Zookeeper Python应用

所谓保持独占，就是所有试图来获取这个锁的客户端，最终只有一个可以成功获得这把锁。通常的做法是把zk上的一个znode看作是一把锁，通过create znode的方式来实现。所有客户端都去创建 /distribute_lock 节点，最终成功创建的那个客户端也即拥有了这把锁。

#!/usr/bin/env python2.7# -*- coding: utf8 -*-"""File: zklock.pyBrief: 分布式锁Author:Date:"""import logging, os, timefrom kazoo.client import KazooClientfrom kazoo.recipe.lock import Lockclass ZKDistributedLock():    def __init__(self, hosts, name, logger=None, timeout=1):        """        :param hosts: zookeeper主机地址        :param name: 分布式锁名称        :param logger: 日志对象        :param timeout: 连接超时        """        self._client = None        self._lock = None        # 创建客户端对象并初始化连接        try:            self._client = KazooClient(hosts=hosts, logger=logger, timeout=timeout)            self._client.start(timeout=timeout)        except Exception, e:            logging.error('Create KazooClient Failed! Exception:{}'.format(e))        # 创建Lock对象        try:            lock_path = os.path.join("/", "locks", name)            self._lock = Lock(self._client, lock_path)        except Exception, e:            logging.error('Create Lock Failed! Exception: %s'.format(e))    def __enter__(self):        """        上下文管理器        :return:        """        if not self.acquire():            raise Exception('Get Lock Failed')        return self    def __exit__(self, exc_type, exc_val, exc_tb):        """        上下文管理器        :param exc_type:        :param exc_val:        :param exc_tb:        :return:        """        self.release()    def __del__(self):        """        :return:        """        self.release()        if self._client:            self._client.stop()            self._client = None    def acquire(self, blocking=True, timeout=None):        """        获取锁        :param blocking:        :param timeout:        :return:        """        if self._lock is None:            return False        try:            return self._lock.acquire(blocking=blocking, timeout=timeout)        except Exception, e:            logging.error('Acquire lock failed! Exception: %s'.format(e))            return False    def release(self):        """        释放锁        :return:        """        if self._lock is not None:            self._lock.release()            logging.info('Release Lock')def main():    logger = logging.getLogger()    logger.setLevel(logging.INFO)    sh = logging.StreamHandler()    formatter = logging.Formatter('%(asctime)s -%(module)s:%(filename)s-L%(lineno)d-%(levelname)s: %(message)s')    sh.setFormatter(formatter)    logger.addHandler(sh)    hosts = "172.15.227.217:2181"    name = "test"    lock = ZKDistributedLock(hosts, name, logger=logger)    with lock:        logging.info('Get lock ok,  sleep 10s')        for i in range(1, 11):            time.sleep(1)            print str(i)    logging.info('Release lock')    lock.release()if __name__ == "__main__":    main()

http://blog.csdn.net/fragmentalice/article/details/78751664