Library Management System

A full-fledged CRUD application for managing a library system, built with Node.js, Express, TypeScript, and MongoDB. This project implements Object-Oriented Programming (OOP) principles with a layered architecture: Controllers → Services → Repositories.

Features

• Books Management: Create, Read (List + Detail), Update, Delete (CRUD)
• Search: Search books by title/author/genre.
• Authentication: User registration and login with JWT.
• Authorization: Role-based access control (Admin vs. Member).
• Validation: Strict input validation using Mongoose schemas.
• Architecture: Clean OOP structure with manual dependency handling.

Tech Stack

• Runtime: Node.js
• Language: TypeScript
• Framework: Express.js
• Database: MongoDB (with Mongoose ODM)
• Auth: JWT & Bcrypt

Project Structure

src/
├── controllers/  # Handle HTTP requests and responses
├── services/     # Business logic layer
├── repositories/ # Database access layer
├── models/       # Mongoose schemas and interfaces
├── routes/       # API route definitions
├── middlewares/  # Express middlewares (Auth, Error)
├── utils/        # Utility functions and interfaces
├── app.ts        # Express app setup
└── server.ts     # Entry point

Setup & Run

1. Install Dependencies:

   npm install

2. Environment Variables: A .env file is created with default values:

   PORT=3000
   MONGO_URI=mongodb://localhost:27017/library_system
   JWT_SECRET=supersecretkey_library_ops
   

3. Start Server:

   • Development:

     npm run dev

   • Production Build:

     npm run build
     npm start

API Endpoints

Auth

• POST /api/auth/register - Register a new user
• POST /api/auth/login - Login and get JWT

Books

• GET /api/books - Get all books (supports ?search=term)
• GET /api/books/:id - Get book details
• POST /api/books - Create a book (Admin only, requires Header Authorization: Bearer <token>)
• PUT /api/books/:id - Update a book (Admin only)
• DELETE /api/books/:id - Delete a book (Admin only)