rabbitMQ direct实现广播

原理图：

消息广播者：

'''

exchange 类型：
fanout：所有bind到此exchange 的queue 都可以接收到消息

direct： 通过routingkey和exchange 决定的那个唯一的queue 可以接收到消息
    接收端可以接收指定级别的消息:info , warning , error

topic: 所有符合routingkey的routingkey所bind的queue 可以接收消息

表达式符合说明：
    #代表一个或多个字符
    *代表任何字符


header：通过headers来决定把消息发给哪些queue
'''

import  pika

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

channel = connection.channel()

channel.exchange_declare(exchange='direct_logs',exchange_type='direct')

msg = "using direct .."
#消息级别
severity = 'info'
channel.basic_publish(exchange='direct_logs',routing_key=severity,body=msg)

print('send %s:%s'%(severity,msg))

channel.close()

消息接收者：

import pika
import sys

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

channel.exchange_declare(exchange='direct_logs',exchange_type='direct')


result = channel.queue_declare(exclusive=True)

queueName = result.method.queue

severities = 'info'

channel.queue_bind(exchange='direct_logs',queue=queueName,routing_key=severities)

def callback(ch , method ,properties, body):
    print("接收：",body)
    print("routingKey：", method.routing_key)
channel.basic_consume(callback,queue=queueName,no_ack=True)

channel.start_consuming()
channel.close()