Node.js (Express): Database Connection & REST API CRUD

If you are a web developer looking to create a backend for your application using Node.js and Express, you may need to connect to a database and create a REST API for CRUD operations. In this article, we will guide you through the process of connecting to a database and implementing a REST API for CRUD operations using Node.js and Express.

Database Connection

Node.js provides a variety of libraries for connecting to different databases, such as MySQL, MongoDB, PostgreSQL, and more. One popular library for database connections in Node.js is Mongoose for MongoDB. To connect to a MongoDB database, you can use the following code:

“`javascript
const mongoose = require(‘mongoose’);

mongoose.connect(‘mongodb://localhost:27017/mydatabase’, {
useNewUrlParser: true,
useUnifiedTopology: true
})
.then(() => {
console.log(‘Connected to the database’);
})
.catch((err) => {
console.error(‘Error connecting to the database’, err);
});
“`

REST API CRUD Operations

After connecting to the database, you can create a REST API for CRUD operations using Express. You can define routes for creating, reading, updating, and deleting data from the database. Here is an example of how to implement a REST API for a simple todo list:

“`javascript
const express = require(‘express’);
const app = express();

app.use(express.json());

// Create
app.post(‘/todos’, (req, res) => {
// Create a new todo in the database
res.send(‘Todo created’);
});

// Read
app.get(‘/todos’, (req, res) => {
// Read all todos from the database
res.send(‘List of todos’);
});

// Update
app.put(‘/todos/:id’, (req, res) => {
// Update a todo in the database
res.send(‘Todo updated’);
});

// Delete
app.delete(‘/todos/:id’, (req, res) => {
//Delete a todo from the database
res.send(‘Todo deleted’);
});

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

Conclusion

Node.js and Express make it easy to connect to a database and create a REST API for CRUD operations. With the code examples provided in this article, you should be able to get started with building your backend using Node.js and Express.

Happy coding!