micropython mqtt.simple example with HiveMQ broker

mqtt_simple_hivemq_example.py

import time
import network
from umqtt.simple import MQTTClient

network_config = {"ssid": "<ssid>", "wifi_pw": "<wifi_pw>"}
sta_if = network.WLAN(network.STA_IF)
sta_if.active(True)
sta_if.connect(network_config["ssid"], network_config["wifi_pw"])
time.sleep(5)
sta_if.ifconfig()


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


config = {}
config["client_id"] = "uPy-client-3943"
config["port"] = 8883
config["server"] = "48c156647b6a4157b8f16210196bb4bf.s2.eu.hivemq.cloud"
config["user"] = "uPy-test-client"
config["password"] = "TestClientCredentialsForExample"
config["keepalive"] = 60
config["ssl"] = True
config["ssl_params"] = {
    "server_hostname": "48c156647b6a4157b8f16210196bb4bf.s2.eu.hivemq.cloud"
}


def main(config=config):
    client = MQTTClient(**config)
    client.set_callback(sub_cb)
    client.connect()
    client.subscribe("foo")
    val = 0
    while True:
        try:
            client.publish("result", f"Result: {val}")
            print(f"Published: result - {val}")
            client.check_msg()
            val += 1
            time.sleep(5)
        except KeyboardInterrupt:
            print("Ended by user")
            client.disconnect()
            break
        except Exception as err:
            print("Error encountered:")
            print(err)
            break
if __name__=="__main__":
    main(config)