File size: 6.49Kb
<?php
/**
* Smarty Internal Plugin
*
* @package Smarty
* @subpackage Cacher
*/
/**
* Cache Handler API
*
* @package Smarty
* @subpackage Cacher
* @author Rodney Rehm
*/
abstract class Smarty_CacheResource
{
/**
* resource types provided by the core
*
* @var array
*/
protected static $sysplugins = array('file' => 'smarty_internal_cacheresource_file.php',);
/**
* populate Cached Object with meta data from Resource
*
* @param Smarty_Template_Cached $cached cached object
* @param Smarty_Internal_Template $_template template object
*
* @return void
*/
abstract public function populate(Smarty_Template_Cached $cached, Smarty_Internal_Template $_template);
/**
* populate Cached Object with timestamp and exists from Resource
*
* @param Smarty_Template_Cached $cached
*
* @return void
*/
abstract public function populateTimestamp(Smarty_Template_Cached $cached);
/**
* Read the cached template and process header
*
* @param Smarty_Internal_Template $_template template object
* @param Smarty_Template_Cached $cached cached object
* @param boolean $update flag if called because cache update
*
* @return boolean true or false if the cached content does not exist
*/
abstract public function process(Smarty_Internal_Template $_template, Smarty_Template_Cached $cached = null,
$update = false);
/**
* Write the rendered template output to cache
*
* @param Smarty_Internal_Template $_template template object
* @param string $content content to cache
*
* @return boolean success
*/
abstract public function writeCachedContent(Smarty_Internal_Template $_template, $content);
/**
* Read cached template from cache
*
* @param Smarty_Internal_Template $_template template object
*
* @return string content
*/
abstract function readCachedContent(Smarty_Internal_Template $_template);
/**
* Return cached content
*
* @param Smarty_Internal_Template $_template template object
*
* @return null|string
*/
public function getCachedContent(Smarty_Internal_Template $_template)
{
if ($_template->cached->handler->process($_template)) {
ob_start();
$unifunc = $_template->cached->unifunc;
$unifunc($_template);
return ob_get_clean();
}
return null;
}
/**
* Empty cache
*
* @param Smarty $smarty Smarty object
* @param integer $exp_time expiration time (number of seconds, not timestamp)
*
* @return integer number of cache files deleted
*/
abstract public function clearAll(Smarty $smarty, $exp_time = null);
/**
* Empty cache for a specific template
*
* @param Smarty $smarty Smarty object
* @param string $resource_name template name
* @param string $cache_id cache id
* @param string $compile_id compile id
* @param integer $exp_time expiration time (number of seconds, not timestamp)
*
* @return integer number of cache files deleted
*/
abstract public function clear(Smarty $smarty, $resource_name, $cache_id, $compile_id, $exp_time);
/**
* @param Smarty $smarty
* @param Smarty_Template_Cached $cached
*
* @return bool|null
*/
public function locked(Smarty $smarty, Smarty_Template_Cached $cached)
{
// theoretically locking_timeout should be checked against time_limit (max_execution_time)
$start = microtime(true);
$hadLock = null;
while ($this->hasLock($smarty, $cached)) {
$hadLock = true;
if (microtime(true) - $start > $smarty->locking_timeout) {
// abort waiting for lock release
return false;
}
sleep(1);
}
return $hadLock;
}
/**
* Check is cache is locked for this template
*
* @param Smarty $smarty
* @param Smarty_Template_Cached $cached
*
* @return bool
*/
public function hasLock(Smarty $smarty, Smarty_Template_Cached $cached)
{
// check if lock exists
return false;
}
/**
* Lock cache for this template
*
* @param Smarty $smarty
* @param Smarty_Template_Cached $cached
*
* @return bool
*/
public function acquireLock(Smarty $smarty, Smarty_Template_Cached $cached)
{
// create lock
return true;
}
/**
* Unlock cache for this template
*
* @param Smarty $smarty
* @param Smarty_Template_Cached $cached
*
* @return bool
*/
public function releaseLock(Smarty $smarty, Smarty_Template_Cached $cached)
{
// release lock
return true;
}
/**
* Load Cache Resource Handler
*
* @param Smarty $smarty Smarty object
* @param string $type name of the cache resource
*
* @throws SmartyException
* @return Smarty_CacheResource Cache Resource Handler
*/
public static function load(Smarty $smarty, $type = null)
{
if (!isset($type)) {
$type = $smarty->caching_type;
}
// try smarty's cache
if (isset($smarty->_cache[ 'cacheresource_handlers' ][ $type ])) {
return $smarty->_cache[ 'cacheresource_handlers' ][ $type ];
}
// try registered resource
if (isset($smarty->registered_cache_resources[ $type ])) {
// do not cache these instances as they may vary from instance to instance
return $smarty->_cache[ 'cacheresource_handlers' ][ $type ] = $smarty->registered_cache_resources[ $type ];
}
// try sysplugins dir
if (isset(self::$sysplugins[ $type ])) {
$cache_resource_class = 'Smarty_Internal_CacheResource_' . ucfirst($type);
return $smarty->_cache[ 'cacheresource_handlers' ][ $type ] = new $cache_resource_class();
}
// try plugins dir
$cache_resource_class = 'Smarty_CacheResource_' . ucfirst($type);
if ($smarty->loadPlugin($cache_resource_class)) {
return $smarty->_cache[ 'cacheresource_handlers' ][ $type ] = new $cache_resource_class();
}
// give up
throw new SmartyException("Unable to load cache resource '{$type}'");
}
}