system/libraries/Cache/Cache.php
<?php
/**
* CodeIgniter
*
* An open source application development framework for PHP
*
* This content is released under the MIT License (MIT)
*
* Copyright (c) 2019 - 2022, CodeIgniter Foundation
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* @package CodeIgniter
* @author EllisLab Dev Team
* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
* @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
* @copyright Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
* @license https://opensource.org/licenses/MIT MIT License
* @link https://codeigniter.com
* @since Version 2.0.0
* @filesource
*/
defined('BASEPATH') OR exit('No direct script access allowed');
/**
* CodeIgniter Caching Class
*
* @package CodeIgniter
* @subpackage Libraries
* @category Core
* @author EllisLab Dev Team
* @link
*/
class CI_Cache extends CI_Driver_Library {
/**
* Valid cache drivers
*
* @var array
*/
protected $valid_drivers = array(
'apc',
'apcu',
'dummy',
'file',
'memcached',
'redis',
'wincache'
);
/**
* Path of cache files (if file-based cache)
*
* @var string
*/
protected $_cache_path = NULL;
/**
* Reference to the driver
*
* @var mixed
*/
protected $_adapter = 'dummy';
/**
* Fallback driver
*
* @var string
*/
protected $_backup_driver = 'dummy';
/**
* Cache key prefix
*
* @var string
*/
public $key_prefix = '';
/**
* Constructor
*
* Initialize class properties based on the configuration array.
*
* @param array $config = array()
* @return void
*/
public function __construct($config = array())
{
isset($config['adapter']) && $this->_adapter = $config['adapter'];
isset($config['backup']) && $this->_backup_driver = $config['backup'];
isset($config['key_prefix']) && $this->key_prefix = $config['key_prefix'];
// If the specified adapter isn't available, check the backup.
if ( ! $this->is_supported($this->_adapter))
{
if ( ! $this->is_supported($this->_backup_driver))
{
// Backup isn't supported either. Default to 'Dummy' driver.
log_message('error', 'Cache adapter "'.$this->_adapter.'" and backup "'.$this->_backup_driver.'" are both unavailable. Cache is now using "Dummy" adapter.');
$this->_adapter = 'dummy';
}
else
{
// Backup is supported. Set it to primary.
log_message('debug', 'Cache adapter "'.$this->_adapter.'" is unavailable. Falling back to "'.$this->_backup_driver.'" backup adapter.');
$this->_adapter = $this->_backup_driver;
}
}
}
// ------------------------------------------------------------------------
/**
* Get
*
* Look for a value in the cache. If it exists, return the data
* if not, return FALSE
*
* @param string $id
* @return mixed value matching $id or FALSE on failure
*/
public function get($id)
{
return $this->{$this->_adapter}->get($this->key_prefix.$id);
}
// ------------------------------------------------------------------------
/**
* Cache Save
*
* @param string $id Cache ID
* @param mixed $data Data to store
* @param int $ttl Cache TTL (in seconds)
* @param bool $raw Whether to store the raw value
* @return bool TRUE on success, FALSE on failure
*/
public function save($id, $data, $ttl = 60, $raw = FALSE)
{
return $this->{$this->_adapter}->save($this->key_prefix.$id, $data, $ttl, $raw);
}
// ------------------------------------------------------------------------
/**
* Delete from Cache
*
* @param string $id Cache ID
* @return bool TRUE on success, FALSE on failure
*/
public function delete($id)
{
return $this->{$this->_adapter}->delete($this->key_prefix.$id);
}
// ------------------------------------------------------------------------
/**
* Increment a raw value
*
* @param string $id Cache ID
* @param int $offset Step/value to add
* @return mixed New value on success or FALSE on failure
*/
public function increment($id, $offset = 1)
{
return $this->{$this->_adapter}->increment($this->key_prefix.$id, $offset);
}
// ------------------------------------------------------------------------
/**
* Decrement a raw value
*
* @param string $id Cache ID
* @param int $offset Step/value to reduce by
* @return mixed New value on success or FALSE on failure
*/
public function decrement($id, $offset = 1)
{
return $this->{$this->_adapter}->decrement($this->key_prefix.$id, $offset);
}
// ------------------------------------------------------------------------
/**
* Clean the cache
*
* @return bool TRUE on success, FALSE on failure
*/
public function clean()
{
return $this->{$this->_adapter}->clean();
}
// ------------------------------------------------------------------------
/**
* Cache Info
*
* @param string $type = 'user' user/filehits
* @return mixed array containing cache info on success OR FALSE on failure
*/
public function cache_info($type = 'user')
{
return $this->{$this->_adapter}->cache_info($type);
}
// ------------------------------------------------------------------------
/**
* Get Cache Metadata
*
* @param string $id key to get cache metadata on
* @return mixed cache item metadata
*/
public function get_metadata($id)
{
return $this->{$this->_adapter}->get_metadata($this->key_prefix.$id);
}
// ------------------------------------------------------------------------
/**
* Is the requested driver supported in this environment?
*
* @param string $driver The driver to test
* @return array
*/
public function is_supported($driver)
{
static $support;
if ( ! isset($support, $support[$driver]))
{
$support[$driver] = $this->{$driver}->is_supported();
}
return $support[$driver];
}
// ------------------------------------------------------------------------
/**
* Get currently loaded driver
*
* @return string
*/
public function get_loaded_driver()
{
return $this->_adapter;
}
}