How can we use MQTT protocol to send messages over micropython(esp32) board?
Concepts Basically, you got two actions available. One is publish . Another is subscribe . If we want to send some message out to others, we need to use publish . If we want to just receive messages from others, we use subscribe . publish from umqtt.simple import MQTTClient c = MQTTClient( "clients/a" , SERVICE_IP) c.connect() c.publish( b"a_topic" , b"hello" ) c.disconnect() subscribe import time from umqtt.simple import MQTTClient # Received messages from subscriptions will be delivered to this callback def callback (topic, msg) : print((topic, msg)) c = MQTTClient( "clients/b" , SERVICE_IP) c.set_callback(callback) c.connect() c.subscribe( b"a_topic" ) while True : if True : # Blocking wait for message c.wait_msg() else : # Non-blocking wait for message c.check_msg() # Then need to sleep to avoid 100% CPU usage (in a real # app other useful actions woul...
