📡 I Built a REST API Without Googling—The Node.js Cheat Sheet You Need!

A complete REST API with CRUD operations and best practices (and zero Googling, I swear 😄)

🧠 What’s Inside:

REST API basics for beginners
Full CRUD (Create, Read, Update, Delete) with Express.js
Clean code and best practices
Simple in-memory data storage (no DB required yet)

🚀 What is a REST API?

A REST API allows you to communicate with your backend via HTTP methods:

HTTP Method	Action	Description
GET	Read	Fetch data from the server
POST	Create	Add new data
PUT	Update	Update existing data
DELETE	Delete	Remove data from the server

📁 Folder Structure

We’re keeping things simple here:

rest-api/
├── index.js
├── data.js         # in-memory storage (mock DB)
└── routes/
    └── tasks.js    # all task routes

⚙️ Step 1: Setup Your Project

mkdir rest-api
cd rest-api
npm init -y
npm install express

🧩 Step 2: Create In-Memory Storage

data.js

let tasks = [
  { id: 1, title: "Learn Node.js" },
  { id: 2, title: "Build an API" }
];

module.exports = tasks;

🛣️ Step 3: Create Routes

routes/tasks.js

const express = require('express');
const router = express.Router();
let tasks = require('../data');

// GET all tasks
router.get('/', (req, res) => {
  res.json(tasks);
});

// GET task by ID
router.get('/:id', (req, res) => {
  const task = tasks.find(t => t.id === parseInt(req.params.id));
  task ? res.json(task) : res.status(404).json({ error: 'Not found' });
});

// POST a new task
router.post('/', (req, res) => {
  const { title } = req.body;
  const newTask = { id: tasks.length + 1, title };
  tasks.push(newTask);
  res.status(201).json(newTask);
});

// PUT (update) task
router.put('/:id', (req, res) => {
  const task = tasks.find(t => t.id === parseInt(req.params.id));
  if (!task) return res.status(404).json({ error: 'Not found' });

  task.title = req.body.title;
  res.json(task);
});

// DELETE task
router.delete('/:id', (req, res) => {
  tasks = tasks.filter(t => t.id !== parseInt(req.params.id));
  res.status(204).send();
});

module.exports = router;

🧠 Step 4: Wire It All Together

index.js

const express = require('express');
const app = express();
const taskRoutes = require('./routes/tasks');
const PORT = 3000;

// Middleware to parse JSON
app.use(express.json());

// Task routes
app.use('/api/tasks', taskRoutes);

// Home route
app.get('/', (req, res) => {
  res.send('📡 Welcome to your REST API!');
});

// Start server
app.listen(PORT, () => {
  console.log(`🚀 Server running at http://localhost:${PORT}`);
});

🔬 Step 5: Test It!

Use Postman, Insomnia, or browser to test:

➕ Create Task

POST /api/tasks

{ "title": "Write a blog post" }

📥 Get All Tasks

GET /api/tasks

🔍 Get Single Task

GET /api/tasks/1

🔁 Update Task

PUT /api/tasks/1

{ "title": "Master Node.js" }

❌ Delete Task

DELETE /api/tasks/1

✅ Best Practices You Followed

✅ Modular route handling
✅ Separation of logic and data
✅ Used proper status codes
✅ Middleware for JSON parsing
✅ Clean, readable structure