const mqtt = require('mqtt');
var Topic = '#'; //subscribe to all topics
var options = {
    clientId: 'MyMQTT',
    port: 1883,
    keepalive: 60
};

const client = mqtt.connect({
    host: 'localhost',
    port: 1883
});

client.on('connect', mqtt_connect);
client.on('reconnect', mqtt_reconnect);
client.on('error', mqtt_error);
client.on('message', mqtt_messsageReceived);
client.on('close', mqtt_close);

function mqtt_connect() {
    console.log("Connecting MQTT");
    client.subscribe(Topic, mqtt_subscribe);
}

function mqtt_subscribe(err, granted) {
    console.log("Subscribed to " + Topic);
    if (err) {
        console.log(err);
    }
}

function mqtt_reconnect(err) {
    console.log("Reconnect MQTT");
    if (err) {
        console.log(err);
    }
    client = mqtt.connect(Broker_URL, options);
}

function mqtt_error(err) {
    console.log("Error!");
    if (err) {
        console.log(err);
    }
}

function after_publish() {
    //do nothing
}

function mqtt_messsageReceived(topic, message, packet) {
    console.log('Topic=' + topic + '  Message=' + message);
}

function mqtt_close() {
    console.log("Close MQTT");
}