python rabbitmq消息发布订阅

发送端：

import pika
import sys

connection = pika.BlockingConnection(pika.ConnectionParameters(
    host='localhost'))
channel = connection.channel()

channel.exchange_declare(exchange='logs',exchange_type='fanout')

message = ' '.join(sys.argv[1:]) or "info: Hello World!"
channel.basic_publish(exchange='logs',
                      routing_key='',
                      body=message)
print(" [x] Sent %r" % message)
connection.close()

接收端：

import pika

connection = pika.BlockingConnection(pika.ConnectionParameters(
    host='localhost'))
channel = connection.channel()

channel.exchange_declare(exchange='logs',
                         exchange_type='fanout')

result = channel.queue_declare(exclusive=True)  # 不指定queue名字,rabbit会随机分配一个名字,exclusive=True会在使用此queue的消费者断开后,自动将queue删除
queue_name = result.method.queue
print(queue_name)
channel.queue_bind(exchange='logs',
                   queue=queue_name)

print(' [*] Waiting for logs. To exit press CTRL+C')

def callback(ch, method, properties, body):
    print(" [x] %r" % body)

channel.basic_consume(callback,
                      queue=queue_name,
                      no_ack=True)

channel.start_consuming()

exchange不会保存数据，如果没客户端接受，就丢弃，也就是说，客户端会丢失启动前发送端发送的数据。