#!/usr/bin/env python
"""
 topic_publisher.py

 This is a simple AMQP publisher application that uses a 
 Topic exchange. The publisher specifies the routing key
 and the exchange for each message.
"""

import qpid
from qpid.client import Client
from qpid.content import Content
from qpid.queue import Empty

#----- 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.session_open()

#----- Publish some messages ------------------------------

# Create some messages and put them on the broker. Use the
# topic exchange.  The routing keys are "usa.news", "usa.weather", 
# "europe.news", and "europe.weather".


# usa.news

for i in range(5):
  message = Content("message " + str(i))
  message["routing_key"] = "usa.news"
  session.message_transfer(destination="amq.topic", content=message)

# usa.weather

for i in range(5):
  message = Content("message " + str(i))
  message["routing_key"] = "usa.weather"
  session.message_transfer(destination="amq.topic", content=message)

# europe.news

for i in range(5):
  message = Content("message " + str(i))
  message["routing_key"] = "europe.news"
  session.message_transfer(destination="amq.topic", content=message)

# europe.weather

for i in range(5):
  message = Content("message " + str(i))
  message["routing_key"] = "europe.weather"
  session.message_transfer(destination="amq.topic", content=message)

# Signal termination

message = Content("That's all, folks!")
message["routing_key"] = "control"
session.message_transfer(destination="amq.topic", content=message)


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

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

session.session_close()