redis过期事件回调函数，与有序集合

https://cloud.tencent.com/developer/article/1347437 　　python中的Redis键空间通知（过期回调）

set notify-keyspace-events KEA  【KEA参照以下字符进行设置】
此有缺点：最大的缺点是Pub / Sub实现要求发布者和订阅者一直处于启动状态。订阅服务器在停止或连接丢失时会丢失数据。
　　【意思:就是如果服务端在意外情况下出现重启或断开，需要重新设置（windows）】

import time
from redis import StrictRedisredis = StrictRedis(host='localhost', port=6379)pubsub = redis.pubsub()def event_handler(msg):
    print(msg)
    data = msg['channel'].decode().split(':')[1]
    print('***',data, redis.get(data))pubsub.psubscribe(**{'__keyspace@0__:*': event_handler})print('Starting message loop')
while True:
    message = pubsub.get_message()
    if message:
        print(message)
    else:
        time.sleep(0.01)

—订阅端

import time
from redis import StrictRedisredis = StrictRedis(host='localhost', port=6379)pubsub = redis.pubsub()
pubsub.psubscribe('__keyspace@0__:*')print('Starting message loop')
while True:
    message = pubsub.get_message()
    if message:
        print(message)
    else:
        time.sleep(0.01)

–订阅端若不添加回调事件

# python 3.7
import redis
pool = redis.ConnectionPool(host='localhost', port=6379)
r = redis.Redis(connection_pool=pool)
r.execute_command('config set notify-keyspace-events KEA') # 发布端，判断如果是第一次就执行
r.setex('a2',2,'a1')

–发布端

import redis,json,time
r = redis.ConnectionPool(host='127.0.0.1',port=6379)
rw = redis.Redis(connection_pool=r)
for i in range(1,10):
    rw.zadd('cookie_pool',json.dumps({'a1':1,'a2':2}),int(time.time()))
    time.sleep(1)
    print('设置　１个')def alive(time_space=10 * 3):
    '''
    :param time: 每隔10分钟检测一下
    :return:
    '''
    # 对应 _self.rw.zadd('cookie_pool', json.dumps(d), int(time.time()))
    while True:
        # 拿到前面的1个,并loads
        _ = rw.zrange('cookie_pool', 0, 0)[0]        # 拿到分值
        score = rw.zscore('cookie_pool', _)        print(score,time.time()-score)
        # 如果分值大于10分钟，就开始进行验证cook保活
        if time.time() - score >= time_space:
            # 进行删除
            rw.zrem('cookie_pool', _)            # 转义第一个集合的值
            first_set = json.loads(_.decode())            # 此处调用cook保活验证，，返回 bool,,假设为True
            cook_alive = True
            if cook_alive:
                print('正在设置',first_set)
                rw.zadd('cookie_pool', json.dumps(first_set), int(time.time()))
            else:
                print('已自动删除')
            # 什么都不做，自动扔掉
        else:
            print('检测时间未到')
        time.sleep(1)
alive()

—-有序集合－－－用分值判断间隔时间用作不间段保活