redis分布式锁- 面试宝典

pythonCopy codeimport redis
import time
def acquire_lock(conn, lock_name, acquire_timeout=10, lock_timeout=10):
    identifier = str(uuid.uuid4())  # 生成一个唯一的标识符作为锁的值
    end_time = time.time() + acquire_timeout
    while time.time() < end_time:
        if conn.setnx(lock_name, identifier):
            conn.expire(lock_name, lock_timeout)
            return identifier
        time.sleep(0.001)
    return None
def release_lock(conn, lock_name, identifier):
    with conn.pipeline() as pipe:
        while True:
            try:
                # 监视锁，确保在操作过程中锁没有被其他进程修改
                pipe.watch(lock_name)
                if conn.get(lock_name) == identifier:
                    # 释放锁
                    pipe.multi()
                    pipe.delete(lock_name)
                    pipe.execute()
                    return True
                pipe.unwatch()
                break
            except redis.exceptions.WatchError:
                pass
    return False
# 连接Redis
conn = redis.Redis(host='localhost', port=6379, db=0)
# 获取锁
lock_name = 'mylock'
identifier = acquire_lock(conn, lock_name)
if identifier:
    try:
        # 执行需要保护的代码逻辑
        print("获取到锁，执行代码逻辑...")
        time.sleep(5)
    finally:
        # 释放锁
        release_lock(conn, lock_name, identifier)
        print("释放锁")
else:
    print("获取锁超时，无法执行代码逻辑")