Redis实现分布式锁（集群版）

1    if redis.call("get",KEYS[1]) == ARGV[1] then
2        return redis.call("del",KEYS[1])
3    else
4        return 0
5    end

  1class RedisLock
  2{
  3    /**
  4     * 获取锁
  5     * @param string $lock_name 锁名
  6     * @param int $acquire_time 重复请求次数
  7     * @param int $lock_timeout 请求超时时间
  8     * @return bool|string
  9     */
 10    public static function acquireLock($lock_name, $acquire_time = 3, $lock_timeout = 20)
 11    {
 12        $identifier = md5($_SERVER['REQUEST_TIME'] . mt_rand(1, 10000000));
 13        $lock_name = 'AGENT_ORDER_LOCK:' . $lock_name;
 14        $lock_timeout = intval(ceil($lock_timeout));
 15        $end_time = time() + $acquire_time;
 16        while (time() < $end_time) {
 17            $script = <<<luascript
 18                 local result = redis.call('setnx',KEYS[1],ARGV[1]);
 19                    if result == 1 then
 20                        redis.call('expire',KEYS[1],ARGV[2])
 21                        return 1
 22                    elseif redis.call('ttl',KEYS[1]) == -1 then
 23                       redis.call('expire',KEYS[1],ARGV[2])
 24                       return 0
 25                    end
 26                    return 0
 27luascript;
 28            $result = location_redis()->evaluate($script, array($lock_name, $identifier, $lock_timeout), 1);
 29            if ($result == '1') {
 30                return $identifier;
 31            }
 32            // 锁饥饿的问题。获取锁失败后，随机休息一段时间
 33            usleep(100000); //  函数延迟代码执行若干微秒
 34        }
 35        return false;
 36    }
 37
 38    /**
 39     * 释放锁
 40     * @param string $lock_name 锁名
 41     * @param string $identifier 获取锁返回的标识
 42     * @return bool
 43     */
 44    public static function releaseLock($lock_name, $identifier)
 45    {
 46        $lock_name = 'AGENT_ORDER_LOCK:' . $lock_name;
 47        while (true) {
 48            $script = <<<luascript
 49                local result = redis.call('get',KEYS[1]);
 50                if result == ARGV[1] then
 51                    if redis.call('del',KEYS[1]) == 1 then
 52                        return 1;
 53                    end
 54                end
 55                return 0
 56luascript;
 57            $result = location_redis()->evaluate($script, array($lock_name, $identifier), 1);
 58            if ($result == 1) {
 59                return true;
 60            }
 61            break;
 62        }
 63        //进程已经失去了锁
 64        return false;
 65    }
 66
 67    /**
 68     * 添加黑白名单
 69     * @param string $ip IP地址
 70     * @param bool $isWhite 是白名单，否则为黑
 71     * @return int
 72     */
 73    public function addBlackWhiteList($ip, $isWhite = true)
 74    {
 75        if($isWhite){
 76            $result = location_redis()->sAdd('IP_WHITE_LIST:AGENT',$ip);
 77        }else{
 78            $result = location_redis()->sAdd('IP_BLACK_LIST:AGENT',$ip);
 79        }
 80        return $result;
 81    }
 82
 83    /**
 84     * 获取远程服务端IP
 85     * @return array|false|null|string
 86     */
 87    public static function getRemoteIp()
 88    {
 89        if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
 90            $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
 91        } elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {
 92            $ip = $_SERVER['HTTP_CLIENT_IP'];
 93        } elseif (getenv('HTTP_X_FORWARDED_FOR')) {
 94            $ip = getenv('HTTP_X_FORWARED_FOR');
 95        } elseif (getenv('HTTP_CLIENT_IP')) {
 96            $ip = getenv('HTTP_CLIENT_IP');
 97        } elseif ($_SERVER['REMOTE_ADDR']) {
 98            $ip = $_SERVER['REMOTE_ADDR'];
 99        } else {
100            $ip = null;
101        }
102        Log::debug('[获取用户的IP]  '.$ip);
103        return $ip;
104    }
105}