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#!/usr/bin/env python
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
"""
An example demonstrating how to send and receive UDP broadcast messages.
Every second, this application will send out a PING message with a unique ID.
It will respond to all PING messages with a PONG (including ones sent by
itself). You can tell how many copies of this script are running on the local
network by the number of "RECV PONG".
Run using twistd:
$ twistd -ny udpbroadcast.py
"""
from uuid import uuid4
from twisted.application import internet, service
from twisted.internet.protocol import DatagramProtocol
from twisted.python import log
class PingPongProtocol(DatagramProtocol):
noisy = False
def __init__(self, controller, port):
self.port = port
def startProtocol(self):
self.transport.setBroadcastAllowed(True)
def sendPing(self):
pingMsg = f"PING {uuid4().hex}"
pingMsg = pingMsg.encode("ascii")
self.transport.write(pingMsg, ("<broadcast>", self.port))
log.msg(b"SEND " + pingMsg)
def datagramReceived(self, datagram, addr):
if datagram[:4] == b"PING":
uuid = datagram[5:]
pongMsg = f"PONG {uuid}"
pongMsg = pongMsg.encode("ascii")
self.transport.write(pongMsg, ("<broadcast>", self.port))
log.msg(b"RECV " + datagram)
elif datagram[:4] == b"PONG":
log.msg(b"RECV " + datagram)
class Broadcaster:
def ping(self, proto):
proto.sendPing()
def makeService(self):
application = service.Application("Broadcaster")
root = service.MultiService()
root.setServiceParent(application)
proto = PingPongProtocol(controller=self, port=8555)
root.addService(internet.UDPServer(8555, proto))
root.addService(internet.TimerService(1, self.ping, proto))
return application
application = Broadcaster().makeService()
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