客戶端通過發送命令來調用服務端的某些服務，服務端把結果再返回給客戶端

這樣使得RabbitMQ的消息發送端和接收端都能發送消息

返回結果的時候需要指定另一個隊列

服務器端

# -*- coding:utf-8 -*-
__author__ = "MuT6 Sch01aR"

import pika
import os

connection = pika.BlockingConnection(pika.ConnectionParameters(host=‘127.0.0.1‘))
channel = connection.channel()

channel.queue_declare(queue=‘rpc_q‘)


def cmd(n):
    cmd_result = os.popen(n)
    cmd_result = cmd_result.read()
    return cmd_result


def on_request(ch, method, props, body):
    body = body.decode()
    print(‘執行命令：‘, body)
    response = cmd(body)
    print(response)

    ch.basic_publish(exchange=‘‘,
                     routing_key=props.reply_to,  # 把消息發送到用來返回消息的queue
                     properties=pika.BasicProperties(correlation_id=props.correlation_id),
                     body=str(response),
                     )
    ch.basic_ack(delivery_tag=method.delivery_tag)

channel.basic_qos(prefetch_count=1)

channel.basic_consume(on_request, queue=‘rpc_q‘)

print(‘等待請求‘)
channel.start_consuming()

客戶端

# -*- coding:utf-8 -*-
__author__ = "MuT6 Sch01aR"

import pika
import uuid
import time


class RpcClient(object):
    def __init__(self):
        self.connection = pika.BlockingConnection(pika.ConnectionParameters(host=‘127.0.0.1‘))

        self.channel = self.connection.channel()

        result = self.channel.queue_declare(exclusive=True)
        self.callback_queue = result.method.queue  # 生成隨機的queue

        self.channel.basic_consume(self.on_response,  # 一收到消息就調用op_response方法
                                   no_ack=True,
                                   queue=self.callback_queue,
                                   )

    def on_response(self, ch, method, props, body):
        if self.corr_id == props.correlation_id:  # 判斷服務端發送的uuid和客戶端發送的uuid是否匹配
            self.response = body

    def call(self, n):
        self.response = None
        self.corr_id = str(uuid.uuid4())
        self.channel.basic_publish(exchange=‘‘,
                                   routing_key=‘rpc_q‘,
                                   properties=pika.BasicProperties(
                                       reply_to=self.callback_queue,  # 把返回的消息發送到用來返回結果的queue
                                       correlation_id=self.corr_id,
                                   ),
                                   body=n,
                                   )
        while self.response is None:
            self.connection.process_data_events()  # 相當於非阻塞的start_consuming()
            print(‘當前沒有消息‘)
            time.sleep(3)
        return self.response

while True:
    cmd = input(‘>>>:‘).strip()
    print(‘執行命令：‘, cmd)
    rpc = RpcClient()
    response = rpc.call(cmd)
    print(response.decode())

開啟一個客戶端和一個服務端

執行結果：

服務器端

客戶端

Python-RabbitMQ消息隊列實現rpc