<?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 3.0.0
* @filesource
*/
defined('BASEPATH') OR exit('No direct script access allowed');

/**
* CodeIgniter Redis Caching Class
*
* @package CodeIgniter
* @subpackage Libraries
* @category Core
* @author Anton Lindqvist <[email protected]>
* @link
*/
class CI_Cache_redis extends CI_Driver
{
/**
* Default config
*
* @static
* @var array
*/
protected static $_default_config = array(
'socket_type' => 'tcp',
'host' => '127.0.0.1',
'password' => NULL,
'port' => 6379,
'timeout' => 0
);

/**
* Redis connection
*
* @var Redis
*/
protected $_redis;

/**
* An internal cache for storing keys of serialized values.
*
* @var array
*/
protected $_serialized = array();

/**
* del()/delete() method name depending on phpRedis version
*
* @var string
*/
protected static $_delete_name;

/**
* sRem()/sRemove() method name depending on phpRedis version
*
* @var string
*/
protected static $_sRemove_name;

// ------------------------------------------------------------------------

/**
* Class constructor
*
* Setup Redis
*
* Loads Redis config file if present. Will halt execution
* if a Redis connection can't be established.
*
* @return void
* @see Redis::connect()
*/
public function __construct()
{
if ( ! $this->is_supported())
{
log_message('error', 'Cache: Failed to create Redis object; extension not loaded?');
return;
}

if ( ! isset(static::$_delete_name, static::$_sRemove_name))
{
if (version_compare(phpversion('redis'), '5', '>='))
{
static::$_delete_name = 'del';
static::$_sRemove_name = 'sRem';
}
else
{
static::$_delete_name = 'delete';
static::$_sRemove_name = 'sRemove';
}
}

$CI =& get_instance();

if ($CI->config->load('redis', TRUE, TRUE))
{
$config = array_merge(self::$_default_config, $CI->config->item('redis'));
}
else
{
$config = self::$_default_config;
}

$this->_redis = new Redis();

try
{
if ($config['socket_type'] === 'unix')
{
$success = $this->_redis->connect($config['socket']);
}
else // tcp socket
{
$success = $this->_redis->connect($config['host'], $config['port'], $config['timeout']);
}

if ( ! $success)
{
log_message('error', 'Cache: Redis connection failed. Check your configuration.');
}

if (isset($config['password']) && ! $this->_redis->auth($config['password']))
{
log_message('error', 'Cache: Redis authentication failed.');
}
}
catch (RedisException $e)
{
log_message('error', 'Cache: Redis connection refused ('.$e->getMessage().')');
}
}

// ------------------------------------------------------------------------

/**
* Get cache
*
* @param string $key Cache ID
* @return mixed
*/
public function get($key)
{
$value = $this->_redis->get($key);

if ($value !== FALSE && $this->_redis->sIsMember('_ci_redis_serialized', $key))
{
return unserialize($value);
}

return $value;
}

// ------------------------------------------------------------------------

/**
* Save cache
*
* @param string $id Cache ID
* @param mixed $data Data to save
* @param int $ttl Time to live in seconds
* @param bool $raw Whether to store the raw value (unused)
* @return bool TRUE on success, FALSE on failure
*/
public function save($id, $data, $ttl = 60, $raw = FALSE)
{
if (is_array($data) OR is_object($data))
{
if ( ! $this->_redis->sIsMember('_ci_redis_serialized', $id) && ! $this->_redis->sAdd('_ci_redis_serialized', $id))
{
return FALSE;
}

isset($this->_serialized[$id]) OR $this->_serialized[$id] = TRUE;
$data = serialize($data);
}
else
{
$this->_redis->{static::$_sRemove_name}('_ci_redis_serialized', $id);
}

return $this->_redis->set($id, $data, $ttl);
}

// ------------------------------------------------------------------------

/**
* Delete from cache
*
* @param string $key Cache key
* @return bool
*/
public function delete($key)
{
if ($this->_redis->{static::$_delete_name}($key) !== 1)
{
return FALSE;
}

$this->_redis->{static::$_sRemove_name}('_ci_redis_serialized', $key);

return TRUE;
}

// ------------------------------------------------------------------------

/**
* 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 $this->_redis->incrBy($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 $this->_redis->decrBy($id, $offset);
}

// ------------------------------------------------------------------------

/**
* Clean cache
*
* @return bool
* @see Redis::flushDB()
*/
public function clean()
{
return $this->_redis->flushDB();
}

// ------------------------------------------------------------------------

/**
* Get cache driver info
*
* @param string $type Not supported in Redis.
* Only included in order to offer a
* consistent cache API.
* @return array
* @see Redis::info()
*/
public function cache_info($type = NULL)
{
return $this->_redis->info();
}

// ------------------------------------------------------------------------

/**
* Get cache metadata
*
* @param string $key Cache key
* @return array
*/
public function get_metadata($key)
{
$value = $this->get($key);

if ($value !== FALSE)
{
return array(
'expire' => time() + $this->_redis->ttl($key),
'data' => $value
);
}

return FALSE;
}

// ------------------------------------------------------------------------

/**
* Check if Redis driver is supported
*
* @return bool
*/
public function is_supported()
{
return extension_loaded('redis');
}

// ------------------------------------------------------------------------

/**
* Class destructor
*
* Closes the connection to Redis if present.
*
* @return void
*/
public function __destruct()
{
if ($this->_redis)
{
$this->_redis->close();
}
}
}