Multiple Subscribers to One Publisher

multi_sub.py

# multi_sub.py

import zmq
from threading import Thread

host = "127.0.0.1"
port = "5001"

ctx = zmq.Context()

# simple function to receive the 'light' publisher's messages
def on_light_status(appliance):
    socket = ctx.socket(zmq.SUB)
    socket.connect(f"tcp://{host}:{port}")
    socket.subscribe("light")

    light_msg = socket.recv_string()
    print(f"{appliance} received '{light_msg}' from light.")

coffee_maker = Thread(target=on_light_status, args=("COFFEE MAKER",))
toaster = Thread(target=on_light_status, args=("TOASTER",))

coffee_maker.start()
toaster.start()

# waits for both to receive messages before exiting
coffee_maker.join()
toaster.join()

single_pub.py

# single_pub.py

import time
import zmq

host = "127.0.0.1"
port = "5001"

# Creates a socket instance
context = zmq.Context()
socket = context.socket(zmq.PUB)

# Binds the socket to a predefined port on localhost
socket.bind(f"tcp://{host}:{port}")

time.sleep(1)

# Sends a string message
socket.send_string("light is ON")