Node.js Learning Summary

Project Setup

1. Initialize Project

   npm init -y

   • Creates a package.json file to manage dependencies and scripts.

2. Project Structure

   • Created utils.js for utility functions.
   • Added controller files for handling logic.

3. Modify package.json

   • Updated package.json for better project organization. add "type": "module", right after "main": "index.js" delete "type": commonjs

Development Tools

1. Install Nodemon (for auto-restart in development)

   npm install -D nodemon --save-dev

2. Update package.json to run server in development mode

   "scripts": {
     "dev": "nodemon index.js"
   }

   • Run using:

     npm run dev

Environment & Git

1. Create .gitignore

   • Ignore node_modules, .env, and other unnecessary files.

2. Environment Variables (.env file)

   • Store sensitive configuration data.

Node.js Core Modules

1. Handling Requests

   • GET, POST, PUT, DELETE requests using built-in http module.

2. File System (fs) Module

   • Read and write files asynchronously.

   const fs = require('fs');
   fs.writeFileSync('test.txt', 'Hello, Node.js!');

3. Hashing & Encryption

   • Secure data using crypto module.

4. Operating System (os) Module

   • Fetch system details like memory and CPU.

   const os = require('os');
   console.log(os.platform(), os.freemem());

5. Path Module

   • Manage file and directory paths.

   const path = require('path');
   console.log(path.join(__dirname, 'utils.js'));

6. URL Module

   • Parse and manipulate URLs.

   const url = require('url');
   const myUrl = new URL('https://example.com/path?name=John');
   console.log(myUrl.searchParams.get('name'));

7. Events Module

   • Handle event-driven programming.

   const EventEmitter = require('events');
   const emitter = new EventEmitter();
   emitter.on('message', () => console.log('Event triggered!'));
   emitter.emit('message');

8. Process Object

   • Access environment variables and process information.

   console.log(process.env.PATH);