RabbitMQ之Routing(路由有选择的接收)

创建绑定方式　　

channel.queue_bind(exchange="交换器的名字",
                  queue="队列的名字")

绑定使用路由参数(主要避免basic_publish参数混淆)

channel.queue_bind(exchange="交换器的名字",
                    queue="队列的名字",
                    routing_key="black")

直接交换

　　在消息发布与订阅中，消息广播给所有在线的消费者，假如说有时候我们只需要接收严重错误的日志报告写到磁盘中，之前使用的fanout交换，并没有带来太大的灵活性

　　此时就可以使用直接交换：思想绑定密钥与路由密钥完全匹配的队列才能发收消息

 多重绑定

　　用相同的绑定密钥绑定多个队列

但在这里官方是将每种严重性创建一个新的绑定关系

 send_log_direct.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-

import pika
import sys

credentials = pika.PlainCredentials('admin', 'admin123456')
connection = pika.BlockingConnection(pika.ConnectionParameters(host='192.168.1.6', credentials=credentials))
channel = connection.channel()
# 申明交换器名以及类型
channel.exchange_declare(exchange='direct_logs', exchange_type='direct')
# 日志严重级别
severity = sys.argv[1] if len(sys.argv) > 1 else 'info'
message = ' '.join(sys.argv[2:]) or 'Hello World!'
channel.basic_publish(
    exchange='direct_logs', routing_key=severity, body=message)
print(" [x] Sent %r:%r" % (severity, message))
connection.close()

receive_log_direct.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-

import pika
import sys

credentials = pika.PlainCredentials('admin', 'admin123456')
connection = pika.BlockingConnection(pika.ConnectionParameters(host='192.168.1.6', credentials=credentials))
channel = connection.channel()

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

result = channel.queue_declare(queue='', exclusive=True)
queue_name = result.method.queue

severities = sys.argv[1:]
if not severities:
    sys.stderr.write("Usage: %s [info] [warning] [error]
" % sys.argv[0])
    sys.exit(1)

for severity in severities:
    channel.queue_bind(
        exchange='direct_logs', queue=queue_name, routing_key=severity)

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


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


channel.basic_consume(
    queue=queue_name, on_message_callback=callback, auto_ack=True)

channel.start_consuming()