redis 分布式锁

<?php

use Illuminate\Support\Facades\Redis;

class RedisLock
{
    const NOT_EXISTS              = 'NX';
    const MILLISECOND_EXPIRE_TIME = 'PX';
    // key 持有时间（millisecond）
    const EXPIRE_TIME = 500;
    // 等待超时时间
    const TIME_OUT = 1000;

    private static $token;

    // 解锁 LUA 脚本
    const LUA_SCRIPT_RELEASE_LOCK = '
        if (ARGV[1] == redis.call("GET", KEYS[1])) then
            return redis.call("DEL", KEYS[1]);
        end;
        return 0;
    ';

    /**
     * @param     $key
     * @param int $expire
     *
     * @return bool
     * @throws \Exception
     */
    public static function lock($key, $expire = self::EXPIRE_TIME)
    {
        $start       = self::msectime();
        self::$token = self::createToken();

        // 获取锁失败，再一定时间内循环尝试获取
        while (1) {
            $result = Redis::set($key, self::$token, self::MILLISECOND_EXPIRE_TIME, $expire, self::NOT_EXISTS);
            if ('OK' === (string)$result) {
                return true;
            }

            $diff = self::msectime() - $start;
            if ($diff >= self::TIME_OUT) {
                return false;
            }

            usleep(100);

        }
    }


    /**
     * @param $key
     *
     * @return bool
     */
    public static function unlock($key)
    {
        return (bool)Redis::eval(self::LUA_SCRIPT_RELEASE_LOCK, 1, $key, self::$token);
    }


    /**
     * @return string
     * @throws \Exception
     */
    public static function createToken()
    {
        if (PHP_VERSION_ID >= 70000 && function_exists('random_bytes')) {
            return getmypid() . '_' . bin2hex(random_bytes(16));
        }
        return getmypid() . '_' . uniqid() . rand(10000, 99999);
    }

    /**
     * 返回当前的毫秒时间戳
     *
     * @return float
     */
    public static function  msectime() {
        list($msec, $sec) = explode(' ', microtime());
        $msectime = (float)sprintf('%.0f', (floatval($msec) + floatval($sec)) * 1000);
        return $msectime;
    }
}

使用：

<?php

$key = 'redis_lock:'.$response['order_no'];
$lock = RedisLock::lock($key);
if(! $lock) {
    Log::error("order lock: ".$key);
    return;
}

try {

    sleep(10);
   
} catch (\Throwable $throwable) {
    Log::error(CommonService::getExceptionMsg($throwable));
} finally {
    // 处理完任务释放锁
    RedisLock::unlock($key);
}