python redis 发布订阅 实现 RPC同步

工作中用到的场景是，python主程序发布消息到Redis，然后停住等待Redis上订阅的Response。等待过程是阻塞的，相当于把异步通信封装成同步通信，类似于Java的RPC。

RPC封装的代码如下：

import redis
import uuid

class RpcClient(object):
    def __init__(self, sub_channel):
        self.redis = redis.StrictRedis(host='localhost', port='6379')
        self.response = None
        self.channel = sub_channel
        self.ps = self.redis.pubsub()
        self.ps.subscribe(sub_channel)
        self.msg = self.ps.parse_response()
        print('开始接收----')

    def on_response(self, message):
        data = json.loads(message)
        if data['Result']['Uuid'] == self.uuid:
            self.response = data['Result']

    def call(self, ch ,n):
        dict1 = {'Uuid': str(uuid.uuid4())}
        n.update(dict1)
        self.uuid = n['Uuid']
        print('uuid is ', self.uuid)
        request = json.dumps(n)
        self.redis.publish(ch, request)
        while self.response is None:
            print('waiting...')
            self.on_response(self.ps.parse_response()[2])
        return self.response

 

主程序调用方法：

# 业务逻辑...

rpc = RpcClient('responseChannel')

response = rpc.call('requestChannel', request_body)