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Chapter 4. Examples
This chapter demonstrates the use of AMQ Python through example programs. To run them, make sure you have completed the steps in the Chapter 2, Installation chapter for your environment and you have a running and configured broker.
See the Qpid Proton Python examples for more sample programs.
4.1. Sending Messages
This client program connects to a server using CONNECTION_URL, creates a sender for target ADDRESS, sends a message containing MESSAGE_BODY, closes the connection, and exits.
Example: Sending Messages
from __future__ import print_function
import sys
from proton import Message
from proton.handlers import MessagingHandler
from proton.reactor import Container
class SendHandler(MessagingHandler):
def __init__(self, conn_url, address, message_body):
super(SendHandler, self).__init__()
self.conn_url = conn_url
self.address = address
self.message_body = message_body
def on_start(self, event):
conn = event.container.connect(self.conn_url)
event.container.create_sender(conn, self.address)
def on_link_opened(self, event):
print("SEND: Opened sender for target address '{0}'".format
(event.sender.target.address))
def on_sendable(self, event):
message = Message(self.message_body)
event.sender.send(message)
print("SEND: Sent message '{0}'".format(message.body))
event.sender.close()
event.connection.close()
def main():
try:
conn_url, address, message_body = sys.argv[1:4]
except ValueError:
sys.exit("Usage: send.py CONNECTION-URL ADDRESS MESSAGE-BODY")
handler = SendHandler(conn_url, address, message_body)
container = Container(handler)
container.run()
if __name__ == "__main__":
try:
main()
except KeyboardInterrupt:
pass
Running the Example
To run the example program, copy it to a local file and invoke it using the python command.
$ python send.py amqp://localhost queue1 hello
4.2. Receiving Messages
This client program connects to a server using CONNECTION_URL, creates a receiver for source ADDRESS, and receives messages until it is terminated or it reaches COUNT messages.
Example: Receiving Messages
from __future__ import print_function
import sys
from proton.handlers import MessagingHandler
from proton.reactor import Container
class ReceiveHandler(MessagingHandler):
def __init__(self, conn_url, address, desired):
super(ReceiveHandler, self).__init__()
self.conn_url = conn_url
self.address = address
self.desired = desired
self.received = 0
def on_start(self, event):
conn = event.container.connect(self.conn_url)
event.container.create_receiver(conn, self.address)
def on_link_opened(self, event):
print("RECEIVE: Created receiver for source address '{0}'".format
(self.address))
def on_message(self, event):
message = event.message
print("RECEIVE: Received message '{0}'".format(message.body))
self.received += 1
if self.received == self.desired:
event.receiver.close()
event.connection.close()
def main():
try:
conn_url, address = sys.argv[1:3]
except ValueError:
sys.exit("Usage: receive.py CONNECTION-URL ADDRESS [MESSAGE-COUNT]")
try:
desired = int(sys.argv[3])
except (IndexError, ValueError):
desired = 0
handler = ReceiveHandler(conn_url, address, desired)
container = Container(handler)
container.run()
if __name__ == "__main__":
try:
main()
except KeyboardInterrupt:
pass
Running the Example
To run the example program, copy it to a local file and invoke it using the python command.
$ python receive.py amqp://localhost queue1