[ * 'class' => 'yii\web\CacheSession', * // 'cache' => 'mycache', * ] * ``` * * @property-read bool $useCustomStorage Whether to use custom storage. * * @author Qiang Xue * @since 2.0 */ class CacheSession extends Session { /** * @var CacheInterface|array|string the cache object or the application component ID of the cache object. * The session data will be stored using this cache object. * * After the CacheSession object is created, if you want to change this property, * you should only assign it with a cache object. * * Starting from version 2.0.2, this can also be a configuration array for creating the object. */ public $cache = 'cache'; /** * Initializes the application component. */ public function init() { parent::init(); $this->cache = Instance::ensure($this->cache, 'yii\caching\CacheInterface'); } /** * Returns a value indicating whether to use custom session storage. * This method overrides the parent implementation and always returns true. * @return bool whether to use custom storage. */ public function getUseCustomStorage() { return true; } /** * Session open handler. * @internal Do not call this method directly. * @param string $savePath session save path * @param string $sessionName session name * @return bool whether session is opened successfully */ public function openSession($savePath, $sessionName) { if ($this->getUseStrictMode()) { $id = $this->getId(); if (!$this->cache->exists($this->calculateKey($id))) { //This session id does not exist, mark it for forced regeneration $this->_forceRegenerateId = $id; } } return parent::openSession($savePath, $sessionName); } /** * Session read handler. * @internal Do not call this method directly. * @param string $id session ID * @return string the session data */ public function readSession($id) { $data = $this->cache->get($this->calculateKey($id)); return $data === false ? '' : $data; } /** * Session write handler. * @internal Do not call this method directly. * @param string $id session ID * @param string $data session data * @return bool whether session write is successful */ public function writeSession($id, $data) { if ($this->getUseStrictMode() && $id === $this->_forceRegenerateId) { //Ignore write when forceRegenerate is active for this id return true; } return $this->cache->set($this->calculateKey($id), $data, $this->getTimeout()); } /** * Session destroy handler. * @internal Do not call this method directly. * @param string $id session ID * @return bool whether session is destroyed successfully */ public function destroySession($id) { $cacheId = $this->calculateKey($id); if ($this->cache->exists($cacheId) === false) { return true; } return $this->cache->delete($cacheId); } /** * Generates a unique key used for storing session data in cache. * @param string $id session variable name * @return mixed a safe cache key associated with the session variable name */ protected function calculateKey($id) { return [__CLASS__, $id]; } }