Chapter 4. Examples
This chapter demonstrates the use of AMQ Python through example programs.
For more examples, see the AMQ Python example suite and the Qpid Proton Python examples.
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)
# To connect with a user and password:
# conn = event.container.connect(self.conn_url, user="<user>", password="<password>")
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. For more information, see Chapter 3, Getting started.
$ 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)
# To connect with a user and password:
# conn = event.container.connect(self.conn_url, user="<user>", password="<password>")
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. For more information, see Chapter 3, Getting started.
$ python receive.py amqp://localhost queue1
