HTTP methods for CRUD operations in Express - Mini Project: Build & Apply

HTTP methods for CRUD operations

📖 Scenario: You are building a simple Express server to manage a list of books. Each book has an id and a title. You want to allow users to create, read, update, and delete books using HTTP methods.

🎯 Goal: Create an Express app that supports CRUD operations on a books array using the correct HTTP methods: GET, POST, PUT, and DELETE.

📋 What You'll Learn

Create an array called books with two book objects having id and title.

Add a variable called nextId to track the next book ID.

Create a GET route at /books to return all books.

Create a POST route at /books to add a new book with a unique id.

Create a PUT route at /books/:id to update the title of a book by id.

Create a DELETE route at /books/:id to remove a book by id.

💡 Why This Matters

🌍 Real World

Web servers often use HTTP methods to manage data resources like users, products, or posts. This project shows how to build a simple API for managing books.

💼 Career

Understanding HTTP methods and Express routing is essential for backend web development jobs, API design, and full-stack roles.

1

Create the initial books array

Create an array called books with two objects: { id: 1, title: '1984' } and { id: 2, title: 'Brave New World' }.

Express

// Create the books array with two book objects
// Your code here

Need a hint?

Use const books = [ ... ] with two objects inside.

2

Add a nextId variable

Add a variable called nextId and set it to 3 to track the next book ID.

Express

const books = [
  { id: 1, title: '1984' },
  { id: 2, title: 'Brave New World' }
];

// Add nextId variable here
// Your code here

Need a hint?

Use let nextId = 3; to allow incrementing later.

3

Create GET and POST routes

Create a GET route at /books that sends the books array as JSON. Then create a POST route at /books that adds a new book with a unique id from nextId and increments nextId. Use req.body.title for the new book's title.

Express

const books = [
  { id: 1, title: '1984' },
  { id: 2, title: 'Brave New World' }
];

let nextId = 3;

// Create GET /books route
// Create POST /books route
// Your code here

Need a hint?

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

4

Create PUT and DELETE routes

Create a PUT route at /books/:id that updates the title of the book with the matching id from req.params.id. Then create a DELETE route at /books/:id that removes the book with the matching id. Use res.status(204).end() after deletion.

Express

const books = [
  { id: 1, title: '1984' },
  { id: 2, title: 'Brave New World' }
];

let nextId = 3;

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

app.post('/books', (req, res) => {
  const newBook = { id: nextId++, title: req.body.title };
  books.push(newBook);
  res.status(201).json(newBook);
});

// Create PUT /books/:id route
// Create DELETE /books/:id route
// Your code here

Need a hint?

Use app.put('/books/:id', ...) to find and update the book, and app.delete('/books/:id', ...) to remove it.