1. NodeJS

Node.js has revolutionized server-side development, empowering developers to build scalable, high-performance web applications with JavaScript – the language of the web. In this wiki, you’ll find a wealth of resources covering a wide range of topics, from the basics of asynchronous programming and event-driven architecture to advanced techniques like building RESTful APIs, microservices, and real-time applications.

1. What is Node.js?

A runtime environment to execute JavaScript outside the browser.
Built on Chrome’s V8 JavaScript engine.
Uses event-driven, non-blocking I/O.

Use Cases

Web servers
RESTful APIs
Real-time applications (e.g., chat)

3. 📁 Setting Up Node.js

Installation

Install from nodejs.org
Verify with:
Terminal window
```
node -v
npm -v
```

Initialize a Project

npm init

3. 📦 Creating a Basic HTTP Server

const http = require('http');

const server = http.createServer((req, res) => {
  res.write('Hello from Node.js server!');
  res.end();
});

server.listen(3000);

4. ✅ Handle Basic Get and Post

You can handle simple GET and POST requests using just Node.js and the http module — no Express needed.

4.1 Basic GET and POST Handling

const http = require('http');

const server = http.createServer((req, res) => {
  const { method, url } = req;

  // Set content type
  res.setHeader('Content-Type', 'application/json');

  if (method === 'GET' && url === '/') {
    res.writeHead(200);
    res.end(JSON.stringify({ message: 'Hello from GET!' }));

  } else if (method === 'POST' && url === '/data') {
    let body = '';

    // Collect the POST data
    req.on('data', chunk => {
      body += chunk.toString();
    });

    // Handle end of data
    req.on('end', () => {
      const parsedData = JSON.parse(body);
      res.writeHead(200);
      res.end(JSON.stringify({
        message: 'Received POST data!',
        data: parsedData
      }));
    });

  } else {
    res.writeHead(404);
    res.end(JSON.stringify({ error: 'Not found' }));
  }
});

server.listen(3000, () => {
  console.log('Server running on http://localhost:3000');
});

4.2 Testing It

GET request:
Visit http://localhost:3000/ in your browser → responds with JSON.
POST request (e.g. using curl or Postman):

curl -X POST http://localhost:3000/data \
  -H "Content-Type: application/json" \
  -d '{"name":"Nadith", "age":17}'

Enter Password