Pyhton浅谈-Python与中间件之Redis
Posted catt1e
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Pyhton浅谈-Python与中间件之Redis相关的知识,希望对你有一定的参考价值。
Pyhton浅谈-Python与中间件之Redis(5)
一、Redis也可以作为缓存中间件使用:
Redis是典型的NoSQL的代表,也可以使用Python操作Redis,在此不做过多介绍,见博客:https://www.cnblogs.com/catt1e/p/12565345.html,此博客主要介绍Redis作为缓存中间件;
二、Redis与Memcache的比较:
三、Python处理Redis:
此代码与上篇文章Memcache大同小异,但是Redis支持可以从不同的数据库中存取数据(代码中表现为db_type),代码主要功能与上篇文章Python对于pymemcache的处理大同小异,在此不做赘述,直接看代码:、
#!/usr/bin/env python # -*- coding:utf-8 -*- # Author:catt1e import time import json import redis def get_data(db_type=\'tv\'): \'\'\'获取数据 1. 从mysql获取 2. 从其他接口获取 \'\'\' data = None if db_type == \'tv\': data = {\'ch\':[\'ch001\',\'ch002\'], \'mudan\':[\'牡丹A\',\'牡丹B\']} elif db_type == \'pc\': data = {\'lenovo\':[\'le-001\',\'le-002\'], \'dell\':[\'dell-1\',\'dell-2\']} time.sleep(3) return data def show_data(data): for k, v in data.items(): print(k, v) def mid_cache(k, data, db_type="tv"): \'\'\'缓存数据 \'\'\' try: client = None if db_type == \'tv\': client = redis.StrictRedis(host=\'localhost\', port=6379, db=0) elif db_type == \'pc\': client = redis.StrictRedis(host=\'localhost\', port=6379, db=1) ret = client.set(k, json.dumps(data)) return ret except Exception as e: print(e) return False redis_type = { "tv": 0, "pc": 1 } def get_cache(k, db_type="tv"): \'\'\'从k取缓存数据\'\'\' client = redis.StrictRedis(host=\'localhost\', port=6379, db=redis_type[db_type]) try: data = client.get(k) return json.loads(data) except Exception as e: print(e) return False def main(): k = \'tv\' data = get_cache(k, db_type="pc") if data: print(\'from cache...\') show_data(data) else: print(\'no data, 第一次取\') data = get_data(db_type="pc") mid_cache(k, data, db_type="pc") if __name__ == \'__main__\': main()
四、Redis订阅和发布功能:
1.订阅和发布功能:
2.Pyhton操作Redis订阅和发布功能:
代码主要功能介绍:此代码分为redis_pub.py(发布端)和redis_sub.py(订阅端)两个,发布端可以在频道channels上发布信息,订阅端会监听发布端的消息,随后并输出所监听到的消息:
#!/usr/bin/env python # -*- coding:utf-8 -*- # Author:catt1e # redis_pub.py 发布端 import redis client = redis.Redis() channels = ["Jay", "SHE", \'Beyond\'] def main(): print("可以发布到任意一个频道:") for i in channels: print(i) while True: ch = input("输入频道:") print("输入发送的信息(q:退出):") msg = input(\'>>\') if msg == \'q\': break client.publish(ch, msg) if __name__ == \'__main__\': main() #!/usr/bin/env python # -*- coding:utf-8 -*- # Author:catt1e # redis_sub.py订阅端 import redis client = redis.StrictRedis() channels = ["Jay", "SHE", \'Beyond\'] # 得到pubsub对象 # 通过对象订阅频道 # listen监听频道 def subscribe(): s1 = client.pubsub() s1.subscribe(channels) s2 = client.pubsub() s2.subscribe(\'SHE\') s3 = client.pubsub() s3.subscribe(channels[:2]) show_msg(s1, \'s1\') show_msg(s2, \'s2\') show_msg(s3, \'s3\') def show_msg(sub_obj, sub_name): for msg in sub_obj.listen(): if msg["type"] == "message": print(f\'{sub_name} get {msg["data"].decode()} from {msg["channel"]}\') def main(): subscribe() if __name__ == \'__main__\': main()
以上是关于Pyhton浅谈-Python与中间件之Redis的主要内容,如果未能解决你的问题,请参考以下文章