Redis锁功能代码

<?php

class Rediss {
	private static  $_instance = null;
	private function __construct(){
		self::$_instance = new Redis();
		$config = [
			'host' => '127.0.0.1',
			'port' => 6379
		];
		self::$_instance->connect($config['host'],$config['port']);
		if(isset($config['password'])){
			self::$_instance->auth($config['password']);
		}
	}

	public static function instance(){
		if(!self::$_instance){
			 new self;
		}

		return self::$_instance;
	}

	private function __clone(){}
}





class ProcessRedisLock{
/**
     * redis key 前缀
     */
    const KEY_PREFIX = 'PROCESS_REDIS_LOCK:';

    /**
     * 默认超时时间（秒）
     */
    const DEFAULT_TIMEOUT = 5;

    /**
     * 最大超时时间（秒）
     */
    const MAX_TIMEOUT_SETTING = 60;

    /**
     * 随机数的最小值
     */
    const MIN_RAND_NUM = 0;

    /**
     * 随机数的最大值
     */
    const RAND_MAX_NUM = 100000;

    /**
     * 每次取锁间隔毫秒数1-1000000
     */
    const GET_LOCK_SLEEP_MICRO_SECONDS = 10;

    /**
     * @var mixed redis 实例
     */
    private $redisIns;

    /**
     * @var string 锁名
     */
    private $lockName;

    /**
     * @var int 超时时间,不可超过 self::MAX_TIMEOUT_SETTING
     */
    private $timeout;



	public function __construct($redisIns,$lockName,$timeout = self::DEFAULT_TIMEOUT){
        if (!$redisIns) {
            new Exception('The redis instance is empty');
        }

        if(!$lockName){
            throw new Exception('Lock name invalid');
        }

        // 校验超时时间
        $timeout = intval($timeout);
        if (!($timeout > 0 && $timeout <= self::MAX_TIMEOUT_SETTING)) {
            throw new Exception('The timeout interval is (0,' . self::MAX_TIMEOUT_SETTING . ']');
        }

        $this->redisIns = $redisIns;
        $this->lockName = $lockName;
        $this->timeout = $timeout;
	}


	   /**
     * 加锁
     * @return bool
     * @Date 2019/11/22
     */
    public function lock()
    {
        // redis key
        $key = $this->getRedisKey();


        // 唯一标志
        $id = $this->getId();

        // 超时时间
        $endTime = time() + $this->timeout;

        // 循环取锁
        while (time() < $endTime) {
            // 尝试加锁，若给定的 key 已经存在，则 SETNX 不做任何动作。
            if ($this->redisIns->setnx($key, $id)) {
                // 设置过期时间，防止程序异常退出没有解锁导致死锁
                $this->redisIns->expire($key, $this->timeout);
                // 返回唯一标志，用于解锁
                return $id;
            }
            usleep(self::GET_LOCK_SLEEP_MICRO_SECONDS);
        }

        return false;
    }


        /**
     * 解锁
     * @param string $id 唯一标志，加锁成功时返回
     * @return bool
     * @Date 2019/11/22
     */
    public function unlock($id)
    {
        $key = self::getRedisKey();

        // 如果锁的值与没有被修改
        if ($this->redisIns->get($key) == $id) {
            // 开始事务
            $this->redisIns->multi();
            // 释放该锁
            $this->redisIns->del($key);
            // 执行
            $this->redisIns->exec();
            return true;
        } else {
            return false;
        }
    }


      /**
     * 获取redis key
     * @return string
     * @Date 2019/11/22
     */
    public function getRedisKey()
    {
        return self::KEY_PREFIX . $this->lockName;
    }

    /**
     * 获取唯一标志位
     * @Date 2019/11/22
     */
    public function getId()
    {
        return uniqid(self::KEY_PREFIX) . mt_rand(self::MIN_RAND_NUM, self::RAND_MAX_NUM);
    }
}


class test {

	public function testAction()
    {
        $params = $this->getRequest()->getParams();
        $this->requestTask($params['queryName'], $params['handlerTime'], $params['lockName'], $params['timeout']);
    }

    // 模拟取锁、耗时操作、释放锁
    public function requestTask($queryName, $handlerTime, $lockName, $timeout)
    {
        try {
            // 获取redis实例
        	//$aa = Rediss::instance();
            $processRedisLock = new ProcessRedisLock(Rediss::instance(), $lockName, $timeout);

            $this->echoAndSaveInfo($queryName, "try to get lock,timeover is {$timeout} seconds");

            // 取锁
            $id = $processRedisLock->lock();
            // 如果到了超时时间还未取到会返回false，则直接抛异常
            if($id === false){
                throw new Exception('get Lock err');
            }
            

           // $this->echoAndSaveInfo($queryName, "get Lock success Id is：".$id);

            // 模拟耗时操作
            sleep($handlerTime);

            // 释放锁
            $processRedisLock->unlock($id);
           // $this->echoAndSaveInfo($queryName, "lockOut lock");
        } catch (Exception $e) {
            //$this->echoAndSaveInfo($queryName, $e->getMessage());
            // do something
        }
    }

    // 输出并且记录日志
    public function echoAndSaveInfo($queryName, $content)
    {
        $info = date('Y-m-d H:i:s') . " [{$queryName}]: {$content}" . PHP_EOL;
        echo $info;
        file_put_contents('test.txt', $info . PHP_EOL, FILE_APPEND);
    }
}

    //1.分别用一个chrome和一个ie，模拟并发请求:
        //1)http://xxx/test?queryName=task1&handlerTime=10&lockName=myLocktest&timeout=10
       // 2)http://xxx/test?queryName=task2&handlerTime=10&lockName=myLocktest&timeout=5


$a = new test();

$a->requestTask('mytest',0.1,'locks',5);//锁名，模拟中间业务时间，