Python Locker Implementation Notes ---- python 中锁的实现

分布式锁

portalocker.RedisLock

实现方式
- redis pubsub channel

创建

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import portalocker

lock = portalocker.RedisLock('some_lock_channel_name')

with lock:
print('do something here')

# *** Redis 连接设定

Redis 连接设定
- 使用 redis.client.Redis 类实现
用 RedisLock 可选关键字参数 redis_kwargs: typing.Optional[typing.Dict] = None 指定

参考

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class Redis:
    def __init__(self, host='localhost', port=6379,
             db=0, password=None, socket_timeout=None,
             socket_connect_timeout=None,
             socket_keepalive=None, socket_keepalive_options=None,
             connection_pool=None, unix_socket_path=None,
             encoding='utf-8', encoding_errors='strict',
             charset=None, errors=None,
             decode_responses=False, retry_on_timeout=False,
             ssl=False, ssl_keyfile=None, ssl_certfile=None,
             ssl_cert_reqs='required', ssl_ca_certs=None,
             ssl_check_hostname=False,
             max_connections=None, single_connection_client=False,
             health_check_interval=0, client_name=None, username=None):

python-redis-lock pip 包实现

参考：GitHub - ionelmc/python-redis-lock: Lock context manager implemented via redi…
模块：＝redis_lock＝

例子

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from redis import Redis
conn = Redis()

import redis_lock
lock = redis_lock.Lock(conn, "name-of-the-lock")
if lock.acquire(blocking=False):
    print("Got the lock.")
    lock.release()
else:
    print("Someone else has the lock.")

文件锁

fcntl 模块
portalocker 模块
filelock 模块
- 参考：filelock · PyPI

文件夹锁

例子

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class LockDirectory:
    def __init__(self, directory):
        assert os.path.exists(directory)
        self.directory = directory

    def __enter__(self):
        self.dir_fd = os.open(self.directory, os.O_RDONLY)
        try:
        # fcntl.flock(self.dir_fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
        fcntl.flock(self.dir_fd, fcntl.LOCK_EX)
        except IOError as ex:
        raise Exception('Somebody else is locking %r - quitting.' % self.directory)
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        # fcntl.flock(self.dir_fd,fcntl.LOCK_UN)
        os.close(self.dir_fd)

文章目录

分布式锁

portalocker.RedisLock

python-redis-lock pip 包实现

文件锁

文件夹锁