Ticket #313: Cache_Memcache.php

<?php defined('SYSPATH') or die('No direct script access.');
/**
 * Memcache-based Cache driver.
 *
 * @package    Cache
 * @author     Kohana Team
 * @copyright  (c) 2007 Kohana Team
 * @license    http://kohanaphp.com/license.html
 */
class Cache_Memcache_Driver implements Cache_Driver {

    private $_mc = null;
    private $flag = null;
    
    public function __construct()
    {
    if ( ! extension_loaded('memcache')) 
        throw new Kohana_Exception('cache.extension_not_loaded', 'memcache');

        $this->_mc =& new Memcache;                                                                                                                                      
        $this->flag = (Config::item('cache_memcache.compression')) ? MEMCACHE_COMPRESSED : 0;

        foreach ( Config::item('cache_memcache.servers') as $server)
    {
            if ( ! isset($server['persistent'])) 
                $server['persistent'] = false;
            
            if ( ! isset($server['port'])) 
                $server['port'] = 11211;
        
            if( ! $this->_mc->addServer($server['host'], $server['port'], $server['persistent'])) 
                Log::add('error', 'Cache: Connection failed -> '.$server['host']);
        }    
    }

    public function find($tag)
    {
    return false;
    }

    public function get($id)
    {
        return $this->_mc->get($id);
    }

    public function set($id, $data, $tags, $expiration)
    {
    $result = $this->_mc->set($id, $data, $this->flag, $expiration);

    if(count($tags) > 0)
        Log::add('error', 'tags are unsupported by the Memcache driver');

    return $result;
    }

    public function delete($id, $tag = FALSE)
    {
        if($id === TRUE)
    {
        return $this->_mc->flush();
    }
    elseif ($tag == FALSE)
    {
        return $this->_mc->delete($id);
    }
    else
    {
        return true;
    }
    }

    public function delete_expired()
    {
    return true;
    }
}// End Cache Memcache Driver