Building a RESTful API with Node.js and Express.js

Introduction:

In this developer journal, we will dive into building a RESTful API using Node.js and Express.js. RESTful APIs have become a fundamental part of modern web development, enabling communication between client applications and servers. We will explore the basic setup, routing, handling requests and responses, and connecting to a database. Let's get started!

Setting Up the Project:

To begin, let's set up our project. Open your terminal and follow these steps:
1.Create a new directory for your project:

mkdir restful-api
cd restful-api

2.Initialize a new Node.js project:

npm init -y

3.Install Express.js:

npm install express

Creating the Express App:

Now that we have our project set up, let's create our Express application. Create a file named app.js in the project directory and add the following code:

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

app.use(express.json());

// We will define the routes here!!

app.listen(port, () => {
  console.log(`Server running on port ${port}`);
});

Defining Routes:

Replace the comment // We will define the routes here!! in app.js with the following code:

const books = [];

app.get('/books', (req, res) => {
  res.json(books);
});

app.post('/books', (req, res) => {
  const { title, author } = req.body;
  const book = { title, author };
  books.push(book);
  res.status(201).json(book);
});

Testing the API

Start the server by running the following command in your terminal:

node app.js

Open your favorite API testing tool (e.g., Postman, curl) and send some requests to http://localhost:3000/books. Use a GET request to retrieve all books and a POST request to add a new book.

Handling Database Integration:

We'll use MongoDB and the mongoose library. Install mongoose by running the following command:

npm install mongoose

In app.js add the following code after the -
const books = []; line

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/books', { useNewUrlParser: true, useUnifiedTopology: true })
  .then(() => {
    console.log('Connected to the database');
  })
  .catch((error) => {
    console.error('Error connecting to the database:', error);
  });

const Book = mongoose.model('Book', {
  title: String,
  author: String,
});

app.post('/books', (req, res) => {
  const { title, author } = req.body;
  const book = new Book({ title, author });
  book.save()
    .then((savedBook) => {
      res.status(201).json(savedBook);
    })
    .catch((error) => {
      res.status(500).json({ error: 'An error occurred' });
    });
});

This code connects to a local MongoDB database named "books" and defines a Book model using Mongoose. The POST route now saves the book to the database using the model.

Conclusion:

In this developer journal, I've covered the basics of building a RESTful API with Node.js and Express.js. We set up the project, defined routes, handled requests and responses, and integrated a database using MongoDB and Mongoose. This is just the beginning of what you can accomplish with Node.js and Express.js in building powerful and scalable APIs. Happy coding!
ThankYou!