Build Full Stack Application: Building Express API Authentication App #02

Building a full stack application involves creating both the frontend and backend components of a web application. In this tutorial, we will focus on building the backend of a web application using Node.js and Express.js to create an API with authentication capabilities.

Getting Started

Before we start building our Express API with authentication, make sure you have Node.js and npm installed on your machine. You can check if you have them installed by running the following commands in your terminal:

node -v
npm -v

If you don’t already have Node.js and npm installed, you can download them from the official Node.js website.

Building the Express API

Once you have Node.js and npm installed, you can create a new directory for your Express API and navigate into it using the terminal. Then, you can initialize a new Node.js project by running the following command:

npm init -y

This will create a package.json file in your directory, which will keep track of the dependencies for your project. Next, you can install Express.js by running the following command:

npm install express

Now that you have Express.js installed, you can create a new file called index.js and start building your Express API. You can use the following code as a starting point:


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

app.listen(3000, () => {
console.log('Server is running on port 3000');
});


Adding Authentication

To add authentication to your Express API, you can use a library like Passport.js. Passport.js provides a simple way to authenticate users using different strategies, such as local authentication, OAuth, and more. You can install Passport.js by running the following command:

npm install passport

Once you have Passport.js installed, you can create a new file called auth.js and start implementing the authentication logic. You can use the following code as a starting point:


const passport = require('passport');
const LocalStrategy = require('passport-local').Strategy;

passport.use(new LocalStrategy(
(username, password, done) => {
// Implement authentication logic here
}
));


With Passport.js, you can easily implement authentication for your Express API and ensure that only authorized users can access certain routes or resources.

Conclusion

Building a full stack application involves creating both the frontend and backend components of a web application. In this tutorial, we focused on building the backend of a web application using Node.js and Express.js to create an API with authentication capabilities. By following these steps, you can create a secure and robust backend for your web application.