🛡️ Product Service API

A production-ready REST API built with Spring Boot 3 featuring JWT authentication, role-based access control, and full security hardening.

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🚀 Tech Stack

Layer	Technology
Language	Java 21
Framework	Spring Boot 3.3
Security	Spring Security + JWT (jjwt 0.12)
Database	PostgreSQL (prod) / H2 (dev)
Build Tool	Maven
Containerization	Docker

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✨ Features

• ✅ JWT Authentication (login → token → access)
• ✅ Role-based access control (ROLE_ADMIN, ROLE_USER)
• ✅ Global exception handling with consistent error responses
• ✅ Input validation on all request bodies
• ✅ Structured logging (JSON in prod, readable in dev)
• ✅ Dev / Prod profile separation
• ✅ Health check endpoint via Spring Actuator
• ✅ Dockerized for easy deployment

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📁 Project Structure

src/
├── main/java/com/example/
│   ├── auth/               # Login endpoint
│   ├── exception/          # Global error handler
│   ├── security/           # JWT filter, service, config
│   └── user/               # User entity, repository, service
├── main/resources/
│   ├── application-dev.properties
│   └── application-prod.properties
└── test/
    ├── auth/               # Integration tests
    └── security/           # JWT unit tests

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⚙️ Getting Started

Prerequisites

• Java 21+
• Maven 3.8+
• PostgreSQL (for prod) or just run dev profile with H2

1. Clone the repo

git clone https://github.com/YOUR_USERNAME/product-service.git
cd product-service

2. Run in dev mode (H2 in-memory DB)

./mvnw spring-boot:run -Dspring-boot.run.profiles=dev

App starts at: http://localhost:8080

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🔐 Authentication Flow

POST /auth/login  →  returns JWT token
GET  /products    →  requires Bearer token

Step 1 — Login

curl -X POST http://localhost:8080/auth/login \
  -H "Content-Type: application/json" \
  -d '{"username":"admin","password":"admin123"}'

Response:

{
  "accessToken": "eyJhbGciOiJIUzI1NiJ9...",
  "tokenType": "Bearer"
}

Step 2 — Use the token

curl http://localhost:8080/products \
  -H "Authorization: Bearer YOUR_TOKEN_HERE"

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👥 Default Users (dev only)

Username	Password	Role
admin	admin123	ADMIN + USER
user	user123	USER

⚠️ These are seeded automatically in dev profile only. Never use in production.

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🌍 API Endpoints

Method	Endpoint	Access	Description
POST	/auth/login	Public	Get JWT token
GET	/products	USER, ADMIN	List all products
POST	/products	ADMIN only	Create product
PUT	/products/{id}	ADMIN only	Update product
DELETE	/products/{id}	ADMIN only	Delete product
GET	/actuator/health	Public	Health check

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🐳 Docker

# Build image
docker build -t product-service .

# Run with environment variables
docker run -p 8080:8080 \
  -e SPRING_PROFILES_ACTIVE=prod \
  -e SPRING_DATASOURCE_URL=jdbc:postgresql://host:5432/mydb \
  -e SPRING_DATASOURCE_USERNAME=postgres \
  -e SPRING_DATASOURCE_PASSWORD=yourpassword \
  -e JWT_SECRET=your_base64_secret \
  product-service

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🔒 Environment Variables (Production)

Variable	Description
SPRING_DATASOURCE_URL	PostgreSQL connection URL
SPRING_DATASOURCE_USERNAME	DB username
SPRING_DATASOURCE_PASSWORD	DB password
JWT_SECRET	Base64-encoded secret (min 64 bytes)

Generate a secure JWT secret:

openssl rand -base64 64

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🧪 Running Tests

./mvnw test

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📄 License

MIT License — free to use and modify.