<?php
/**
* CodeIgniter
*
* An open source application development framework for PHP
*
* This content is released under the MIT License (MIT)
*
* Copyright (c) 2014-2019 British Columbia Institute of Technology
* Copyright (c) 2019 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 CodeIgniter Dev Team
* @copyright 2019 CodeIgniter Foundation
* @license https://opensource.org/licenses/MIT MIT License
* @link https://codeigniter.com
* @since Version 4.0.0
* @filesource
*/
namespace CodeIgniter\Cache\Handlers;
use CodeIgniter\Cache\CacheInterface;
use CodeIgniter\Exceptions\CriticalError;
/**
* Redis cache handler
*/
class RedisHandler implements CacheInterface
{
/**
* Prefixed to all cache names.
*
* @var string
*/
protected $prefix;
/**
* Default config
*
* @static
* @var array
*/
protected $config = [
'host' => '127.0.0.1',
'password' => null,
'port' => 6379,
'timeout' => 0,
'database' => 0,
];
/**
* Redis connection
*
* @var Redis
*/
protected $redis;
//--------------------------------------------------------------------
/**
* Constructor.
*
* @param type $config
* @throws type
*/
public function __construct($config)
{
$config = (array)$config;
$this->prefix = $config['prefix'] ?? '';
if (! empty($config))
{
$this->config = array_merge($this->config, $config['redis']);
}
}
/**
* Class destructor
*
* Closes the connection to Memcache(d) if present.
*/
public function __destruct()
{
if ($this->redis)
{
$this->redis->close();
}
}
//--------------------------------------------------------------------
/**
* Takes care of any handler-specific setup that must be done.
*/
public function initialize()
{
$config = $this->config;
$this->redis = new \Redis();
// Try to connect to Redis, if an issue occurs throw a CriticalError exception,
// so that the CacheFactory can attempt to initiate the next cache handler.
try
{
// Note:: If Redis is your primary cache choice, and it is "offline", every page load will end up been delayed by the timeout duration.
// I feel like some sort of temporary flag should be set, to indicate that we think Redis is "offline", allowing us to bypass the timeout for a set period of time.
if (! $this->redis->connect($config['host'], ($config['host'][0] === '/' ? 0 : $config['port']), $config['timeout']))
{
// Note:: I'm unsure if log_message() is necessary, however I'm not 100% comfortable removing it.
log_message('error', 'Cache: Redis connection failed. Check your configuration.');
throw new CriticalError('Cache: Redis connection failed. Check your configuration.');
}
if (isset($config['password']) && ! $this->redis->auth($config['password']))
{
log_message('error', 'Cache: Redis authentication failed.');
throw new CriticalError('Cache: Redis authentication failed.');
}
if (isset($config['database']) && ! $this->redis->select($config['database']))
{
log_message('error', 'Cache: Redis select database failed.');
throw new CriticalError('Cache: Redis select database failed.');
}
}
catch (\RedisException $e)
{
// $this->redis->connect() can sometimes throw a RedisException.
// We need to convert the exception into a CriticalError exception and throw it.
throw new CriticalError('Cache: RedisException occurred with message (' . $e->getMessage() . ').');
}
}
//--------------------------------------------------------------------
/**
* Attempts to fetch an item from the cache store.
*
* @param string $key Cache item name
*
* @return mixed
*/
public function get(string $key)
{
$key = $this->prefix . $key;
$data = $this->redis->hMGet($key, ['__ci_type', '__ci_value']);
if (! isset($data['__ci_type'], $data['__ci_value']) || $data['__ci_value'] === false)
{
return null;
}
switch ($data['__ci_type'])
{
case 'array':
case 'object':
return unserialize($data['__ci_value']);
case 'boolean':
case 'integer':
case 'double': // Yes, 'double' is returned and NOT 'float'
case 'string':
case 'NULL':
return settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null;
case 'resource':
default:
return null;
}
}
//--------------------------------------------------------------------
/**
* Saves an item to the cache store.
*
* @param string $key Cache item name
* @param mixed $value The data to save
* @param integer $ttl Time To Live, in seconds (default 60)
*
* @return mixed
*/
public function save(string $key, $value, int $ttl = 60)
{
$key = $this->prefix . $key;
switch ($data_type = gettype($value))
{
case 'array':
case 'object':
$value = serialize($value);
break;
case 'boolean':
case 'integer':
case 'double': // Yes, 'double' is returned and NOT 'float'
case 'string':
case 'NULL':
break;
case 'resource':
default:
return false;
}
if (! $this->redis->hMSet($key, ['__ci_type' => $data_type, '__ci_value' => $value]))
{
return false;
}
elseif ($ttl)
{
$this->redis->expireAt($key, time() + $ttl);
}
return true;
}
//--------------------------------------------------------------------
/**
* Deletes a specific item from the cache store.
*
* @param string $key Cache item name
*
* @return mixed
*/
public function delete(string $key)
{
$key = $this->prefix . $key;
return ($this->redis->del($key) === 1);
}
//--------------------------------------------------------------------
/**
* Performs atomic incrementation of a raw stored value.
*
* @param string $key Cache ID
* @param integer $offset Step/value to increase by
*
* @return mixed
*/
public function increment(string $key, int $offset = 1)
{
$key = $this->prefix . $key;
return $this->redis->hIncrBy($key, 'data', $offset);
}
//--------------------------------------------------------------------
/**
* Performs atomic decrementation of a raw stored value.
*
* @param string $key Cache ID
* @param integer $offset Step/value to increase by
*
* @return mixed
*/
public function decrement(string $key, int $offset = 1)
{
$key = $this->prefix . $key;
return $this->redis->hIncrBy($key, 'data', -$offset);
}
//--------------------------------------------------------------------
/**
* Will delete all items in the entire cache.
*
* @return mixed
*/
public function clean()
{
return $this->redis->flushDB();
}
//--------------------------------------------------------------------
/**
* Returns information on the entire cache.
*
* The information returned and the structure of the data
* varies depending on the handler.
*
* @return mixed
*/
public function getCacheInfo()
{
return $this->redis->info();
}
//--------------------------------------------------------------------
/**
* Returns detailed information about the specific item in the cache.
*
* @param string $key Cache item name.
*
* @return mixed
*/
public function getMetaData(string $key)
{
$key = $this->prefix . $key;
$value = $this->get($key);
if ($value !== null)
{
$time = time();
return [
'expire' => $time + $this->redis->ttl($key),
'mtime' => $time,
'data' => $value,
];
}
return null;
}
//--------------------------------------------------------------------
/**
* Determines if the driver is supported on this system.
*
* @return boolean
*/
public function isSupported(): bool
{
return extension_loaded('redis');
}
//--------------------------------------------------------------------
}
Jim Parry