Case Study: REST API with Node.js

1. Introduction

This lesson focuses on building a RESTful API using Node.js, a popular JavaScript runtime built on Chrome's V8 JavaScript engine. We will explore key concepts, implementation steps, and best practices for developing and integrating REST APIs.

2. Key Concepts

• REST (Representational State Transfer) - An architectural style for designing networked applications.
• HTTP Methods - The primary methods used are GET, POST, PUT, DELETE.
• Endpoints - Specific URLs where API resources can be accessed.
• JSON - A lightweight data interchange format that's easy for humans to read and write.

3. Setup

To get started, ensure you have Node.js and npm installed on your machine.

1. Install Node.js from nodejs.org.
2. Create a new directory for your project and navigate into it:

mkdir my-api && cd my-api

3. Initialize a new Node.js project:

npm init -y

4. Install Express.js, a popular web framework for Node.js:

npm install express

4. Implementation

Now we will create a simple REST API that manages a list of items.

4.1 Create the API

In your project directory, create a file named app.js and add the following code:

const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;

app.use(express.json());

let items = [];

// GET all items
app.get('/api/items', (req, res) => {
    res.status(200).json(items);
});

// POST a new item
app.post('/api/items', (req, res) => {
    const item = req.body;
    items.push(item);
    res.status(201).json(item);
});

// DELETE an item
app.delete('/api/items/:id', (req, res) => {
    const { id } = req.params;
    items = items.filter(item => item.id !== parseInt(id));
    res.status(204).send();
});

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

Run the server using:

node app.js

5. Best Practices

• Use proper HTTP status codes for responses.
• Validate request data to ensure it meets your API's requirements.
• Implement error handling to provide meaningful error messages.
• Use versioning in your API to manage changes over time.

6. FAQ