RabbitMQ--Publish/Subscribe（五）

所谓覅破解

　　上篇文章中，我们实现了不同consumer接收不同级别的日志，这篇文章中，不以日志级别，使用不同日志来源。比如kernel.*、*.critical。
　　这就要使用topic exchange完成了。将message发送给topic exchange不能包含任意的routing_key了，必须是以'.'分割的多个words。words可以是任何字符。
　　用到正则如下：

• * 代替一个word
  
• # 代替0个或1个words
  

　　sender_topic.py



#!/usr/bin/env python
import pika
import sys
connection = pika.BlockingConnection(pika.ConnectionParameters(
host='localhost'))
channel = connection.channel()
channel.exchange_declare(exchange='topic_logs',
type='topic')
routing_key = sys.argv[1] if len(sys.argv) > 2 else 'anonymous.info'
message = ' '.join(sys.argv[2:]) or 'Hello World!'
channel.basic_publish(exchange='topic_logs',
routing_key=routing_key,
body=message)
print(" [x] Sent %r:%r" % (routing_key, message))
connection.close()
　　recv_topic.py



#!/usr/bin/env python
import pika
import sys
connection = pika.BlockingConnection(pika.ConnectionParameters(
host='localhost'))
channel = connection.channel()
channel.exchange_declare(exchange='topic_logs',
type='topic')
result = channel.queue_declare(exclusive=True)
queue_name = result.method.queue
binding_keys = sys.argv[1:]
if not binding_keys:
sys.stderr.write("Usage: %s [binding_key]...\n" % sys.argv[0])
sys.exit(1)
for binding_key in binding_keys:
channel.queue_bind(exchange='topic_logs',
queue=queue_name,
routing_key=binding_key)
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(callback,
queue=queue_name,
no_ack=True)
channel.start_consuming()