php 使用redis锁限制并发访问类示例

<?php/** * Redis锁操作类 * Date:  2016-06-30 * Author: fdipzone * Ver:  1.0 * * Func: * public lock  获取锁 * public unlock 释放锁 * private connect 连接 */class RedisLock { // class start  private $_config;  private $_redis;  /**   * 初始化   * @param Array $config redis连接设定   */  public function __construct($config=array()){    $this->_config = $config;    $this->_redis = $this->connect();  }  /**   * 获取锁   * @param String $key  锁标识   * @param Int   $expire 锁过期时间   * @return Boolean   */  public function lock($key, $expire=5){    $is_lock = $this->_redis->setnx($key, time()+$expire);    // 不能获取锁    if(!$is_lock){      // 判断锁是否过期      $lock_time = $this->_redis->get($key);      // 锁已过期，删除锁，重新获取      if(time()>$lock_time){        $this->unlock($key);        $is_lock = $this->_redis->setnx($key, time()+$expire);      }    }    return $is_lock? true : false;  }  /**   * 释放锁   * @param String $key 锁标识   * @return Boolean   */  public function unlock($key){    return $this->_redis->del($key);  }  /**   * 创建redis连接   * @return Link   */  private function connect(){    try{      $redis = new Redis();      $redis->connect($this->_config['host'],$this->_config['port'],$this->_config['timeout'],$this->_config['reserved'],$this->_config['retry_interval']);      if(empty($this->_config['auth'])){        $redis->auth($this->_config['auth']);      }      $redis->select($this->_config['index']);    }catch(RedisException $e){      throw new Exception($e->getMessage());      return false;    }    return $redis;  }} // class end?>

<?phprequire 'RedisLock.class.php';$config = array(  'host' => 'localhost',  'port' => 6379,  'index' => 0,  'auth' => '',  'timeout' => 1,  'reserved' => NULL,  'retry_interval' => 100,);// 创建redislock对象$oRedisLock = new RedisLock($config);// 定义锁标识$key = 'mylock';// 获取锁$is_lock = $oRedisLock->lock($key, 10);if($is_lock){  echo 'get lock success<br>';  echo 'do sth..<br>';  sleep(5);  echo 'success<br>';  $oRedisLock->unlock($key);// 获取锁失败}else{  echo 'request too frequently<br>';}?>