Processing commands that interact with actuators in Node.js

Now that we have coded the iOS app that will allow the user to turn on and turn off a motor, we will write the Node.js code that will control the motor wired to the IoT board. We can run Node.js and the code in any computer or IoT board capable of running Node.js version 6.9.x or higher.

For this example, we specified in the requirements that the motors would be wired to the following IoT boards: Raspberry Pi 3, Raspberry Pi 2 Model B, Intel Edison, Intel Galileo Gen 2, Intel Joule 570x, and Intel Joule 550x. All of these boards can have Node.js installed and run the sample code. However, we can also run the code on many other IoT boards or even on our development computer.

In this example, we will use the MQTT.js open source library to work with direct MQTT with Node.js. Make sure you have Node.js installed in the computer or IoT board you will use to run this example. If you haven't worked with the example in the previous chapter...