Cake/Cache/Cache.php
| 1 | <?php |
|---|---|
| 2 | /** |
| 3 | * CakePHP(tm) : Rapid Development Framework (http://cakephp.org) |
| 4 | * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org) |
| 5 | * |
| 6 | * Licensed under The MIT License |
| 7 | * Redistributions of files must retain the above copyright notice. |
| 8 | * |
| 9 | * @copyright Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org) |
| 10 | * @link http://cakephp.org CakePHP(tm) Project |
| 11 | * @package Cake.Cache |
| 12 | * @since CakePHP(tm) v 1.2.0.4933 |
| 13 | * @license MIT License (http://www.opensource.org/licenses/mit-license.php) |
| 14 | */ |
| 15 | |
| 16 | App::uses('Inflector', 'Utility'); |
| 17 | App::uses('CacheEngine', 'Cache'); |
| 18 | |
| 19 | /** |
| 20 | * Cache provides a consistent interface to Caching in your application. It allows you |
| 21 | * to use several different Cache engines, without coupling your application to a specific |
| 22 | * implementation. It also allows you to change out cache storage or configuration without effecting |
| 23 | * the rest of your application. |
| 24 | * |
| 25 | * You can configure Cache engines in your application's `bootstrap.php` file. A sample configuration would |
| 26 | * be |
| 27 | * |
| 28 | * {{{ |
| 29 | * Cache::config('shared', array( |
| 30 | * 'engine' => 'Apc', |
| 31 | * 'prefix' => 'my_app_' |
| 32 | * )); |
| 33 | * }}} |
| 34 | * |
| 35 | * This would configure an APC cache engine to the 'shared' alias. You could then read and write |
| 36 | * to that cache alias by using it for the `$config` parameter in the various Cache methods. In |
| 37 | * general all Cache operations are supported by all cache engines. However, Cache::increment() and |
| 38 | * Cache::decrement() are not supported by File caching. |
| 39 | * |
| 40 | * @package Cake.Cache |
| 41 | */ |
| 42 | class Cache { |
| 43 | |
| 44 | /** |
| 45 | * Cache configuration stack |
| 46 | * Keeps the permanent/default settings for each cache engine. |
| 47 | * These settings are used to reset the engines after temporary modification. |
| 48 | * |
| 49 | * @var array |
| 50 | */ |
| 51 | protected static $_config = array(); |
| 52 | |
| 53 | /** |
| 54 | * Whether to reset the settings with the next call to Cache::set(); |
| 55 | * |
| 56 | * @var array |
| 57 | */ |
| 58 | protected static $_reset = false; |
| 59 | |
| 60 | /** |
| 61 | * Engine instances keyed by configuration name. |
| 62 | * |
| 63 | * @var array |
| 64 | */ |
| 65 | protected static $_engines = array(); |
| 66 | |
| 67 | /** |
| 68 | * Set the cache configuration to use. config() can |
| 69 | * both create new configurations, return the settings for already configured |
| 70 | * configurations. |
| 71 | * |
| 72 | * To create a new configuration, or to modify an existing configuration permanently: |
| 73 | * |
| 74 | * `Cache::config('my_config', array('engine' => 'File', 'path' => TMP));` |
| 75 | * |
| 76 | * If you need to modify a configuration temporarily, use Cache::set(). |
| 77 | * To get the settings for a configuration: |
| 78 | * |
| 79 | * `Cache::config('default');` |
| 80 | * |
| 81 | * There are 5 built-in caching engines: |
| 82 | * |
| 83 | * - `FileEngine` - Uses simple files to store content. Poor performance, but good for |
| 84 | * storing large objects, or things that are not IO sensitive. |
| 85 | * - `ApcEngine` - Uses the APC object cache, one of the fastest caching engines. |
| 86 | * - `MemcacheEngine` - Uses the PECL::Memcache extension and Memcached for storage. |
| 87 | * Fast reads/writes, and benefits from memcache being distributed. |
| 88 | * - `XcacheEngine` - Uses the Xcache extension, an alternative to APC. |
| 89 | * - `WincacheEngine` - Uses Windows Cache Extension for PHP. Supports wincache 1.1.0 and higher. |
| 90 | * |
| 91 | * The following keys are used in core cache engines: |
| 92 | * |
| 93 | * - `duration` Specify how long items in this cache configuration last. |
| 94 | * - `prefix` Prefix appended to all entries. Good for when you need to share a keyspace |
| 95 | * with either another cache config or another application. |
| 96 | * - `probability` Probability of hitting a cache gc cleanup. Setting to 0 will disable |
| 97 | * cache::gc from ever being called automatically. |
| 98 | * - `servers' Used by memcache. Give the address of the memcached servers to use. |
| 99 | * - `compress` Used by memcache. Enables memcache's compressed format. |
| 100 | * - `serialize` Used by FileCache. Should cache objects be serialized first. |
| 101 | * - `path` Used by FileCache. Path to where cachefiles should be saved. |
| 102 | * - `lock` Used by FileCache. Should files be locked before writing to them? |
| 103 | * - `user` Used by Xcache. Username for XCache |
| 104 | * - `password` Used by Xcache. Password for XCache |
| 105 | * |
| 106 | * @see app/Config/core.php for configuration settings |
| 107 | * @param string $name Name of the configuration |
| 108 | * @param array $settings Optional associative array of settings passed to the engine |
| 109 | * @return array(engine, settings) on success, false on failure |
| 110 | * @throws CacheException |
| 111 | */ |
| 112 | public static function config($name = null, $settings = array()) { |
| 113 | if (is_array($name)) { |
| 114 | $settings = $name; |
| 115 | } |
| 116 | |
| 117 | $current = array(); |
| 118 | if (isset(self::$_config[$name])) { |
| 119 | $current = self::$_config[$name]; |
| 120 | } |
| 121 | |
| 122 | if (!empty($settings)) { |
| 123 | self::$_config[$name] = array_merge($current, $settings); |
| 124 | } |
| 125 | |
| 126 | if (empty(self::$_config[$name]['engine'])) { |
| 127 | return false; |
| 128 | } |
| 129 | |
| 130 | $engine = self::$_config[$name]['engine']; |
| 131 | |
| 132 | if (!isset(self::$_engines[$name])) { |
| 133 | self::_buildEngine($name); |
| 134 | $settings = self::$_config[$name] = self::settings($name); |
| 135 | } elseif ($settings = self::set(self::$_config[$name], null, $name)) { |
| 136 | self::$_config[$name] = $settings; |
| 137 | } |
| 138 | return compact('engine', 'settings'); |
| 139 | } |
| 140 | |
| 141 | /** |
| 142 | * Finds and builds the instance of the required engine class. |
| 143 | * |
| 144 | * @param string $name Name of the config array that needs an engine instance built |
| 145 | * @return boolean |
| 146 | * @throws CacheException |
| 147 | */ |
| 148 | protected static function _buildEngine($name) { |
| 149 | $config = self::$_config[$name]; |
| 150 | |
| 151 | list($plugin, $class) = pluginSplit($config['engine'], true); |
| 152 | $cacheClass = $class . 'Engine'; |
| 153 | App::uses($cacheClass, $plugin . 'Cache/Engine'); |
| 154 | if (!class_exists($cacheClass)) { |
| 155 | return false; |
| 156 | } |
| 157 | $cacheClass = $class . 'Engine'; |
| 158 | if (!is_subclass_of($cacheClass, 'CacheEngine')) { |
| 159 | throw new CacheException(__d('cake_dev', 'Cache engines must use CacheEngine as a base class.')); |
| 160 | } |
| 161 | self::$_engines[$name] = new $cacheClass(); |
| 162 | if (self::$_engines[$name]->init($config)) { |
| 163 | if (self::$_engines[$name]->settings['probability'] && time() % self::$_engines[$name]->settings['probability'] === 0) { |
| 164 | self::$_engines[$name]->gc(); |
| 165 | } |
| 166 | return true; |
| 167 | } |
| 168 | return false; |
| 169 | } |
| 170 | |
| 171 | /** |
| 172 | * Returns an array containing the currently configured Cache settings. |
| 173 | * |
| 174 | * @return array Array of configured Cache config names. |
| 175 | */ |
| 176 | public static function configured() { |
| 177 | return array_keys(self::$_config); |
| 178 | } |
| 179 | |
| 180 | /** |
| 181 | * Drops a cache engine. Deletes the cache configuration information |
| 182 | * If the deleted configuration is the last configuration using an certain engine, |
| 183 | * the Engine instance is also unset. |
| 184 | * |
| 185 | * @param string $name A currently configured cache config you wish to remove. |
| 186 | * @return boolean success of the removal, returns false when the config does not exist. |
| 187 | */ |
| 188 | public static function drop($name) { |
| 189 | if (!isset(self::$_config[$name])) { |
| 190 | return false; |
| 191 | } |
| 192 | unset(self::$_config[$name], self::$_engines[$name]); |
| 193 | return true; |
| 194 | } |
| 195 | |
| 196 | /** |
| 197 | * Temporarily change the settings on a cache config. The settings will persist for the next write |
| 198 | * operation (write, decrement, increment, clear). Any reads that are done before the write, will |
| 199 | * use the modified settings. If `$settings` is empty, the settings will be reset to the |
| 200 | * original configuration. |
| 201 | * |
| 202 | * Can be called with 2 or 3 parameters. To set multiple values at once. |
| 203 | * |
| 204 | * `Cache::set(array('duration' => '+30 minutes'), 'my_config');` |
| 205 | * |
| 206 | * Or to set one value. |
| 207 | * |
| 208 | * `Cache::set('duration', '+30 minutes', 'my_config');` |
| 209 | * |
| 210 | * To reset a config back to the originally configured values. |
| 211 | * |
| 212 | * `Cache::set(null, 'my_config');` |
| 213 | * |
| 214 | * @param mixed $settings Optional string for simple name-value pair or array |
| 215 | * @param string $value Optional for a simple name-value pair |
| 216 | * @param string $config The configuration name you are changing. Defaults to 'default' |
| 217 | * @return array Array of settings. |
| 218 | */ |
| 219 | public static function set($settings = array(), $value = null, $config = 'default') { |
| 220 | if (is_array($settings) && $value !== null) { |
| 221 | $config = $value; |
| 222 | } |
| 223 | if (!isset(self::$_config[$config]) || !isset(self::$_engines[$config])) { |
| 224 | return false; |
| 225 | } |
| 226 | if (!empty($settings)) { |
| 227 | self::$_reset = true; |
| 228 | } |
| 229 | |
| 230 | if (self::$_reset === true) { |
| 231 | if (empty($settings)) { |
| 232 | self::$_reset = false; |
| 233 | $settings = self::$_config[$config]; |
| 234 | } else { |
| 235 | if (is_string($settings) && $value !== null) { |
| 236 | $settings = array($settings => $value); |
| 237 | } |
| 238 | $settings = array_merge(self::$_config[$config], $settings); |
| 239 | if (isset($settings['duration']) && !is_numeric($settings['duration'])) { |
| 240 | $settings['duration'] = strtotime($settings['duration']) - time(); |
| 241 | } |
| 242 | } |
| 243 | self::$_engines[$config]->settings = $settings; |
| 244 | } |
| 245 | return self::settings($config); |
| 246 | } |
| 247 | |
| 248 | /** |
| 249 | * Garbage collection |
| 250 | * |
| 251 | * Permanently remove all expired and deleted data |
| 252 | * |
| 253 | * @param string $config The config name you wish to have garbage collected. Defaults to 'default' |
| 254 | * @return void |
| 255 | */ |
| 256 | public static function gc($config = 'default') { |
| 257 | self::$_engines[$config]->gc(); |
| 258 | } |
| 259 | |
| 260 | /** |
| 261 | * Write data for key into cache. Will automatically use the currently |
| 262 | * active cache configuration. To set the currently active configuration use |
| 263 | * Cache::config() |
| 264 | * |
| 265 | * ### Usage: |
| 266 | * |
| 267 | * Writing to the active cache config: |
| 268 | * |
| 269 | * `Cache::write('cached_data', $data);` |
| 270 | * |
| 271 | * Writing to a specific cache config: |
| 272 | * |
| 273 | * `Cache::write('cached_data', $data, 'long_term');` |
| 274 | * |
| 275 | * @param string $key Identifier for the data |
| 276 | * @param mixed $value Data to be cached - anything except a resource |
| 277 | * @param string $config Optional string configuration name to write to. Defaults to 'default' |
| 278 | * @return boolean True if the data was successfully cached, false on failure |
| 279 | */ |
| 280 | public static function write($key, $value, $config = 'default') { |
| 281 | $settings = self::settings($config); |
| 282 | |
| 283 | if (empty($settings)) { |
| 284 | return false; |
| 285 | } |
| 286 | if (!self::isInitialized($config)) { |
| 287 | return false; |
| 288 | } |
| 289 | $key = self::$_engines[$config]->key($key); |
| 290 | |
| 291 | if (!$key || is_resource($value)) { |
| 292 | return false; |
| 293 | } |
| 294 | |
| 295 | $success = self::$_engines[$config]->write($settings['prefix'] . $key, $value, $settings['duration']); |
| 296 | self::set(null, $config); |
| 297 | if ($success === false && $value !== '') { |
| 298 | trigger_error( |
| 299 | __d('cake_dev', |
| 300 | "%s cache was unable to write '%s' to %s cache", |
| 301 | $config, |
| 302 | $key, |
| 303 | self::$_engines[$config]->settings['engine'] |
| 304 | ), |
| 305 | E_USER_WARNING |
| 306 | ); |
| 307 | } |
| 308 | return $success; |
| 309 | } |
| 310 | |
| 311 | /** |
| 312 | * Read a key from the cache. Will automatically use the currently |
| 313 | * active cache configuration. To set the currently active configuration use |
| 314 | * Cache::config() |
| 315 | * |
| 316 | * ### Usage: |
| 317 | * |
| 318 | * Reading from the active cache configuration. |
| 319 | * |
| 320 | * `Cache::read('my_data');` |
| 321 | * |
| 322 | * Reading from a specific cache configuration. |
| 323 | * |
| 324 | * `Cache::read('my_data', 'long_term');` |
| 325 | * |
| 326 | * @param string $key Identifier for the data |
| 327 | * @param string $config optional name of the configuration to use. Defaults to 'default' |
| 328 | * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it |
| 329 | */ |
| 330 | public static function read($key, $config = 'default') { |
| 331 | $settings = self::settings($config); |
| 332 | |
| 333 | if (empty($settings)) { |
| 334 | return false; |
| 335 | } |
| 336 | if (!self::isInitialized($config)) { |
| 337 | return false; |
| 338 | } |
| 339 | $key = self::$_engines[$config]->key($key); |
| 340 | if (!$key) { |
| 341 | return false; |
| 342 | } |
| 343 | return self::$_engines[$config]->read($settings['prefix'] . $key); |
| 344 | } |
| 345 | |
| 346 | /** |
| 347 | * Increment a number under the key and return incremented value. |
| 348 | * |
| 349 | * @param string $key Identifier for the data |
| 350 | * @param integer $offset How much to add |
| 351 | * @param string $config Optional string configuration name. Defaults to 'default' |
| 352 | * @return mixed new value, or false if the data doesn't exist, is not integer, |
| 353 | * or if there was an error fetching it. |
| 354 | */ |
| 355 | public static function increment($key, $offset = 1, $config = 'default') { |
| 356 | $settings = self::settings($config); |
| 357 | |
| 358 | if (empty($settings)) { |
| 359 | return false; |
| 360 | } |
| 361 | if (!self::isInitialized($config)) { |
| 362 | return false; |
| 363 | } |
| 364 | $key = self::$_engines[$config]->key($key); |
| 365 | |
| 366 | if (!$key || !is_integer($offset) || $offset < 0) { |
| 367 | return false; |
| 368 | } |
| 369 | $success = self::$_engines[$config]->increment($settings['prefix'] . $key, $offset); |
| 370 | self::set(null, $config); |
| 371 | return $success; |
| 372 | } |
| 373 | |
| 374 | /** |
| 375 | * Decrement a number under the key and return decremented value. |
| 376 | * |
| 377 | * @param string $key Identifier for the data |
| 378 | * @param integer $offset How much to subtract |
| 379 | * @param string $config Optional string configuration name. Defaults to 'default' |
| 380 | * @return mixed new value, or false if the data doesn't exist, is not integer, |
| 381 | * or if there was an error fetching it |
| 382 | */ |
| 383 | public static function decrement($key, $offset = 1, $config = 'default') { |
| 384 | $settings = self::settings($config); |
| 385 | |
| 386 | if (empty($settings)) { |
| 387 | return false; |
| 388 | } |
| 389 | if (!self::isInitialized($config)) { |
| 390 | return false; |
| 391 | } |
| 392 | $key = self::$_engines[$config]->key($key); |
| 393 | |
| 394 | if (!$key || !is_integer($offset) || $offset < 0) { |
| 395 | return false; |
| 396 | } |
| 397 | $success = self::$_engines[$config]->decrement($settings['prefix'] . $key, $offset); |
| 398 | self::set(null, $config); |
| 399 | return $success; |
| 400 | } |
| 401 | |
| 402 | /** |
| 403 | * Delete a key from the cache. |
| 404 | * |
| 405 | * ### Usage: |
| 406 | * |
| 407 | * Deleting from the active cache configuration. |
| 408 | * |
| 409 | * `Cache::delete('my_data');` |
| 410 | * |
| 411 | * Deleting from a specific cache configuration. |
| 412 | * |
| 413 | * `Cache::delete('my_data', 'long_term');` |
| 414 | * |
| 415 | * @param string $key Identifier for the data |
| 416 | * @param string $config name of the configuration to use. Defaults to 'default' |
| 417 | * @return boolean True if the value was successfully deleted, false if it didn't exist or couldn't be removed |
| 418 | */ |
| 419 | public static function delete($key, $config = 'default') { |
| 420 | $settings = self::settings($config); |
| 421 | |
| 422 | if (empty($settings)) { |
| 423 | return false; |
| 424 | } |
| 425 | if (!self::isInitialized($config)) { |
| 426 | return false; |
| 427 | } |
| 428 | $key = self::$_engines[$config]->key($key); |
| 429 | if (!$key) { |
| 430 | return false; |
| 431 | } |
| 432 | |
| 433 | $success = self::$_engines[$config]->delete($settings['prefix'] . $key); |
| 434 | self::set(null, $config); |
| 435 | return $success; |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * Delete all keys from the cache. |
| 440 | * |
| 441 | * @param boolean $check if true will check expiration, otherwise delete all |
| 442 | * @param string $config name of the configuration to use. Defaults to 'default' |
| 443 | * @return boolean True if the cache was successfully cleared, false otherwise |
| 444 | */ |
| 445 | public static function clear($check = false, $config = 'default') { |
| 446 | if (!self::isInitialized($config)) { |
| 447 | return false; |
| 448 | } |
| 449 | $success = self::$_engines[$config]->clear($check); |
| 450 | self::set(null, $config); |
| 451 | return $success; |
| 452 | } |
| 453 | |
| 454 | /** |
| 455 | * Check if Cache has initialized a working config for the given name. |
| 456 | * |
| 457 | * @param string $config name of the configuration to use. Defaults to 'default' |
| 458 | * @return boolean Whether or not the config name has been initialized. |
| 459 | */ |
| 460 | public static function isInitialized($config = 'default') { |
| 461 | if (Configure::read('Cache.disable')) { |
| 462 | return false; |
| 463 | } |
| 464 | return isset(self::$_engines[$config]); |
| 465 | } |
| 466 | |
| 467 | /** |
| 468 | * Return the settings for the named cache engine. |
| 469 | * |
| 470 | * @param string $name Name of the configuration to get settings for. Defaults to 'default' |
| 471 | * @return array list of settings for this engine |
| 472 | * @see Cache::config() |
| 473 | */ |
| 474 | public static function settings($name = 'default') { |
| 475 | if (!empty(self::$_engines[$name])) { |
| 476 | return self::$_engines[$name]->settings(); |
| 477 | } |
| 478 | return array(); |
| 479 | } |
| 480 | |
| 481 | } |
| 482 | |
| 483 | |
| 484 |