Cache_redis.php - Array/Object Support, Approach 2. See https://github.com/EllisLab/CodeIgniter/pull/3181

Cache_redis.php

<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.2.4 or newer
 *
 * NOTICE OF LICENSE
 *
 * Licensed under the Open Software License version 3.0
 *
 * This source file is subject to the Open Software License (OSL 3.0) that is
 * bundled with this package in the files license.txt / license.rst.  It is
 * also available through the world wide web at this URL:
 * http://opensource.org/licenses/OSL-3.0
 * If you did not receive a copy of the license and are unable to obtain it
 * through the world wide web, please send an email to
 * licensing@ellislab.com so we can send you a copy immediately.
 *
 * @package		CodeIgniter
 * @author		EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
 * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
 * @link		http://codeigniter.com
 * @since		Version 3.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * CodeIgniter Redis Caching Class
 *
 * @package	   CodeIgniter
 * @subpackage Libraries
 * @category   Core
 * @author	   Anton Lindqvist <anton@qvister.se>
 * @link
 */
class CI_Cache_redis extends CI_Driver
{
	/**
	 * A key-suffix for distinguishing serialized values.
	 */
	const KEY_PREFIX_FOR_SERIALIZATION = '_ci_redis_serialized:';

	/**
	 * 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;

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

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

		if ($value === FALSE)
		{
			$value = $this->_redis->get(self::KEY_PREFIX_FOR_SERIALIZATION.$key);

			if ($value !== FALSE)
			{
				return unserialize($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))
		{
			$this->_redis->delete($id);

			$data = serialize($data);
			$id = self::KEY_PREFIX_FOR_SERIALIZATION.$id;
		}

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

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

	/**
	 * Delete from cache
	 *
	 * @param	string	Cache key
	 * @return	bool
	 */
	public function delete($key)
	{
		return ($this->_redis->delete($key) OR $this->_redis->delete(self::KEY_PREFIX_FOR_SERIALIZATION.$key));
	}

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

	/**
	 * 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, $offset = 1)
	{
		if ($this->_redis->exists(self::KEY_PREFIX_FOR_SERIALIZATION.$id))
		{
			return FALSE;
		}
		
		return $this->_redis->incr($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, $offset = 1)
	{
		if ($this->_redis->exists(self::KEY_PREFIX_FOR_SERIALIZATION.$id))
		{
			return FALSE;
		}
		
		return $this->_redis->decr($id, $offset);
	}

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

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

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

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

		if ($value === FALSE)
		{
			$key = self::KEY_PREFIX_FOR_SERIALIZATION.$key;
			$value = $this->_redis->get($key);

			if ($value === FALSE)
			{
			    return FALSE;
			}

			$value = unserialize($value);
		}

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

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

	/**
	 * Check if Redis driver is supported
	 *
	 * @return	bool
	 */
	public function is_supported()
	{
		if (extension_loaded('redis'))
		{
			return $this->_setup_redis();
		}
		else
		{
			log_message('debug', 'The Redis extension must be loaded to use Redis cache.');
			return FALSE;
		}
	}

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

	/**
	 * Setup Redis config and connection
	 *
	 * Loads Redis config file if present. Will halt execution
	 * if a Redis connection can't be established.
	 *
	 * @return	bool
	 * @see		Redis::connect()
	 */
	protected function _setup_redis()
	{
		$config = array();
		$CI =& get_instance();

		if ($CI->config->load('redis', TRUE, TRUE))
		{
			$config += $CI->config->item('redis');
		}

		$config = array_merge(self::$_default_config, $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('debug', 'Cache: Redis connection refused. Check the config.');
				return FALSE;
			}
		}
		catch (RedisException $e)
		{
			log_message('debug', 'Cache: Redis connection refused ('.$e->getMessage().')');
			return FALSE;
		}

		if (isset($config['password']))
		{
			$this->_redis->auth($config['password']);
		}

		return TRUE;
	}

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

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

}

/* End of file Cache_redis.php */
/* Location: ./system/libraries/Cache/drivers/Cache_redis.php */

Redis_test.php

<?php defined('BASEPATH') OR exit('No direct script access allowed');

class Redis_test extends CI_Controller {

    public function index() {

        echo '<br />';

        echo 'CodeIgniter 3.0-dev: Redis Caching Driver Test.';
        echo '<br />';
        echo '<br />';

        echo 'phpredis version: '.@phpversion('redis');
        echo '<br />';
        echo '<br />';
        echo '<hr />';

        echo '<br />';

        echo 'Making a native Redis class instance: ';
        echo '<br />';

        $redis = new Redis() or die('Can not load redis.'); 
        $redis->connect('127.0.0.1'); 

        $redis_server_info = $redis->info();
        $redis_server_version = $redis_server_info['redis_version'];

        echo 'Redis server version: '.$redis_server_version;

        echo '<br />';
        echo '<br />';

        echo 'Loading CodeIgniter\'s cache with redis driver.';

        echo '<br />';
        echo '<br />';

        $this->load->driver('cache', array('adapter' => 'redis'));

        // Let us see whwther they work.

        echo 'The following value should increment on every page reload.';

        echo '<br />';

        $this->cache->increment('test_key_1');
        var_dump($this->cache->get('test_key_1'));

        echo '<br />';
        echo '<br />';

        echo 'The following value should decrement on every page reload.';

        echo '<br />';

        $this->cache->decrement('test_key_2');
        var_dump($this->cache->get('test_key_2'));

        echo '<br />';
        echo '<br />';

        echo 'Saving and reading an ordinary string.';

        echo '<br />';

        $this->cache->save('test_key_3', '--- An ordinary string ---');
        var_dump($this->cache->get('test_key_3'));

        echo '<br />';

        echo '<hr />';

        echo '<br />';

        echo 'Making an array of objects ($records variable).';

        echo '<br />';

        $records = json_decode('[{"id":1},{"id":2},{"id":3}]');
        var_dump($records);

        echo '<br />';
        echo '<br />';

        echo 'Saving $records within cache under "records" key.';

        echo '<br />';

        $this->cache->save('records', $records);

        echo '<hr />';
        echo '<br />';

        echo 'Reading "records" and showing the result.';

        echo '<br />';

        $records_read = $this->cache->get('records', $records);
        var_dump($records_read);

        echo '<br />';
        echo '<br />';

        echo 'Reading metadata of "records" and showing the result.';

        echo '<br />';

        $records_read = $this->cache->get_metadata('records');
        var_dump($records_read);

        echo '<br />';
        echo '<hr />';
        echo '<br />';

        echo 'Deleting "records" and showing the result.';

        echo '<br />';

        $result_delete = $this->cache->delete('records', $records);
        var_dump($result_delete);

        echo '<br />';
        echo '<br />';

        echo 'Deleting "records" again and showing the result.';

        echo '<br />';

        $result_delete = $this->cache->delete('records', $records);
        var_dump($result_delete);

        echo '<br />';
        echo '<br />';

        echo 'Reading deleted "records" and showing the result.';

        echo '<br />';

        $records_read = $this->cache->get('records', $records);
        var_dump($records_read);

        echo '<br />';
        echo '<br />';

        echo 'Reading metadata of non-existing "records" and showing the result.';

        echo '<br />';

        $records_read = $this->cache->get_metadata('records');
        var_dump($records_read);

        echo '<br />';
        echo '<hr />';
        echo '<br />';

        exit;
    }

}