MQTT nodejs connect

index.js

var mqtt = require('mqtt');

var url = "mqtts://localhost";

var options = {
	port: 8883,
	clientId: 'mqttjs_' + Math.random().toString(16).substr(2, 8),
	username: '',
	password: '',
};

// Create a client connection
var client = mqtt.connect(url, options);

client.on('connect', function() { // When connected

  // subscribe to a topic
  client.subscribe('test', function() {
    // when a message arrives, do something with it
    client.on('message', function(topic, message, packet) {
      console.log("Received '" + message + "' on '" + topic + "'");
    });
  });

  // publish a message to a topic
  client.publish('test', 'my message', function() {
    console.log("Message is published");
    client.end(); // Close the connection when published
  });
});