Scripts for testing UDP multicast on ESP8266

esp8266-sender.py

#!/usr/bin/env python
# encoding: utf-8

import network
import socket

sta = network.WLAN(network.STA_IF)
sta.active(True)
sta.connect('ESSID', 'key')

# Enabling STA_IF is not enough, as the AP interface continues to run and MicroPython
# treats it as the default interface and sends all multicast packets using it.
# Disabling it forces the multicast packets to get sent over the STA interface.
# See https://github.com/micropython/micropython/issues/2198
ap = network.WLAN(network.AP_IF)
ap.active(False)

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(('', 1900))
s.sendto(b'some unicast data', ('your-local-machine-ip', 1900))
s.sendto(b'some multicast data', ('239.255.255.250', 1900))

pc-receiver-multicast.py

#!/usr/bin/env python
# encoding: utf-8

import socket
import struct

MCAST_GRP = '239.255.255.250'
MCAST_PORT = 1900

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((MCAST_GRP, MCAST_PORT))
mreq = struct.pack("4sl", socket.inet_aton(MCAST_GRP), socket.INADDR_ANY)
s.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

try:
    while True:
        print("waiting for data...")
        data, addr = s.recvfrom(100)
        print(data, addr)
except KeyboardInterrupt:
    pass

s.close()

pc-receiver-unicast.py

#!/usr/bin/env python
# encoding: utf-8

import socket
import struct

PORT = 1900

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(('', PORT))

try:
    while True:
        print("waiting for data...")
        data, addr = s.recvfrom(100)
        print(data, addr)
except KeyboardInterrupt:
    pass

s.close()