cakephp2-php8/cake/libs/cache.php

<?php
/* SVN FILE: $Id$ */

/**
 * Caching for Cake.
 *
 *
 *
 * PHP versions 4 and 5
 *
 * CakePHP :  Rapid Development Framework <http://www.cakephp.org/>
 * Copyright (c) 2006, Cake Software Foundation, Inc.
 *                     1785 E. Sahara Avenue, Suite 490-204
 *                     Las Vegas, Nevada 89104
 *
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 *
 * @filesource
 * @copyright    Copyright (c) 2006, Cake Software Foundation, Inc.
 * @link         http://www.cakefoundation.org/projects/info/cakephp CakePHP Project
 * @package      cake
 * @subpackage   cake.cake.libs
 * @since        CakePHP v 0.2.9
 * @version      $Revision$
 * @modifiedby   $LastChangedBy$
 * @lastmodified $Date$
 * @license      http://www.opensource.org/licenses/mit-license.php The MIT License
 */


/**
 * Included libraries.
 *
 */
if(!class_exists('Model'))
{
    uses(DS.'model'.DS.'model');
}
/**
 * Caching for Cake.
 *
 *
 *
 * @package    cake
 * @subpackage cake.cake.libs
 * @since      CakePHP v 0.2.9
 */
class Cache extends Model {

/**
 * Identifier. Either an MD5 string or NULL.
 *
 * @var string
 */
    var $id = null;

/**
 * Content container for cache data.
 *
 * @var unknown_type
 */
    var $data = null;

/**
 * Content to be cached.
 *
 * @var unknown_type
 */
    var $for_caching = null;

/**
 * Name of the database table used for caching.
 *
 * @var string
 */
    var $useTable = 'cache';

/**
 * Constructor. Generates an md5'ed id for internal use. Calls the constructor on Model as well.
 *
 * @param unknown_type $id
 */
    function __construct ($id)
    {
        $this->id = (md5($id));
        parent::__construct($this->id);
    }

/**
 * Returns this object's id after setting it. If called without parameters the current object's id is returned.
 *
 * @param unknown_type $id
 * @return unknown
 */
    function id ($id=null)
    {
        if (!$id) return $this->id;
        return ($this->id = $id);
    }

/**
 * Store given content in cache database.
 *
 * @param string $content         Content to keep in cache.
 * @param int $keep_for         Number of seconds to keep data in cache.
 * @return boolean                Success
 */
    function remember ($content, $keep_for=CACHE_PAGES_FOR)
    {
        $data = addslashes($this->for_caching.$content);
        $expire = date("Y-m-d H:i:s",time()+($keep_for>0? $keep_for: 999999999));
        return $this->query("REPLACE {$this->useTable} (id,data,expire) VALUES ('{$this->id}', '{$data}', '{$expire}')");
    }

/**
 * Returns content from the Cache object itself, if the Cache object has a non-empty data property.
 * Else from the database cache.
 *
 * @return unknown
 */
    function restore()
    {
        if (empty($this->data['data']))
        return $this->find("id='{$this->id}' AND expire>NOW()");

        return $this->data['data'];
    }

/**
 * Returns true if the cache data property has current (non-stale) content for given id.
 *
 * @return boolean
 */
    function has()
    {
        return is_array($this->data = $this->find("id='{$this->id}' AND expire>NOW()"));
    }

/**
 * Appends $string to the for_caching property of the Cache object.
 *
 * @param string $string
 */
    function append($string)
    {
        $this->for_caching .= $string;
    }

/**
 * Clears the cache database table.
 *
 * @return unknown
 */
    function clear()
    {
        return $this->query("DELETE FROM {$this->useTable}");
    }
}

?>