node_helper.js

const mqtt = require("mqtt");
const NodeHelper = require("node_helper");
var node_helper_config;

module.exports = NodeHelper.create({
  start: function () {
    console.log(this.name + ": Starting node helper");
    this.loaded = false;
  },

  makeServerKey: function (address, port, user) {
    return "" + address + ":" + (port | ("1883" + user));
  },

  log: function (...args) {
    if (node_helper_config.logging) {
      console.log(args);
    }
  },

  formatDateTime: function (secs) {
    this.log("Secs", secs);
    var epoch = new Date(0);
    epoch.setSeconds(parseInt(secs));
    this.log("Epoch", epoch);
    var date = epoch.toISOString();
    this.log("date", date);
    this.log(
      "toLocaleTime",
      epoch.toLocaleTimeString(node_helper_config.localeStr)
    );
    var dateStr = date.split(".")[0].split("T")[0];
    return (
      dateStr.split("-")[2] +
      "." +
      dateStr.split("-")[1] +
      " " +
      epoch.toLocaleTimeString(node_helper_config.localeStr).split(":")[0] +
      ":" +
      epoch.toLocaleTimeString(node_helper_config.localeStr).split(":")[1]
    );
  },

  startClient: function (config) {
    node_helper_config = config;

    console.log(
      this.name + ": Starting client for: ",
      config.mqttServerAddress
    );

    var self = this;

    var serverKey = this.makeServerKey(
      config.mqttServerAddress,
      config.mqttServerPort,
      config.mqttServerUser
    );
    var server = {};

    server.serverKey = serverKey;
    server.address = config.mqttServerAddress;
    server.port = config.mqttServerPort;
    server.options = {};
    if (config.mqttServerUser) server.options.username = config.mqttServerUser;
    if (config.mqttServerPassword)
      server.options.password = config.mqttServerPassword;
    server.topics = [
      config.mqttTopic + "/latitude",
      config.mqttTopic + "/longitude"
    ];

    var mqttServer =
      (server.address.match(/^mqtts?:\/\//) ? "" : "mqtt://") + server.address;
    if (server.port) {
      mqttServer = mqttServer + ":" + server.port;
    }
    console.log(self.name + ": Connecting to " + mqttServer);

    server.client = mqtt.connect(mqttServer, server.options);

    server.client.on("error", function (err) {
      console.log(self.name + " " + server.serverKey + ": Error: " + err);
    });

    server.client.on("reconnect", function (err) {
      server.value = "reconnecting"; // Hmmm...
      console.log(self.name + ": " + server.serverKey + " reconnecting");
    });

    server.client.on("connect", function (connack) {
      console.log(self.name + " connected to " + mqttServer);
      console.log(self.name + ": subscribing to " + server.topics);
      server.client.subscribe(server.topics);
    });

    server.client.on("message", function (topic, payload) {
      self.log(self.name + " " + topic, payload.toString());
      var now = Date.now();
      var nowStr = self.formatDateTime(now / 1000);
      self.log(self.name, topic, now, nowStr);
      self.sendSocketNotification("MQTT_PAYLOAD", {
        serverKey: server.serverKey,
        topic: topic,
        value: payload.toString(),
        time: now,
        timeStr: nowStr
      });
    });
  },

  socketNotificationReceived: function (notification, payload) {
    var self = this;
    console.log(
      self.name + " Notification received: " + notification + " " + payload
    );

    if (notification === "MQTT_CONFIG") {
      var config = payload;
      console.log(self.name + " MQTT_CONFIG: " + config);
      self.startClient(config);
      self.loaded = true;
    }
  }
});