使用rabbitmq消息队列

一、前言

　　在python中本身就是存在队列queue。一个是线程队列queue，另一个是进程multiprocessing中的队列Queue。

　　线程queue：只用于线程之间的数据交互

　　进程Queue：用于同一进程下父进程和子进程之间的数据交互，或者同属于一个父进程下的多个子进程之间的交互

二、RabbitMQ

　　如果是多个进程间（不同的应用程序之间）、多个系统需要进行数据交互，那么就可以使用消息服务来解决这些问题。消息服务擅长于解决多系统、异构系统间的数据交换（消息通知/通讯）问题，你也可以把它用于系统间服务的相互调用（RPC）。RabbitMQ就是当前最主流的消息中间件之一。

　　RabbitMQ的基础介绍：点击查看

　　实现最简单的队列通信

　　

　　send端　　

# -*- coding: UTF-8 -*-
 
import pika
 
connection = pika.BlockingConnection(pika.ConnectionParameters(
    'localhost'))
 
# 声明一个管道
channel = connection.channel()
 
# 声明queue
channel.queue_declare(queue='hello')  # queue的名称
 
# n RabbitMQ a message can never be sent directly to the queue, it always needs to go through an exchange.
channel.basic_publish(exchange='',
                      routing_key='hello',
                      body='Hello World!')
print(" [x] Sent 'Hello World!'")
connection.close()

　　receive端　　

# -*- coding: UTF-8 -*-
 
import pika
 
connection = pika.BlockingConnection(pika.ConnectionParameters(
    'localhost'))
channel = connection.channel()
 
# You may ask why we declare the queue again ‒ we have already declared it in our previous code.
# We could avoid that if we were sure that the queue already exists. For example if send.py program
# was run before. But we're not yet sure which program to run first. In such cases it's a good
# practice to repeat declaring the queue in both programs.
 
# 这个queue名称就是刚才send端中声明的，再次声明就能保证找到生产者发送的数据
# 如果消费者在生产者之前先启动了，会找不到这个消息队列，就会报错
channel.queue_declare(queue='hello')
 
def callback(ch, method, properties, body):
    print('--->>', ch, '\n', method, '\n', properties)
    print(" [x] Received %r" % body)
 
# ch: 声明的管道channel对象内存地址
#
 
channel.basic_consume(callback,  # 如果收到消息就调用callback函数来处理消息
                      queue='hello',
                      no_ack=True)
 
print(' [*] Waiting for messages. To exit press CTRL+C')
 
# 永远收下去，没有就在这卡住
channel.start_consuming()

三、连接远程rabbitmq

　　连接远程rabbitmq可能会有认证问题，需要输入用户名和密码

　　windows下设置用户名、密码和权限：here

　　linux环境下设置用户名、密码和权限：here

　　基本都在最后面

　　send端的设置：　

# -*- conding:utf-8 -*-
 
import pika
 
# 认证信息
credentials = pika.PlainCredentials('bigberg', '111111')
 
connection = pika.BlockingConnection(pika.ConnectionParameters(
    '172.16.200.109', 5672, '/', credentials))
 
# 声明一个管道
channel = connection.channel()
 
# 声明queue
channel.queue_declare(queue='hello')  # queue的名称
 
# n RabbitMQ a message can never be sent directly to the queue, it always needs to go through an exchange.
channel.basic_publish(exchange='',
                      routing_key='hello',
                      body='from remote server')
print(" [x] Sent 'from remote server'")
connection.close()