MicroPython MQTT subscribe

umqtt_sub.py

try:
    from umqtt.robust import MQTTClient
except ImportError:
    import upip
    upip.install(['umqtt.robust', 'umqtt.simple'])
    from umqtt.robust import MQTTClient


SERVER = '127.0.0.1'
USER = 'mqtt-test'
PASSWORD = 'password!'
DEBUG = True


def sub_cb(topic, msg):
    print((topic, msg))


def main():
    c = MQTTClient('client1', SERVER, user=USER, password=PASSWORD)
    c.DEBUG = DEBUG
    c.set_callback(sub_cb)
    if not c.connect(clean_session=False):
        c.subscribe(b'test_topic')
    while True:
        c.wait_msg()
    # c.disconnect()


if __name__ == '__main__':
    main()