tradfri-monitor.js

const tradfriLib = require("node-tradfri-client");
const TradfriClient = tradfriLib.TradfriClient;
const AccessoryTypes = tradfriLib.AccessoryTypes;
const tradfri = new TradfriClient("192.168.100.101");

const lightbulbs = {};
const plugs = {};
const devices = {};

const connect = async () => {
  try {
    await tradfri.connect('USERNAME', 'PASSWORD');

    tradfri
      .on("device updated", tradfri_deviceUpdated)
      .observeDevices();
  } catch (e) {
    console.log(e);
  }
}

function tradfri_deviceUpdated(device) {
  devices[device.instanceId] = device;

  if (device.type === AccessoryTypes.lightbulb) {
    lightbulbs[device.instanceId] = device;
  } else if (device.type === AccessoryTypes.plug) {
    plugs[device.instanceId] = device;
  }
}

connect();