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我需要在交换机上设置多个队列。我想创建一个连接，然后声明多个队列（这可行），然后在多个队列上发布消息（这不起作用）。

我设置了一些测试代码来执行此操作，但它每次都在第二次发布时挂断。我认为它不喜欢在不关闭连接的情况下在多个队列上发布，因为当我在单个队列上发布（甚至单个队列上的多条消息）时，此代码有效。

我需要添加一些东西来完成这项工作吗？我真的很想不必关闭发布之间的连接。此外，当我让我的消费者启动时，当我在多个队列上发送到 basic_publish() 时，他们看不到任何东西。当我在单个队列上发布时，我确实看到消息几乎立即出现。

#!/usr/bin/env python
import pika


queue_names = ['1a', '2b', '3c', '4d']


# Variables to hold our connection and channel
connection = None
channel = None


# Called when our connection to RabbitMQ is closed
def on_closed(frame):
    global connection
    # connection.ioloop is blocking, this will stop and exit the app
    connection.ioloop.stop()



def on_connected(connection):
    """
    Called when we have connected to RabbitMQ
    This creates a channel on the connection
    """
    global channel #TODO: Test removing this global call

    connection.add_on_close_callback(on_closed)

    # Create a channel on our connection passing the on_channel_open callback
    connection.channel(on_channel_open)



def on_channel_open(channel_):
    """
    Called when channel opened
    Declare a queue on the channel
    """
    global channel

    # Our usable channel has been passed to us, assign it for future use
    channel = channel_


    # Declare a set of queues on this channel
    for queue_name in reversed(queue_names):
        channel.queue_declare(queue=queue_name, durable=True,
                              exclusive=False, auto_delete=False,
                              callback=on_queue_declared)
        #print "done making hash"

def on_queue_declared(frame):
    """
    Called when a queue is declared
    """
    global channel

    print "Sending 'Hello World!' on ", frame.method.queue

    # Send a message
    channel.basic_publish(exchange='',
                          routing_key=frame.method.queue,
                          body='Hello World!')


# Create our connection parameters and connect to RabbitMQ
connection = pika.SelectConnection(pika.ConnectionParameters('localhost'), \
                                   on_connected)

# Start our IO/Event loop
try:
    connection.ioloop.start()
except KeyboardInterrupt:
    print "interrupt"
    # Gracefully close the connection
    connection.close()
    # Loop until we're fully closed, will stop on its own
    #connection.ioloop.start()
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1 回答 1

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我对此的解决方案是使用一个变量来跟踪我的所有队列是否都已声明。

在 on_queue_declared() 中，我会检查这个变量，如果我的所有队列都被声明，那么我开始发布消息。我相信在取回所有 Queue.DeclareOks 之前尝试发布消息会导致问题。

于 2012-06-29T19:51:57.987 回答