In the previous recipes, we created a simple web server application to read data from a given pin on the board, or to control a given pin. However, this is not convenient, as you always need to change the code every time you change the pin you want to control.

Here, we are going to learn how to create an API so that you can control any pin on the board from a web browser.

// Required modules
var m = require("mraa");
var util = require('util');

var express = require('express');
var app = express();

// API routes
app.get('/api/read', function (req, res) {

  // Get pin
  var pin = req.query.pin;

  // Return...