Python编程：redis缓存数据库

2021-11-03 08:36:24

broker缓存：

- mongodb 存硬盘

- redis 默认存内存，配置可存硬盘

- memcache 只能存内存

redis介绍

REmote DIctionary Server(Redis)

redis官网：https://redis.io/

redis数据类型：

- String 操作 set get

- Hash 操作 hset hget

- List 操作 lpush lrange

- Set 操作 sadd smembers

- Sort Set 操作

安装

windows安装下载：

https://github.com/MicrosoftArchive/redis/releases

启动服务：

切换目录到 C:\redis 运行 redis-server.exe redis.windows.conf

连接服务：

切换到redis目录下运行 redis-cli.exe -h 127.0.0.1 -p 6379

设置键值对 set myKey abc

取出键值对 get myKey

安装第三方库

pip install redis

简单连接


import redis

r = redis.Redis(host="127.0.0.1", port=6379)
r.set("foo", "xxx")
print(r.get("foo"))  # b'xxx'

url链接

redis://username[:password]@host:port/db    # TCP连接

连接池


import redis

pool = redis.ConnectionPool(host="127.0.0.1", port=6379)
r = redis.Redis(connection_pool=pool)
r.set("cat", "Tom")
print(r.get("cat"))

管道


import redis

pool = redis.ConnectionPool(host="127.0.0.1", port=6379)
r = redis.Redis(connection_pool=pool)
pipe=r.pipeline(transaction=True)

pipe.set("key1", "value1")
pipe.set("key2", "value2")

pipe.execute()  # 一起执行

print(r.get("key1"))

发布者和订阅者

# 封装的公共类

import redis


class RedisHelper:

    def __init__(self):
        self.__conn = redis.Redis(host='127.0.0.1')
        self.chan_sub = 'fm104.5'
        self.chan_pub = 'fm104.5'

    def public(self, msg):
        self.__conn.publish(self.chan_pub, msg)
        return True

    def subscribe(self):
        pub = self.__conn.pubsub()
        pub.subscribe(self.chan_sub)
        pub.parse_response()
        return pub


# 发布者

import redis_helper

obj = redis_helper.RedisHelper()
obj.public('hello')
print("发布成功")


# 订阅者

import redis_helper

obj = redis_helper.RedisHelper()
redis_sub = obj.subscribe()
print("开始订阅")

while True:
    msg = redis_sub.parse_response()
    print(msg)