Node.js Get Started

Getting Started with Node.js

Node.js is a JavaScript runtime built on Chrome's V8 engine. It allows you to run JavaScript outside the browser, making it ideal for backend development, command-line tools, and API services.

1. Install Node.js

Download and install Node.js from the official website. It comes with npm (Node Package Manager) by default.

2. Check Installation

Verify that Node.js and npm are installed by running:

node -v
npm -v

3. Run Your First Node.js Program

Create a file app.js and add the following code:

console.log("Hello, Node.js!");

Run it using:

node app.js

4. Using Built-in Modules

Node.js provides core modules like fs, http, and path. Example:

const fs = require('fs');
fs.writeFileSync('test.txt', 'Hello from Node.js');
console.log('File created!');

5. Create a Simple HTTP Server

const http = require('http');

const server = http.createServer((req, res) => {
    res.writeHead(200, { 'Content-Type': 'text/plain' });
    res.end('Hello, World!');
});

server.listen(3000, () => console.log('Server running on port 3000'));

Run the script and visit http://localhost:3000 in your browser.

6. Install Packages with npm

npm init -y        
npm install express

7. Create a Basic Express Server

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

app.get('/', (req, res) => {
    res.send('Hello, Express!');
});

app.listen(3000, () => console.log('Express server running on port 3000'));

8. Run Scripts with package.json

Modify package.json to add a script:

"scripts": {
  "start": "node app.js"
}

Run it using:

npm start

9. Use Nodemon for Auto-Reloading

Install and use Nodemon for development:

npm install -g nodemon
nodemon app.js

10. Next Steps

• Explore asynchronous programming with callbacks, promises, and async/await.
• Work with databases like MongoDB, PostgreSQL, or MySQL.
• Build REST APIs with Express.js.
• Deploy your application using Docker, AWS, or Heroku.