Auth API 🔐

REST API built with Spring Boot that implements JWT authentication and role-based access control.

Tech Stack

Java 21 · Spring Boot 3.x · Maven · Docker · Spring Security · jjwt

Getting Started

Option 1: Docker (recommended) 🐳

Build the image:

docker build -t auth-api .

Run the container:

docker run -p 8080:8080 \
  -e JWT_SECRET=your-secret-key-min-32-characters \
  -e ADMIN_MAIL=admin@example.com \
  -e ADMIN_PASSWORD=your-admin-password \
  auth-api

Option 2: Local 💻

Requirements: Java 21, Maven

1. Clone the repository
2. Set the required environment variables (see Configuration)
3. Run the application:

./mvnw spring-boot:run

Configuration ⚙️

The following environment variables are required:

Variable	Description	Example
JWT_SECRET	Secret key for JWT signing (min. 32 characters)	my-super-secret-key-32-chars!!
ADMIN_MAIL	Email for the default admin user	admin@example.com
ADMIN_PASSWORD	Password for the default admin user	admin123

You can check application.properties.example for reference.

Endpoints 🛣️

Auth (public)

Method	Endpoint	Description	Body
POST	/api/auth/register	Register a new user	{ "email": "", "password": "" }
POST	/api/auth/login	Login and get JWT token	{ "email": "", "password": "" }

Both endpoints return:

{
  "token": "eyJhbGci..."
}

Demo (protected) 🔒

Include the token in the Authorization header: Bearer <token>

Method	Endpoint	Role required	Description
GET	/api/demo	USER, ADMIN	Returns a demo message
GET	/api/demo/admin	ADMIN only	Returns an admin-only message

Common Issues 🚨

WeakKeyException on startup Your JWT_SECRET is too short. It must be at least 32 characters.

401 Unauthorized on protected endpoints Make sure you are sending the token in the Authorization header with the format Bearer <token>.

Port already in use Another process is using port 8080. Stop it or change the port with -p 9090:8080 in the Docker run command.