<?php
/**
* This class extends Cache_Lite and offers a cache system driven by a master file
*
* With this class, cache validity is only dependent of a given file. Cache files
* are valid only if they are older than the master file. It's a perfect way for
* caching templates results (if the template file is newer than the cache, cache
* must be rebuild...) or for config classes...
* There are some examples in the 'docs/examples' file
* Technical choices are described in the 'docs/technical' file
*
* @package Cache_Lite
* @version $Id: File.php,v 1.4 2009/03/07 12:55:39 tacker Exp $
* @author Fabien MARTY <[email protected]>
*/
require_once('cacher/Lite.php');
class Cache_Lite_File extends Cache_Lite
{
// --- Private properties ---
/**
* Complete path of the file used for controlling the cache lifetime
*
* @var string $_masterFile
*/
var $_masterFile = '';
/**
* Masterfile mtime
*
* @var int $_masterFile_mtime
*/
var $_masterFile_mtime = 0;
// --- Public methods ----
/**
* Constructor
*
* $options is an assoc. To have a look at availables options,
* see the constructor of the Cache_Lite class in 'Cache_Lite.php'
*
* Comparing to Cache_Lite constructor, there is another option :
* $options = array(
* (...) see Cache_Lite constructor
* 'masterFile' => complete path of the file used for controlling the cache lifetime(string)
* );
*
* @param array $options options
* @access public
*/
function Cache_Lite_File($options = array(NULL))
{
$options['lifetime'] = 0;
$this->Cache_Lite($options);
if (isset($options['masterFile'])) {
$this->_masterFile = $options['masterFile'];
} else {
return $this->raiseError('Cache_Lite_File : masterFile option must be set !');
}
if (!($this->_masterFile_mtime = @filemtime($this->_masterFile))) {
return $this->raiseError('Cache_Lite_File : Unable to read masterFile : '.$this->_masterFile, -3);
}
}
/**
* Test if a cache is available and (if yes) return it
*
* @param string $id cache id
* @param string $group name of the cache group
* @param boolean $doNotTestCacheValidity if set to true, the cache validity won't be tested
* @return string data of the cache (else : false)
* @access public
*/
function get($id, $group = 'default', $doNotTestCacheValidity = false)
{
if ($data = parent::get($id, $group, true)) {
if ($filemtime = $this->lastModified()) {
if ($filemtime > $this->_masterFile_mtime) {
return $data;
}
}
}
return false;
}
}
?>