light publisher.py

import paho.mqtt.client as mqtt
import time

def on_connect(client, userdata, flags, rc):   #client method to connect
    if rc == 0:
        client.connected_flag = True           #set the flag    
        print("Connected, returned code ", rc) #check to know if we are connected to broker
    else:
        print("Bad connection, returned code= ", rc)  #if connection failed

def on_disconnect(client, userdata, mid):
    print("Client disconnected ok")
    time.sleep(1)                   #wait before retrying connection

# callback function when a PUBLISH message is received from the MQTT server
def on_message(client, userdata, message):
    print("Received message: ", str(message.payload.decode("utf-8")))
    if message.payload.decode("utf-8") == "GREEN" :
        print("Turning Light bulb ON now...")
    else :
        print("Turning Light bulb OFF now...")

client2 = mqtt.Client(mqtt.CallbackAPIVersion.VERSION1,"light-sensor bulbs")
client2.on_connect =  on_connect         #registers the on_connect function with the client
client2.connect('broker.hivemq.com',1883)   #connect the client to the broker at an appropriate project
client2.disconnect = on_disconnect
client2.on_message = on_message

while True:      
    client2.loop_start()                           #start the loop      
    client2.subscribe("House/Light")