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+#!/usr/bin/env python
+"""
+ topic_subscriber.py
+
+ This subscriber creates private queues and binds them
+ to the topics "usa.#", "europe.#", "#.news", and "#.weather".
+"""
+
+import base64
+
+import qpid
+from qpid.client import Client
+from qpid.content import Content
+from qpid.queue import Empty
+
+#----- Functions -------------------------------------------
+
+def dump_queue(client, queue_name):
+
+ print "Messages queue: " + queue_name
+
+ consumer_tag = queue_name # Use the queue name as the consumer tag - need a unique tag
+ queue = client.queue(consumer_tag)
+
+ # Call basic_consume() to tell the broker to deliver messages
+ # from the AMQP queue to a local client queue. The broker will
+ # start delivering messages as soon as basic_consume() is called.
+
+ session.message_subscribe(queue=queue_name, destination=consumer_tag)
+ session.message_flow(consumer_tag, 0, 0xFFFFFFFF)
+ session.message_flow(consumer_tag, 1, 0xFFFFFFFF)
+
+ content = "" # Content of the last message read
+ final = "That's all, folks!" # In a message body, signals the last message
+ message = 0
+
+ while content != final:
+ try:
+ message = queue.get()
+ content = message.content.body
+ print content
+ except Empty:
+ if message != 0:
+ message.complete(cumulative=True)
+ print "No more messages!"
+ return
+
+
+ # Messages are not removed from the queue until they
+ # are acknowledged. Using multiple=True, all messages
+ # in the channel up to and including the one identified
+ # by the delivery tag are acknowledged. This is more efficient,
+ # because there are fewer network round-trips.
+
+ if message != 0:
+ message.complete(cumulative=True)
+
+
+#----- Initialization --------------------------------------
+
+# Set parameters for login
+
+host="127.0.0.1"
+port=5672
+amqp_spec="/usr/share/amqp/amqp.0-10-preview.xml"
+user="guest"
+password="guest"
+
+# Create a client and log in to it.
+
+spec = qpid.spec.load(amqp_spec)
+client = Client(host, port, spec)
+client.start({"LOGIN": user, "PASSWORD": password})
+
+session = client.session()
+session_info = session.session_open()
+session_id = session_info.session_id
+
+#----- Main Body -- ----------------------------------------
+
+
+news = "news" + base64.urlsafe_b64encode(session_id)
+weather = "weather" + base64.urlsafe_b64encode(session_id)
+usa = "usa" + base64.urlsafe_b64encode(session_id)
+europe = "europe" + base64.urlsafe_b64encode(session_id)
+
+session.queue_declare(queue=news, exclusive=True)
+session.queue_declare(queue=weather, exclusive=True)
+session.queue_declare(queue=usa, exclusive=True)
+session.queue_declare(queue=europe, exclusive=True)
+
+# Routing keys may be "usa.news", "usa.weather", "europe.news", or "europe.weather".
+
+# The '#' symbol matches one component of a multipart name, e.g. "#.news" matches
+# "europe.news" or "usa.news".
+
+session.queue_bind(exchange="amq.topic", queue=news, routing_key="#.news")
+session.queue_bind(exchange="amq.topic", queue=weather, routing_key="#.weather")
+session.queue_bind(exchange="amq.topic", queue=usa, routing_key="usa.#")
+session.queue_bind(exchange="amq.topic", queue=europe, routing_key="europe.#")
+
+# Bind each queue to the control queue so we know when to stop
+
+session.queue_bind(exchange="amq.topic", queue=news, routing_key="control")
+session.queue_bind(exchange="amq.topic", queue=weather, routing_key="control")
+session.queue_bind(exchange="amq.topic", queue=usa, routing_key="control")
+session.queue_bind(exchange="amq.topic", queue=europe, routing_key="control")
+
+# Remind the user to start the topic producer
+
+print "Queues create - please start the topic producer"
+
+# Call dump_queue to print messages from each queue
+
+dump_queue(client, news)
+dump_queue(client, weather)
+dump_queue(client, usa)
+dump_queue(client, europe)
+
+#----- Cleanup ------------------------------------------------
+
+# Clean up before exiting so there are no open threads.
+
+session.session_close()