Codeigniter的Redis使用

一、Redis的配置和简单使用1：

1. ./config/redis.php:

<?php
$config['redis_host']     = '127.0.0.1';
$config['redis_port']     = '6379';
$config['redis_isopen']   = true;

2. ./config/config.php:

require_once(APPPATH . "config/redis.php");

3. ./application/libraries/RedisService.php:

<?php
class RedisService{
    public $CI;
    public $redis;
    public function __construct()
    {
        $this->CI = & get_instance();
        $this->CI->load->driver('cache', array('adapter' => 'redis'));
        $this->redis = $this->CI->cache->get_redis();
        $this->cache = $this->CI->cache;
    }
}

4../system/libraries/Cache/Cache.php:

//修改：
protected $valid_drivers 	= array(
		'cache_apc', 'cache_file', 'cache_memcached', 'cache_dummy', 'cache_redis'
);

//添加：
public function get_redis(){
	if($this->_adapter == 'redis'){
		return $this->{$this->_adapter}->get_redis();
	}
	return false;
}

5. ./system/libraries/Cache/drivers/Cache_redis.php:

<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2016, British Columbia Institute of Technology
 *
 * 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 - 2016, British Columbia Institute of Technology (http://bcit.ca/)
 * @license	http://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 <anton@qvister.se>
 * @link
 */
class CI_Cache_redis extends CI_Driver{
	/**
	 * Default config
	 *
	 * @static
	 * @var	array
	 */
	protected static $_default_config = array(
		'host' => '10.19.108.196',
		'password' => 'datu@com',
		'port' => 6379,
		'timeout' => 0
	);

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

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

	/**
	 * 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;
		}

		$CI =& get_instance();

		// 读取配置文件
		$config_all         = get_config();
		$config['host']     = $config_all['redis_host'];
		$config['port']     = $config_all['redis_port'];
		// $config['password'] = $config_all['redis_pwd'];
		$config['timeout']  = 0;

		$this->_redis = new Redis();

		try{
			if ( ! $this->_redis->connect($config['host'], ($config['host'][0] === '/' ? 0 : $config['port']), $config['timeout'])){
				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){
		$data = $this->_redis->hMGet($key, array('__ci_type', '__ci_value'));

		if (!$data['__ci_type']) $data['__ci_type'] = 'integer';

		if ( ! isset($data['__ci_type'], $data['__ci_value']) OR $data['__ci_value'] === FALSE){
			return FALSE;
		}

		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']
					: FALSE;
			case 'resource':
			default:
				return FALSE;
		}
	}

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

	/**
	 * 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, $raw = FALSE){
		switch ($data_type = gettype($data)){
			case 'array':
			case 'object':
				$data = serialize($data);
				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 ( ! $this->_redis->hMSet($id, array('__ci_type' => $data_type, '__ci_value' => $data))){
			return FALSE;
		}elseif ($ttl){
			$this->_redis->expireAt($id, time() + $ttl);
		}

		return TRUE;
	}

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

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

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

	/**
	 * 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 $this->_redis->hIncrBy($id, '__ci_value', $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 $this->_redis->hIncrBy($id, '__ci_value', -$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');
	}

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

	/**
	 * return redis
	 *
	 * @return	redis
	 */
	public function get_redis(){
		return $this->_redis;
	}

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

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

6. 控制器中就可以使用啦：

//初始化：
$this->load->library('redisservice');
$this->redis = new RedisService;

//使用:
$this->redis->redis->set('name', 'chenjian');
$this->redis->redis->get('name');

二、Redis的实际使用2：

对于一个数据的请求，一般情况下controller中接收参数$this->input->get('date'),然后通过参数请求model里面的方法从而得到数据返回，这一层可以做缓存：

～示例～：

1. 控制器中：****

$this->load->model("user"); //初始化
$this->load->library( 'cache_mgr' ); //引用cache_mgr库文件
function user_list(){
	$age = $this->input->get('age');
	$key = sprintf('2017-01-12-%s', $age); //利用日期+年龄组成一个key。
/*
get_cache有四个参数：get_cache(key, model里面的方法, 参数数组, 缓存的时长),且get_cache方法不仅仅可以取缓存，如果没有缓存就执行model里面的方法，并且缓存。
*/
	$data = $this->cache_mgr->get_cache($key, array($this->user, 'get_user'), array('age' => $age), 60 * 60);
}

1. library里面的库文件：

<?php
class cache_mgr{
	protected static $redis;
	protected $host;
	protected $port;
	protected $pwd;
	protected $is_open;

	private $_config = array();

	public function __construct(){
		$this->_config = get_config();
		$this->host    = $this->_config['redis_host'];
		$this->port    = $this->_config['redis_port'];
		$this->is_open = $this->_config['redis_isopen'];
		$this->pwd     = $this->_config['redis_pwd'];

		if (! $this->is_open) {
			self::$redis = null;
		} elseif (! self::$redis)
			$this->connect ();
	}

	/**
	 *
	 * @return cache_mgr
	 */
	static function get_instance(){
		$ci = get_instance ();
		$var = __CLASS__;
		return $ci->$var;
	}

	/**
	 * 返回当前rediscache服务器是否有效
	 *
	 * @return boolean
	 */
	public function is_connected(){
		return self::$redis ? true : false;
	}

	/**
	 * 连接rediscache
	 */
	private function connect(){
		self::$redis = new Redis();
		if (! @self::$redis->connect ( $this->host, $this->port )) {
			self::$redis = null;
			// echo "not redis";
		} else {
			self::$redis->auth($this->pwd);
		}
	}

	/**
	 * 前端代码读写缓存。所有前端代码只能用这个方法来写缓存
	 *
	 * @param string $key 键值，可为数组array(group值,键值)，group值可以用做批量删除
	 * @param callback $function
	 * @param array $params
	 * @param int $expire
	 * @return mixed
	 */
	public function get_cache($key, $function, $params = array(), $expire = 0){
		// 如果缓存没有开
		if (! self::$redis) {
			return call_user_func_array ( $function, $params );
		}
		$rs = $this->get ( $key );
		if (! $rs) {
			$rs = call_user_func_array ( $function, $params );
			if (! $rs) $expire = 5 * 60;
			$this->save( $key, $rs, $expire );
		}
		return $rs;
	}

	/**
	 * 要清除的缓存
	 *
	 * @param string $key
	 */
	public function clear($key){
		return self::$redis ? self::$redis->delete ( $key ) : false;
	}

	/**
	 * Get cache
	 *
	 * @param	string	$key	Cache ID
	 * @return	mixed
	 */
	public function get($key){
		$data = self::$redis->hMGet($key, array('__ci_value'));
		if ( ! isset($data['__ci_value']) OR $data['__ci_value'] === FALSE){
			return FALSE;
		}
		return unserialize($data['__ci_value']);
	}

	/**
	 * 生成缓存，通常用于后台
	 *
	 * @param string $key
	 * @param string $value
	 * @param int $ttl 过期秒数，为0时永不过期
	 * @return bool
	 */
	public function save($key, $value, $ttl = 60, $raw = FALSE){
		if ( ! self::$redis->hMSet($key, array('__ci_value' => serialize ($value)))){
			return FALSE;
		}elseif ($ttl){
			self::$redis->expireAt($key, time() + $ttl);
		}
		return TRUE;
	}

	/**
	 * 加法，只能对数值型缓存使用,对 key 的值做++操作,并返回
	 *
	 * @param string $key
	 * @param int $value
	 */
	public function increment($key, $offset = 1){
		return self::$redis ? self::$redis->hIncrBy($key, 'data', $offset) : false;
	}

	/**
	 * 减法，只能对数值型缓存使用,对 key 的值做--操作,并返回
	 *
	 * @param string $key
	 * @param int $value
	 */
	function decrement($key, $offset = 1){
		return self::$redis ? self::$redis->hIncrBy($key, 'data', -$offset) : false;
	}

	/**
	 * 关闭rides
	 *
	 * @param string $key
	 * @param int $value
	 */
	public function close(){
		if (self::$redis) {
			return self::$redis->close ();
			self::$redis = null;
		}
	}

}