How to Build Your First REST API with Node.js and Express (From Someone Who Was Scared at First)

I still remember the first time I opened an empty app.js file in VS Code. No idea where to start. REST API? I barely understood what "route" meant. But I kept going, This is the guide I wish I had when I started my journey into backend development. 1. What is a REST API Think of a REST API like a restaurant experience. You (the client) sit at a table and look at a menu (the API documentation). When you're ready to order, you call over a waiter (send a request) who takes your order to the kitchen (server). The kitchen prepares your food (processes the request), and the waiter returns it (the response). In this analogy: GET is like asking, "What's the special today?" POST is like placing a new order PUT is like saying, "Actually, can I change my side dish?" DELETE is like canceling your order That's REST in a nutshell - a set of conventions for requesting and modifying resources over HTTP. 2. Setting Up Node.js and Express First, make sure you have Node.js installed (check with node -v in your terminal). Then: Create a new folder for your project and navigate to it: mkdir my-first-api cd my-first-api Initialize a Node.js project: npm init -y Install Express: npm install express Create your main file: touch app.js Open app.js and add the following code: const express = require('express'); const app = express(); const PORT = 3000; // Middleware to parse JSON bodies app.use(express.json()); app.listen(PORT, () => { console.log(`Server running on http://localhost:${PORT}`); }); 3. Creating Your First Route Let's add a simple welcome route to make sure everything's working: app.get('/api/welcome', (req, res) => { res.json({ message: "Hello, world!" }); }); Now run your server: node app.js Open your browser and navigate to http://localhost:3000/api/welcome. You should see: {"message":"Hello, world!"}. Congratulations! You've created your first API endpoint!

May 2, 2025 - 00:19

How to Build Your First REST API with Node.js and Express (From Someone Who Was Scared at First)

I still remember the first time I opened an empty app.js file in VS Code. No idea where to start. REST API? I barely understood what "route" meant.
But I kept going, This is the guide I wish I had when I started my journey into backend development.

1. What is a REST API

Think of a REST API like a restaurant experience. You (the client) sit at a table and look at a menu (the API documentation). When you're ready to order, you call over a waiter (send a request) who takes your order to the kitchen (server). The kitchen prepares your food (processes the request), and the waiter returns it (the response).

In this analogy:

GET is like asking, "What's the special today?"
POST is like placing a new order
PUT is like saying, "Actually, can I change my side dish?"
DELETE is like canceling your order

That's REST in a nutshell - a set of conventions for requesting and modifying resources over HTTP.

2. Setting Up Node.js and Express

First, make sure you have Node.js installed (check with node -v in your terminal). Then:

Create a new folder for your project and navigate to it:

mkdir my-first-api
cd my-first-api

Initialize a Node.js project:

npm init -y

Install Express:

npm install express

Create your main file:

touch app.js

Open app.js and add the following code:

const express = require('express');
const app = express();
const PORT = 3000;

// Middleware to parse JSON bodies
app.use(express.json());

app.listen(PORT, () => {
  console.log(`Server running on http://localhost:${PORT}`);
});

3. Creating Your First Route

Let's add a simple welcome route to make sure everything's working:

app.get('/api/welcome', (req, res) => {
  res.json({ message: "Hello, world!" });
});

Now run your server:

node app.js

Open your browser and navigate to http://localhost:3000/api/welcome. You should see: {"message":"Hello, world!"}. Congratulations! You've created your first API endpoint!