RC9/qpid/python/examples/fanout/listener.py

#!/usr/bin/env python
#
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# to you under the Apache License, Version 2.0 (the
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# 
#   http://www.apache.org/licenses/LICENSE-2.0
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"""
 listener.py

 This AMQP client reads messages from a message
 queue named "message_queue".
"""

import qpid
import sys
import os
from qpid.util import connect
from qpid.connection import Connection
from qpid.datatypes import Message, RangedSet, uuid4
from qpid.queue import Empty

# 

from time         import sleep

#----- Message Receive Handler -----------------------------
class Receiver:
  def __init__ (self):
    self.finalReceived = False

  def isFinal (self):
    return self.finalReceived
    
  def Handler (self, message):
    content = message.body
    session.message_accept(RangedSet(message.id))
    print content
    if content == "That's all, folks!":
      self.finalReceived = True


#----- Initialization --------------------------------------

#  Set parameters for login

host="127.0.0.1"
port=5672
user="guest"
password="guest"

# If an alternate host or port has been specified, use that instead
# (this is used in our unit tests)
if len(sys.argv) > 1 :
  host=sys.argv[1]
if len(sys.argv) > 2 :
  port=int(sys.argv[2])

#  Create a connection.
socket = connect(host, port)
connection = Connection (sock=socket, username=user, password=password)
connection.start()
session = connection.session(str(uuid4()))

#----- Read from queue --------------------------------------------

# Create a server-side queue and route messages to it.
# The server-side queue must have a unique name. Use the
# session id for that.

server_queue_name = session.name
session.queue_declare(queue=server_queue_name)
session.exchange_bind(queue=server_queue_name, exchange="amq.fanout")

# Create a local queue to receive messages from the server-side
# queue.
local_queue_name = "local_queue"
local_queue = session.incoming(local_queue_name)


# The local queue name identifies the client-side queue.

local_queue_name = "local_queue"
local_queue = session.incoming(local_queue_name)

# Call message_subscribe() to tell the broker to deliver messages
# from the AMQP queue to this local client queue. The broker will
# start delivering messages as soon as local_queue.start() is called.

session.message_subscribe(queue=server_queue_name, destination=local_queue_name)
local_queue.start()

receiver = Receiver ()
local_queue.listen (receiver.Handler)

while not receiver.isFinal ():
  sleep (1)


#----- Cleanup ------------------------------------------------

# Clean up before exiting so there are no open threads.
#

session.close()