UDPClient.py

import serial
import socket
import time
FROM_GATEWAY    = 0
FIRE_ALARM      = 1
API_VERSION     = 2
MODE            = 3
DURATION        = 4
def get_host_ip():
	try:
		s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
		s.connect(('8.8.8.8',80))
		ip = s.getsockname()[0]
	finally:
		s.close()
	return ip
def alert_operation(mode, duration):
	if(mode == 1):
		conn.write('RO')
		time.sleep(duration)
		conn.write('FQ')
	elif(mode == 2):
		conn.write('1P')
		time.sleep(duration)
		conn.write('FQ')
	elif(mode == 3):
		conn.write('RO1P')
		time.sleep(duration)
		conn.write('FQ')
	else: 
		print('unrecognized mode')

# setup serial port
conn = serial.Serial('/dev/ttyUSB0',timeout=.2)
time.sleep(3)
conn.write('FQ')

# setup UDP client port
IP = get_host_ip()
serverAddressPort   = (IP, 20001)
bufferSize  = 1024
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind(serverAddressPort)
print('Start UDP Server Listening at port: {}'.format(IP))

while True:
	bytesAddressPair = sock.recvfrom(bufferSize)
	
	# print(bytesAddressPair[0], bytesAddressPair[1])
	message = bytesAddressPair[0]
	address = bytesAddressPair[1]
	API_ver = None
	print('received message: {}, from: {}'.format(message, address))
	splitted_message = message.split(';')
	if(splitted_message[FROM_GATEWAY] != '6'):
		print('Data aren\'t from Gateway')
		continue
	elif(splitted_message[FIRE_ALARM] != '7'):
		print('FIRE_ALARM Error')
		continue
	else:
		API_ver = splitted_message[API_VERSION]
		mode = int(splitted_message[MODE])
		duration = int(splitted_message[DURATION])
		alert_operation(mode, duration)
	# time.sleep(0.3)