/cake/libs/cache.php
PHP | 535 lines | 225 code | 46 blank | 264 comment | 51 complexity | d8025290432c29ea79452d1ac77d3d93 MD5 | raw file
- <?php
- /**
- * Caching for CakePHP.
- *
- *
- * PHP Version 5.x
- *
- * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
- * Copyright 2005-2009, Cake Software Foundation, Inc. (http://cakefoundation.org)
- *
- * Licensed under The MIT License
- * Redistributions of files must retain the above copyright notice.
- *
- * @copyright Copyright 2005-2009, Cake Software Foundation, Inc. (http://cakefoundation.org)
- * @link http://cakephp.org CakePHP(tm) Project
- * @package cake
- * @subpackage cake.cake.libs
- * @since CakePHP(tm) v 1.2.0.4933
- * @license MIT License (http://www.opensource.org/licenses/mit-license.php)
- */
- /**
- * Caching for CakePHP.
- *
- * @package cake
- * @subpackage cake.cake.libs
- */
- class Cache {
- /**
- * Cache configuration stack
- * Keeps the permanent/default settings for each cache engine.
- * These settings are used to reset the engines after temporary modification.
- *
- * @var array
- * @access private
- */
- private static $__config = array();
- /**
- * Holds name of the current configuration name being used.
- *
- * @var array
- * @access private
- */
- private static $__name = 'default';
- /**
- * Whether to reset the settings with the next call to Cache::set();
- *
- * @var array
- * @access private
- */
- private static $__reset = false;
- /**
- * Engine instances keyed by configuration name.
- *
- * @var array
- * @access protected
- */
- protected $_engines = array();
- /**
- * Returns a singleton instance
- *
- * @return object
- * @access public
- * @static
- */
- /*
- private function &getInstance() {
- static $instance = array();
- if (!$instance) {
- $instance[0] = new Cache();
- }
- return $instance[0];
- }
- */
- /**
- * Set the cache configuration to use. config() can
- * both create new configurations, return the settings for already configured
- * configurations. It also sets the 'default' configuration to use for subsequent
- * operations.
- *
- * To create a new configuration:
- *
- * `Cache::config('my_config', array('engine' => 'File', 'path' => TMP));`
- *
- * To get the settings for a configuration, and set it as the currently selected configuration
- *
- * `Cache::config('default');`
- *
- * @see app/config/core.php for configuration settings
- * @param string $name Name of the configuration
- * @param array $settings Optional associative array of settings passed to the engine
- * @return array(engine, settings) on success, false on failure
- * @access public
- * @static
- */
- public function config($name = null, $settings = array()) {
- if (is_array($name)) {
- $settings = $name;
- }
- if ($name === null || !is_string($name)) {
- $name = self::$__name;
- }
- $current = array();
- if (isset(self::$__config[$name])) {
- $current = self::$__config[$name];
- }
- if (!empty($settings)) {
- self::$__config[$name] = array_merge($current, $settings);
- }
- if (empty(self::$__config[$name]['engine'])) {
- return false;
- }
- self::$__name = $name;
- $engine = self::$__config[$name]['engine'];
- if (!isset(self::$_engines[$name])) {
- self::_buildEngine($name);
- $settings = self::$__config[$name] = self::settings($name);
- } elseif ($settings = self::set(self::$__config[$name])) {
- self::$__config[$name] = $settings;
- }
- return compact('engine', 'settings');
- }
- /**
- * Finds and builds the instance of the required engine class.
- *
- * @param string $name Name of the config array that needs an engine instance built
- * @return void
- * @access protected
- */
- protected function _buildEngine($name) {
- $config = self::$__config[$name];
- list($plugin, $class) = pluginSplit($config['engine']);
- $cacheClass = $class . 'Engine';
- if (!class_exists($cacheClass) && self::__loadEngine($class, $plugin) === false) {
- return false;
- }
- $cacheClass = $class . 'Engine';
- self::$_engines[$name] = new $cacheClass();
- if (self::$_engines[$name]->init($config)) {
- if (time() % self::$_engines[$name]->settings['probability'] === 0) {
- self::$_engines[$name]->gc();
- }
- return true;
- }
- return false;
- }
- /**
- * Returns an array containing the currently configured Cache settings.
- *
- * @return array
- * @access public
- */
- public function configured() {
- return array_keys(self::$__config);
- }
- /**
- * Drops a cache engine. Deletes the cache configuration information
- * If the deleted configuration is the last configuration using an certain engine,
- * the Engine instance is also unset.
- *
- * @param string $name A currently configured cache config you wish to remove.
- * @return boolen success of the removal, returns false when the config does not exist.
- * @access public
- */
- public function drop($name) {
- if (!isset(self::$__config[$name])) {
- return false;
- }
- unset(self::$__config[$name]);
- unset(self::$_engines[$name]);
- return true;
- }
- /**
- * Tries to find and include a file for a cache engine and returns object instance
- *
- * @param $name Name of the engine (without 'Engine')
- * @return mixed $engine object or null
- * @access private
- */
- private function __loadEngine($name, $plugin = null) {
- if ($plugin) {
- return App::import('Lib', $plugin . '.cache' . DS . $name, false);
- } else {
- $app = App::import('Lib', 'cache' . DS . $name, false);
- if (!$app) {
- require LIBS . 'cache' . DS . strtolower($name) . '.php';
- }
- return true;
- }
- }
- /**
- * Temporarily change settings to current config options. if no params are passed, resets settings if needed
- * Cache::write() will reset the configuration changes made
- *
- * @param mixed $settings Optional string for simple name-value pair or array
- * @param string $value Optional for a simple name-value pair
- * @return array of settings
- * @access public
- * @static
- */
- public function set($settings = array(), $value = null) {
- if (!isset(self::$__config[self::$__name])) {
- return false;
- }
- $name = self::$__name;
- if (!empty($settings)) {
- self::$__reset = true;
- }
- if (self::$__reset === true) {
- if (empty($settings)) {
- self::$__reset = false;
- $settings = self::$__config[$name];
- } else {
- if (is_string($settings) && $value !== null) {
- $settings = array($settings => $value);
- }
- $settings = array_merge(self::$__config[self::$__name], $settings);
- if (isset($settings['duration']) && !is_numeric($settings['duration'])) {
- $settings['duration'] = strtotime($settings['duration']) - time();
- }
- }
- self::$_engines[$name]->settings = $settings;
- }
- return self::settings($name);
- }
- /**
- * Garbage collection
- *
- * Permanently remove all expired and deleted data
- *
- * @return void
- * @access public
- * @static
- */
- public function gc() {
- self::$_engines[self::$__name]->gc();
- }
- /**
- * Write data for key into cache
- *
- * @param string $key Identifier for the data
- * @param mixed $value Data to be cached - anything except a resource
- * @param string $config Optional - string configuration name
- * @return boolean True if the data was successfully cached, false on failure
- * @access public
- * @static
- */
- public function write($key, $value, $config = null) {
- if (!$config) {
- $config = self::$__name;
- }
- $settings = self::settings($config);
- if (empty($settings)) {
- return null;
- }
- if (!self::isInitialized($config)) {
- return false;
- }
- $key = self::$_engines[$config]->key($key);
- if (!$key || is_resource($value) || $settings['duration'] < 1) {
- return false;
- }
- $success = self::$_engines[$config]->write($settings['prefix'] . $key, $value, $settings['duration']);
- self::set();
- return $success;
- }
- /**
- * Read a key from the cache
- *
- * @param string $key Identifier for the data
- * @param string $config name of the configuration to use
- * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it
- * @access public
- * @static
- */
- public function read($key, $config = null) {
- if (!$config) {
- $config = self::$__name;
- }
- $settings = self::settings($config);
- if (empty($settings)) {
- return null;
- }
- if (!self::isInitialized($config)) {
- return false;
- }
- $key = self::$_engines[$config]->key($key);
- if (!$key) {
- return false;
- }
- $success = self::$_engines[$config]->read($settings['prefix'] . $key);
- if ($config !== null && $config !== self::$__name) {
- self::set();
- }
- return $success;
- }
- /**
- * Delete a key from the cache
- *
- * @param string $key Identifier for the data
- * @param string $config name of the configuration to use
- * @return boolean True if the value was succesfully deleted, false if it didn't exist or couldn't be removed
- * @access public
- * @static
- */
- public function delete($key, $config = null) {
- if (!$config) {
- $config = self::$__name;
- }
- $settings = self::settings($config);
- if (empty($settings)) {
- return null;
- }
- if (!self::isInitialized($config)) {
- return false;
- }
- $key = self::$_engines[$config]->key($key);
- if (!$key) {
- return false;
- }
- $success = self::$_engines[$config]->delete($settings['prefix'] . $key);
- self::set();
- return $success;
- }
- /**
- * Delete all keys from the cache
- *
- * @param boolean $check if true will check expiration, otherwise delete all
- * @param string $config name of the configuration to use
- * @return boolean True if the cache was succesfully cleared, false otherwise
- * @access public
- * @static
- */
- public function clear($check = false, $config = null) {
- if (!$config) {
- $config = self::$__name;
- }
- $settings = self::settings($config);
- if (empty($settings)) {
- return null;
- }
- if (!self::isInitialized($config)) {
- return false;
- }
- $success = self::$_engines[$config]->clear($check);
- self::set();
- return $success;
- }
- /**
- * Check if Cache has initialized a working config for the given name.
- *
- * @param string $engine Name of the engine
- * @param string $config Name of the configuration setting
- * @return bool
- * @access public
- * @static
- */
- public function isInitialized($name = null) {
- if (Configure::read('Cache.disable')) {
- return false;
- }
- if (!$name && isset(self::$__config[self::$__name])) {
- $name = self::$__name;
- }
- return isset(self::$_engines[$name]);
- }
- /**
- * Return the settings for current cache engine. If no name is supplied the settings
- * for the 'active default' configuration will be returned. To set the 'active default'
- * configuration use `Cache::config()`
- *
- * @param string $engine Name of the configuration to get settings for.
- * @return array list of settings for this engine
- * @see Cache::config()
- * @access public
- * @static
- */
- public function settings($name = null) {
- if (!$name && isset(self::$__config[self::$__name])) {
- $name = self::$__name;
- }
- if (!empty(self::$_engines[$name])) {
- return self::$_engines[$name]->settings();
- }
- return array();
- }
- }
- /**
- * Storage engine for CakePHP caching
- *
- * @package cake
- * @subpackage cake.cake.libs
- */
- class CacheEngine {
- /**
- * settings of current engine instance
- *
- * @var int
- * @access public
- */
- protected $settings = array();
- /**
- * Initialize the cache engine
- *
- * Called automatically by the cache frontend
- *
- * @param array $params Associative array of parameters for the engine
- * @return boolean True if the engine has been succesfully initialized, false if not
- * @access public
- */
- public function init($settings = array()) {
- $this->settings = array_merge(array('prefix' => 'cake_', 'duration'=> 3600, 'probability'=> 100), $this->settings, $settings);
- if (!is_numeric($this->settings['duration'])) {
- $this->settings['duration'] = strtotime($this->settings['duration']) - time();
- }
- return true;
- }
- /**
- * Garbage collection
- *
- * Permanently remove all expired and deleted data
- *
- * @access public
- */
- public function gc() {
- }
- /**
- * Write value for a key into cache
- *
- * @param string $key Identifier for the data
- * @param mixed $value Data to be cached
- * @param mixed $duration How long to cache the data, in seconds
- * @return boolean True if the data was succesfully cached, false on failure
- * @access public
- */
- public function write($key, &$value, $duration) {
- trigger_error(sprintf(__('Method write() not implemented in %s', true), get_class($this)), E_USER_ERROR);
- }
- /**
- * Read a key from the cache
- *
- * @param string $key Identifier for the data
- * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it
- * @access public
- */
- public function read($key) {
- trigger_error(sprintf(__('Method read() not implemented in %s', true), get_class($this)), E_USER_ERROR);
- }
- /**
- * Delete a key from the cache
- *
- * @param string $key Identifier for the data
- * @return boolean True if the value was succesfully deleted, false if it didn't exist or couldn't be removed
- * @access public
- */
- public function delete($key) {
- }
- /**
- * Delete all keys from the cache
- *
- * @param boolean $check if true will check expiration, otherwise delete all
- * @return boolean True if the cache was succesfully cleared, false otherwise
- * @access public
- */
- public function clear($check) {
- }
- /**
- * Cache Engine settings
- *
- * @return array settings
- * @access public
- */
- public function settings() {
- return $this->settings;
- }
- /**
- * generates a safe key
- *
- * @param string $key the key passed over
- * @return mixed string $key or false
- * @access public
- */
- public function key($key) {
- if (empty($key)) {
- return false;
- }
- return Inflector::underscore(str_replace(array(DS, '/', '.'), '_', strval($key)));
- }
- }
- ?>