User-Authentication-Authorization-System

🔐 Auth System – Spring Boot JWT Authentication

A Spring Boot Authentication & Authorization System built using JWT (JSON Web Token) and Spring Security. This project demonstrates user registration, login, role-based access control, and secure REST APIs following clean layered architecture.

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🚀 Features

• User Registration & Login
• JWT-based Authentication
• Role-based Authorization (USER / ADMIN)
• Password Encryption (BCrypt)
• Secured REST APIs
• Global Exception Handling
• Clean Architecture (Controller, Service, Repository)
• MySQL / H2 compatible

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🛠 Tech Stack

• Java 17
• Spring Boot
• Spring Security
• JWT (JSON Web Token)
• Spring Data JPA (Hibernate)
• MySQL / H2
• Maven
• Postman (API Testing)

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📂 Project Structure

auth-system/
│
├── controller/
│   ├── AuthController.java
│   └── UserController.java
│
├── dto/
│   ├── LoginRequest.java
│   ├── RegisterRequest.java
│   └── AuthResponse.java
│
├── entity/
│   ├── User.java
│   └── Role.java
│
├── repository/
│   ├── UserRepository.java
│   └── RoleRepository.java
│
├── security/
│   ├── JwtUtil.java
│   ├── JwtFilter.java
│   └── SecurityConfig.java
│
├── service/
│   ├── AuthService.java
│   └── UserService.java
│
├── exception/
│   ├── GlobalExceptionHandler.java
│   └── CustomException.java
│
├── AuthSystemApplication.java
└── application.properties

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🔐 API Endpoints

✅ Register User

POST /api/auth/register

Request Body

{
  "username": "priyanka",
  "password": "1234",
  "email": "priyanka@gmail.com"
}

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✅ Login User

POST /api/auth/login

Request Body

{
  "username": "priyanka",
  "password": "1234"
}

Response

{
  "token": "eyJhbGciOiJIUzI1NiJ9..."
}

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🔒 Access Secured API

GET /api/users/profile

Header

Authorization: Bearer <JWT_TOKEN>

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🔑 JWT Authentication Flow

1. User logs in with username & password
2. Server validates credentials
3. JWT token is generated
4. Client sends token in Authorization header
5. JwtFilter validates token for every request
6. Access granted to secured endpoints

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⚙️ Configuration

Create application.properties file:

server.port=8080

spring.datasource.url=jdbc:mysql://localhost:3306/auth_db
spring.datasource.username=root
spring.datasource.password=your_password

spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true

jwt.secret=your_jwt_secret
jwt.expiration=86400000

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## 🧪 Testing

* Use **Postman**
* Register → Login → Copy JWT
* Pass JWT in `Authorization` header to access protected APIs

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## 🎯 Interview Explanation (One-Liner)

> “I built a Spring Boot authentication system using JWT and Spring Security, implementing secure login, registration, role-based authorization, and clean layered architecture.”

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## 📌 Future Enhancements

* Refresh Token
* OAuth2 / Google Login
* Email Verification
* Forgot Password Feature
* Docker Deployment

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## 👩‍💻 Author

**Priyanka Rode**
Java | Spring Boot | Backend Developer

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