📘 Lecture 1 – Node.js File System Module (fs)

This lecture introduces basic file system operations in Node.js using the built-in fs module. Both asynchronous and synchronous methods are demonstrated.

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📄 Topics Covered

✅ 1. Writing to Files

• Asynchronously using fs.writeFile()
• Synchronously using fs.writeFileSync()

✅ 2. Reading from Files

• Asynchronously using fs.readFile()
• Synchronously using fs.readFileSync()

✅ 3. Copying Files

• Using fs.copyFileSync()

✅ 4. Deleting Files

• Using fs.unlinkSync()

✅ 5. Getting File Info (Commented)

• Using fs.statSync()

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📘 Lecture 2 – Creating a Basic HTTP Server in Node.js

This lecture demonstrates how to create a basic HTTP server using Node.js' built-in http and url modules.

🔧 Key Concepts Used:

• http.createServer() – Creating a web server

• url.parse() – Parsing URL and extracting pathname and query parameters

• fs.appendFile() – Logging requests to server.log

• switch-case – Handling multiple routes

⚙️ What This Server Does:

• Logs each incoming request with timestamp to server.log

• Responds to different routes:

• / → Home page response

• /about?myname=YourName → About page with dynamic name

• /contact → Contact page response

• Any other path → 404 message

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📘 Lecture 3 – Introduction to Express.js

In this lecture, you set up a basic web server using the popular Express.js framework for Node.js. It simplifies routing and handling HTTP requests.

🔧 Key Concepts Used:

• express() – Initializes the express app

• app.get() – Handles GET requests on specific routes

• req.query – Accesses query parameters from the URL

• res.send() – Sends a response to the client

🌐 What This Server Does:

Responds to:

• / → Returns a static message from the Home page

• /about?name=YourName → Returns a dynamic message from the About page using query param name

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📘 Lecture 4 – RESTful API with Express, MongoDB (Mongoose) & MVC Architecture

In this lecture, the application is refactored into an MVC (Model-View-Controller) structure while connecting to a MongoDB database using Mongoose. The project includes custom middleware for logging and full CRUD operations for users.

🛠 Features Implemented

• MVC Architecture

  • Models – Define database schema and interact with MongoDB.
  • Views – Render HTML responses.
  • Controllers – Contain route logic for handling requests and responses.
  • Routes – Organize API endpoints.
  • Middleware – Reusable functions (logging requests).

• MongoDB Connection via Mongoose.

• Request Logging Middleware – Logs request date, time, and path in logs.txt.

• User CRUD API :-

  • Create, Read, Update, and Delete users.
  • HTML view for displaying users.

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📌 Lecture-5: URL Shortener Project

In this lecture, I built a URL Shortener service using Node.js, Express.js, and MongoDB. The project allows you to:

• Create short URLs from long links.
• Redirect users from a short URL to the original URL.
• Track analytics (click count + visit history with timestamps).

⚙️ Features

1. Create Short URL
2. Redirect to Original URL
3. Get Analytics

🛠 Tech Stack

• Node.js – Backend runtime
• Express.js – Routing and middleware
• MongoDB + Mongoose – Database and ORM
• shortid – For generating unique short IDs

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📘 Lecture 5 – URL Shortener with Authentication & Admin Authorization

This project builds a fully functional URL Shortener API with:

• 🔐 JWT-based user authentication
• 🧑‍💻 Role-based access (admin/user)
• 🔗 Short URL generation
• ↩️ Redirection to original URLs
• 📈 Visit history + click analytics
• 🧱 Built using clean MVC architecture

🚀 Features

✅ Register/Login Users can create accounts and receive a JWT token ✅ Auth Middleware Custom middleware validates JWT for protected routes ✅ URL Shortening Users can shorten any long URL ✅ Redirection Visiting short URL redirects to the original ✅ Analytics Tracks each visit with timestamp ✅ Admin Panel Admin can fetch all shortened URLs from all users ✅ Clean Architecture MVC: routes, controllers, models, middleware separated

🔐 Authentication & Authorization

• JWT-based login: Upon login, users receive a token to access protected routes.
• Roles:
  • user – Can shorten URLs, view own analytics
  • admin – Can view all URLs generated by any user
• Custom Middleware:
  • authenticateUser – Verifies JWT -authorizeAdmin – Ensures only admin accesses admin-only routes

🧠 Tech Stack

Node JS

Express JS

MongoDB

JWT (jsonwebtoken)

shortid (for short URL generation)

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