Example or udp discovery in python

multicast_udp_discovery.py

import socket
import time
import uuid
import struct

instance_id = uuid.uuid4().hex
payload = "this is data"
multicast_group = ('224.31.5.85', 19845)

discovery = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
ttl = struct.pack('b', 1)
discovery.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, ttl)
discovery.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
discovery.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)

group = socket.inet_aton(multicast_group[0])
mreq = struct.pack('4sL', group, socket.INADDR_ANY)
discovery.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

discovery.settimeout(0.2)
discovery.bind(("", 19845))
while True:
	message = "/".join([instance_id, payload]).encode()

	# send discovery message
	discovery.sendto(message, multicast_group)
	
	# process all other received messages
	while True:
			try:
				data, addr = discovery.recvfrom(1024)				
			except socket.timeout:
				break
			else:
				rec_instance_id, rec_payload = data.decode().split("/")
				if not rec_instance_id == instance_id:
					print("received message: {} from {}".format(data, addr))
	
	time.sleep(1)