safe_redis_lock 0.1

a safe redis lock in Single node Redis

项目描述

• 一个单机版的redis分布式锁( A single redis distributed lock)

• 项目使用set命令来加锁

• 使用lua脚本来释放锁以保证原子性

• 注意事项,传入的redis连接池需要必须参数一样,同一个redis数据库

• 当block=False的时候如果没有获得锁则返回一个AcquireFailException异常

• acquire方法返回True时候则说明获得锁成功

使用方法一

• 装饰器使用方法

• 新建一个RedisLock对象.使用RedisLock的lock装饰器来装饰需要保证原子性的函数

• 注意该函数不能是阻塞的

• import threading
  import redis
  
  from safe_redis_lock import RedisLock
  pool = redis.ConnectionPool(host='127.0.0.1', port=6379, password='lyc', db=0)
  
  conn = redis.Redis(connection_pool=pool)
  
  conn.set('producer', 10000)
  redis_lock_ = RedisLock(lock_timeout=5, pool=pool, block=True)
  
  
  @redis_lock_.lock
  def consumer_pp(conn):
      num = int(conn.get('producer'))
      if num == 0:
          return True
      else:
          print(f'we consumer one left --> {num}')
          conn.set('producer', num - 1)
  
  
  def consumer():
      pool = redis.ConnectionPool(host='127.0.0.1', port=6379, password='lyc', db=0)
      while True:
          conn = redis.Redis(connection_pool=pool)
          if consumer_pp(conn):
              break
  
  
  def consumer_thread():
      from threading import Thread
      for i in range(20):
          Thread(target=consumer).start()
  
  
  consumer_thread()

使用方法二:

from safe_redis_lock import RedisLock,AcquireFailException

import redis
import threading
import os
pool = redis.ConnectionPool(host='127.0.0.1', port=6379, password='lyc', db=0)

conn = redis.Redis(connection_pool=pool)

conn.set('producer', 10000)
redis_lock_ = RedisLock(lock_timeout=5, pool=pool, block=True)


def consumer_pp(conn):
    num = int(conn.get('producer'))
    if num == 0:
        return True
    else:
        print(f'we consumer one left --> {num}')
        conn.set('producer', num - 1)


def consumer():
    pool = redis.ConnectionPool(host='127.0.0.1', port=6379, password='lyc', db=0)
    while True:
        conn = redis.Redis(connection_pool=pool)
        value = f'{threading.current_thread().ident}-{os.getpid()}'
        get_lock = False
        try:
            get_lock = redis_lock_.acquire(value = value)
            if get_lock:
                if consumer_pp(conn):
                    break
        except AcquireFailException:
            print('can not get the lock')
        finally:
            if get_lock:
                redis_lock_.release(value)


def consumer_thread():
    from threading import Thread
    for i in range(20):
        Thread(target=consumer).start()


consumer_thread()