': '\\t', |
---|
| 314 | '\n': '\\n', |
---|
| 315 | '\f': '\\f', |
---|
| 316 | '\r': '\\r', |
---|
| 317 | '"' : '\\"', |
---|
| 318 | '\\': '\\\\' |
---|
| 319 | }; |
---|
| 320 | if(/["\\\x00-\x1f]/.test(string)) { |
---|
| 321 | return '"' + string.replace(/([\x00-\x1f\\"])/g, function(a, b) { |
---|
| 322 | var c = m[b]; |
---|
| 323 | if(c) { |
---|
| 324 | return c; |
---|
| 325 | } |
---|
| 326 | c = b.charCodeAt(); |
---|
| 327 | return '\\u00' + |
---|
| 328 | Math.floor(c / 16).toString(16) + |
---|
| 329 | (c % 16).toString(16); |
---|
| 330 | }) + '"'; |
---|
| 331 | } |
---|
| 332 | return '"' + string + '"'; |
---|
| 333 | }, |
---|
| 334 | |
---|
| 335 | /** |
---|
| 336 | * Method: serialize.number |
---|
| 337 | * Transform a number into a JSON string. |
---|
| 338 | * |
---|
| 339 | * Parameters: |
---|
| 340 | * number - {Number} The number to be serialized. |
---|
| 341 | * |
---|
| 342 | * Returns: |
---|
| 343 | * {String} A JSON string representing the number. |
---|
| 344 | */ |
---|
| 345 | 'number': function(number) { |
---|
| 346 | return isFinite(number) ? String(number) : "null"; |
---|
| 347 | }, |
---|
| 348 | |
---|
| 349 | /** |
---|
| 350 | * Method: serialize.boolean |
---|
| 351 | * Transform a boolean into a JSON string. |
---|
| 352 | * |
---|
| 353 | * Parameters: |
---|
| 354 | * bool - {Boolean} The boolean to be serialized. |
---|
| 355 | * |
---|
| 356 | * Returns: |
---|
| 357 | * {String} A JSON string representing the boolean. |
---|
| 358 | */ |
---|
| 359 | 'boolean': function(bool) { |
---|
| 360 | return String(bool); |
---|
| 361 | }, |
---|
| 362 | |
---|
| 363 | /** |
---|
| 364 | * Method: serialize.object |
---|
| 365 | * Transform a date into a JSON string. |
---|
| 366 | * |
---|
| 367 | * Parameters: |
---|
| 368 | * date - {Date} The date to be serialized. |
---|
| 369 | * |
---|
| 370 | * Returns: |
---|
| 371 | * {String} A JSON string representing the date. |
---|
| 372 | */ |
---|
| 373 | 'date': function(date) { |
---|
| 374 | function format(number) { |
---|
| 375 | // Format integers to have at least two digits. |
---|
| 376 | return (number < 10) ? '0' + number : number; |
---|
| 377 | } |
---|
| 378 | return '"' + date.getFullYear() + '-' + |
---|
| 379 | format(date.getMonth() + 1) + '-' + |
---|
| 380 | format(date.getDate()) + 'T' + |
---|
| 381 | format(date.getHours()) + ':' + |
---|
| 382 | format(date.getMinutes()) + ':' + |
---|
| 383 | format(date.getSeconds()) + '"'; |
---|
| 384 | } |
---|
| 385 | }, |
---|
| 386 | |
---|
| 387 | CLASS_NAME: "OpenLayers.Format.JSON" |
---|
| 388 | |
---|
| 389 | }); |
---|