Building REST API with MongoDB, Express.js, and Node.js

Building a REST API with MongoDB, Express.js, and Node.js is a complete backend development process. This combination is commonly known as the MERN backend stack. In this lesson, you will learn how to connect MongoDB with Express.js and Node.js to create a fully functional API.

Setup Project for API Development

Install Required Packages

npm init -y
npm install express mongoose

Basic Server Setup

const express = require(‘express’);
const mongoose = require(‘mongoose’);

const app = express();
app.use(express.json());

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

Connect MongoDB with Mongoose

Database Connection

mongoose.connect(‘mongodb://localhost:27017/mydb’)
.then(() => console.log(‘MongoDB connected’))
.catch(err => console.log(err));

Create Schema and Model

User Schema

const userSchema = new mongoose.Schema({
name: String,
age: Number
});

User Model

const User = mongoose.model(‘User’, userSchema);

Create REST API Routes

Create User API (POST)

app.post(‘/users’, async (req, res) => {
const user = new User(req.body);
await user.save();
res.json(user);
});

Get All Users API (GET)

app.get(‘/users’, async (req, res) => {
const users = await User.find();
res.json(users);
});

Get Single User API (GET by ID)

app.get(‘/users/:id’, async (req, res) => {
const user = await User.findById(req.params.id);
res.json(user);
});

Update User API (PUT)

app.put(‘/users/:id’, async (req, res) => {
const user = await User.findByIdAndUpdate(req.params.id, req.body, { new: true });
res.json(user);
});

Delete User API (DELETE)

app.delete(‘/users/:id’, async (req, res) => {
await User.findByIdAndDelete(req.params.id);
res.send(‘User deleted’);
});

Complete API Flow

This API allows you to create, read, update, and delete users using MongoDB, Express.js, and Node.js. It is a real-world backend structure used in many applications.

Best Practices for Building API

Use Async Await

Handle database operations properly

Validate Data

Always validate user input

Use Proper Status Codes

Send correct HTTP responses

Organize Code

Separate routes, models, and controllers

Real-World Use of MERN Backend

This structure is used in applications like e-commerce platforms, admin dashboards, and mobile apps. It is one of the most in-demand backend skills.

FAQs on Building API with MongoDB and Express.js

How to build API in Node.js

You can build API using Express.js and connect it with MongoDB using Mongoose.

What is MERN stack

MERN stack includes MongoDB, Express.js, React, and Node.js.

Is MongoDB good for API development

Yes, MongoDB is widely used for building scalable APIs.

Continue Learning Backend Development

Now that you understand how to build a REST API with MongoDB, Express.js, and Node.js, you are ready to move to the next lesson where you will learn about authentication and JWT in Node.js. To explore more structured tutorials and courses, click here for more free courses.