<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.5.4
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Cache\Engine;
use APCUIterator;
use Cake\Cache\CacheEngine;
/**
* APCu storage engine for cache
*/
class ApcuEngine extends CacheEngine
{
/**
* Contains the compiled group names
* (prefixed with the global configuration prefix)
*
* @var string[]
*/
protected $_compiledGroupNames = [];
/**
* Initialize the Cache Engine
*
* Called automatically by the cache frontend
*
* @param array $config array of setting for the engine
* @return bool True if the engine has been successfully initialized, false if not
*/
public function init(array $config = [])
{
if (!extension_loaded('apcu')) {
return false;
}
return parent::init($config);
}
/**
* Write data for key into cache
*
* @param string $key Identifier for the data
* @param mixed $value Data to be cached
* @return bool True if the data was successfully cached, false on failure
* @link https://secure.php.net/manual/en/function.apcu-store.php
*/
public function write($key, $value)
{
$key = $this->_key($key);
$duration = $this->_config['duration'];
return apcu_store($key, $value, $duration);
}
/**
* Read a key from the cache
*
* @param string $key Identifier for the data
* @return mixed The cached data, or false if the data doesn't exist,
* has expired, or if there was an error fetching it
* @link https://secure.php.net/manual/en/function.apcu-fetch.php
*/
public function read($key)
{
$key = $this->_key($key);
return apcu_fetch($key);
}
/**
* Increments the value of an integer cached key
*
* @param string $key Identifier for the data
* @param int $offset How much to increment
* @return int|false New incremented value, false otherwise
* @link https://secure.php.net/manual/en/function.apcu-inc.php
*/
public function increment($key, $offset = 1)
{
$key = $this->_key($key);
return apcu_inc($key, $offset);
}
/**
* Decrements the value of an integer cached key
*
* @param string $key Identifier for the data
* @param int $offset How much to subtract
* @return int|false New decremented value, false otherwise
* @link https://secure.php.net/manual/en/function.apcu-dec.php
*/
public function decrement($key, $offset = 1)
{
$key = $this->_key($key);
return apcu_dec($key, $offset);
}
/**
* Delete a key from the cache
*
* @param string $key Identifier for the data
* @return bool True if the value was successfully deleted, false if it didn't exist or couldn't be removed
* @link https://secure.php.net/manual/en/function.apcu-delete.php
*/
public function delete($key)
{
$key = $this->_key($key);
return apcu_delete($key);
}
/**
* Delete all keys from the cache. This will clear every cache config using APC.
*
* @param bool $check If true, nothing will be cleared, as entries are removed
* from APC as they expired. This flag is really only used by FileEngine.
* @return bool True Returns true.
* @link https://secure.php.net/manual/en/function.apcu-cache-info.php
* @link https://secure.php.net/manual/en/function.apcu-delete.php
*/
public function clear($check)
{
if ($check) {
return true;
}
if (class_exists(APCUIterator::class, false)) {
$iterator = new APCUIterator(
'/^' . preg_quote($this->_config['prefix'], '/') . '/',
APC_ITER_NONE
);
apcu_delete($iterator);
return true;
}
$cache = apcu_cache_info(); // Raises warning by itself already
foreach ($cache['cache_list'] as $key) {
if (strpos($key['info'], $this->_config['prefix']) === 0) {
apcu_delete($key['info']);
}
}
return true;
}
/**
* Write data for key into cache if it doesn't exist already.
* If it already exists, it fails and returns false.
*
* @param string $key Identifier for the data.
* @param mixed $value Data to be cached.
* @return bool True if the data was successfully cached, false on failure.
* @link https://secure.php.net/manual/en/function.apcu-add.php
*/
public function add($key, $value)
{
$key = $this->_key($key);
$duration = $this->_config['duration'];
return apcu_add($key, $value, $duration);
}
/**
* Returns the `group value` for each of the configured groups
* If the group initial value was not found, then it initializes
* the group accordingly.
*
* @return string[]
* @link https://secure.php.net/manual/en/function.apcu-fetch.php
* @link https://secure.php.net/manual/en/function.apcu-store.php
*/
public function groups()
{
if (empty($this->_compiledGroupNames)) {
foreach ($this->_config['groups'] as $group) {
$this->_compiledGroupNames[] = $this->_config['prefix'] . $group;
}
}
$success = false;
$groups = apcu_fetch($this->_compiledGroupNames, $success);
if ($success && count($groups) !== count($this->_config['groups'])) {
foreach ($this->_compiledGroupNames as $group) {
if (!isset($groups[$group])) {
$value = 1;
if (apcu_store($group, $value) === false) {
$this->warning(
sprintf('Failed to store key "%s" with value "%s" into APCu cache.', $group, $value)
);
}
$groups[$group] = $value;
}
}
ksort($groups);
}
$result = [];
$groups = array_values($groups);
foreach ($this->_config['groups'] as $i => $group) {
$result[] = $group . $groups[$i];
}
return $result;
}
/**
* Increments the group value to simulate deletion of all keys under a group
* old values will remain in storage until they expire.
*
* @param string $group The group to clear.
* @return bool success
* @link https://secure.php.net/manual/en/function.apcu-inc.php
*/
public function clearGroup($group)
{
$success = false;
apcu_inc($this->_config['prefix'] . $group, 1, $success);
return $success;
}
}