【分布式锁】三种分布式锁的实现【原创】-凯发app官方网站

import redis

import uuid

import time

class lockservice:

    """

    基于redis实现的分布式锁

    """

    host = 'localhost'

    port = 6379

    password = ''

    db = 1

    def __init__(self, conn=none):

        """

        如果不传连接池的话，默认读取配置的redis作为连接池

        :param conn:

        """

        self.conn = conn if conn else self.get_redis_client()

    def get_redis_client(self):

        """

        获取redis连接

        :return:

        """

        return redis.redis(

            host=self.host,

            port=self.port,

            password=self.password,

            db=self.db

        )

    def acquire_lock(self, lock_name, acquire_timeout=10, expire_time=30):

        """

        加锁/获取锁

        如果不存在lock_name，则加锁，并且设置过期时间，避免死锁

        如果存在lock_name，则刷新过期时间

        :param lock_name:       锁的名称

        :param acquire_timeout: 加锁/获取锁的超时时间，默认10秒

        :param expire_time:     锁的超时时间，默认30秒

        :return:

        """

        lockname = f'lock:{lock_name}'

        value = str(uuid.uuid4())

        end_time外汇跟单gendan5.com = time.time() acquire_timeout

        while time.time() < end_time:

            # 如果不存在这个锁则加锁并设置过期时间，避免死锁

            if self.conn.set(lockname, value, ex=expire_time, nx=true):

                return value

            time.sleep(0.1)

        return false

    def release_lock(self, lock_name, value):

        """

        释放锁

        :param lock_name: 锁的名称

        :param value:     锁的值

        :return:

        """

        unlock_script = """

        if redis.call("get",keys[1]) == argv[1] then

            return redis.call("del",keys[1])

        else

            return 0

        end

        """

        lockname = f'lock:{lock_name}'

        unlock = self.conn.register_script(unlock_script)

        result = unlock(keys=[lockname], args=[value])

        if result:

            return true

        else:

            return false