Sg_Session_SaveHandler_Cache.php

<?php
class Sg_Session_SaveHandler_Cache implements Zend_Session_SaveHandler_Interface {
	protected $_cache;
	/**
	 * Session lifetime
	 *
	 * @var int
	 */
	protected $_lifetime = false;
	/**
	 * Session save path
	 *
	 * @var string
	 */
	protected $_sessionSavePath;
	
	/**
	 * Session name
	 *
	 * @var string
	 */
	protected $_sessionName;
	
	public function __construct(Zend_Cache_Core $cacheBackend, $options = array()) {
		$this->_cache = $cacheBackend;
		if ($options instanceof Zend_Config) {
			$options = $options->toArray ();
		}
		foreach ($options as $key => $value) {
			switch (strtolower($key)) {
				case 'lifetime':
					$this->setLifetime($value);
					break;
			}
		}
		if ($this->_lifetime === false) {
			$this->setLifetime();
		}
	}
	/**
	 * Close Session (for override)
	 * 
	 * @return boolean
	 */
	public function close() {
		return true;
	}
	/**
	 * Destroy a Session
	 * 
	 * @param	string	$id
	 */
	public function destroy($id) {
		return ( boolean ) $this->_cache
			->remove ( $id );
	}
	
	/**
	 * Runs Garbage Collection
	 * 
	 * @param	int	$maxlifetime <unused>
	 * @return void
	 */
	public function gc($maxlifetime) {
		$this->_cache
			->clean ( 'old' );
	}
	/**
	 * Opens Session Handler (good for file caching, not useful here)
	 * 
	 * @return boolean
	 */
	public function open($save_path, $name) {
		$this->_sessionSavePath = $save_path;
		$this->_sessionName = $name;
		
		return true;
	}
	
    /**
     * Read session data
     *
     * @param string $id
     * @return string
     */
	public function read($id) {
		return $this->_cache->load($id, false, true);
	

	}
	
    /**
     * Write session data
     *
     * @param string $id
     * @param string $data
     * @return boolean
     */
	public function write($id, $data) {
		return (bool) $this->_cache->save($data, $id, 'Session', $this->_lifetime);
	}
	
	public function setLifetime($lifetime = null) {
		if (0 > $lifetime) {
			/**
			 * @see Zend_Session_SaveHandler_Exception
			 */
			require_once 'Zend/Session/SaveHandler/Exception.php';
			throw new Zend_Session_SaveHandler_Exception ();
		} else if (empty ( $lifetime )) {
			$this->_lifetime = ( int ) ini_get ( 'session.gc_maxlifetime' );
		} else {
			$this->_lifetime = ( int ) $lifetime;
		}
	}
	
	public function getLifetime() {
		return $this->_lifetime;
	}

}