Secure Your Node.js Web Application

Avoid Synchronous Code in Your Application

As you know, Node.js is built around events. The whole process is a big event machine juggling different flows. Since our main process is single threaded, any function that takes a while to execute should be done in an evented manner to avoid locking up the entire application.

If you’re used to working in other programming languages, this is a tricky concept to get accustomed with. Let’s look at an example, where we implement a recursive Fibonacci calculation and a server to allow access to it:

chp-10-dos/fibonacci.js

'use strict';

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

// Calculating fibonacci number recursively
function fibonacci(n) {
    if(n < 3) {
        return