direct直连交换机实现订阅消息的子集

参考链接 

英文：  https://www.rabbitmq.com/tutorials/tutorial-four-python.html

中文： https://rabbitmq.mr-ping.com/tutorials_with_python/[4]Routing.html

提交日志 sendlog.py

#!/usr/bin/env python
# -*- coding: UTF-8 -*-
import pika
import sys

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

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

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()

订阅日志

#!/usr/bin/env python
import pika
import sys

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

发布日志

python sendlog.py error  "helllo223"

python sendlog.py info "hellloinfowarn"

python sendlog.py  warn "hellloinfowarn"

订阅日志

worker1  python sub.py  info  warn

worker2   python sub.py error warn

备注： 两个worker 的队列都绑定了 warn 绑定键   多个队列使用相同的绑定键是合法的

It is perfectly legal to bind multiple queues with the same binding key

效果：  发布的 info 信息 只有 worker1 能收到  

              发布的 error信息只有worker2 能收到

            发布的 warn信息 worker1 worker2 都能收到