copilot-cli-springboot-jwt

A secure, production-ready Spring Boot REST API featuring JWT authentication and a layered architecture, with PostgreSQL support for production use. Built entirely using GitHub Copilot CLI as the primary development and debugging assistant—from initial scaffolding through security implementation to systematic troubleshooting of Spring Security configurations.

🤖 Built with GitHub Copilot CLI

GitHub Copilot CLI served as the primary development assistant throughout the entire lifecycle of this project. It generated the complete layered architecture with controller, service, repository, entity, and DTO layers following Spring Boot best practices. The CLI implemented JWT security with custom filter chains, handled Spring Security configuration challenges, and provided systematic debugging support when authentication endpoints encountered issues. All code adheres to industry standards, with proper separation of concerns, bean validation, and exception handling generated through iterative prompts and refinements.

Key Features

• JWT Authentication - Stateless token-based auth with HS512 signing and BCrypt password hashing
• RESTful API - Clean endpoints with proper HTTP semantics and validation
• Layered Architecture - Controller, service, repository, entity, and DTO separation
• Spring Security - Custom JWT filter chain with role-based access control
• Multi-Database Support - PostgreSQL for production, H2 for development
• Global Exception Handling - Consistent error responses across all endpoints
• Bean Validation - Input validation with custom error messages

Technologies

• Spring Boot 3.2.0
• Spring Security with JWT (jjwt 0.12.3)
• Spring Data JPA
• PostgreSQL / H2
• Maven
• Java 17

Running Locally

Prerequisites: Java 17 or higher

Quick Start:

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

The application starts at http://localhost:8081 with H2 console at /h2-console.

Endpoints:

• POST /api/auth/register - Create new user
• POST /api/auth/login - Authenticate and receive JWT token
• GET /api/tasks - Access protected resources (requires JWT)

Authentication (Postman)

Register a User

• Method: POST
• URL: http://localhost:8080/api/auth/register
• Headers:
  • Content-Type: application/json
• Body (raw → JSON):

Authentication (Postman)

Register a User

• Method: POST
• URL: http://localhost:8080/api/auth/register
• Headers:
  • Content-Type: application/json
• Body (raw → JSON):

{
  "username": "testuser",
  "email": "testuser@example.com",
  "password": "password123"
}

For PostgreSQL setup, see application.properties configuration.

Copilot CLI Documentation

Comprehensive documentation on how GitHub Copilot CLI was used throughout development:

• COPILOT_WORKFLOW.md - Complete development journey from initial prompt to deployment-ready code, including generation process, iterative refinement, and productivity analysis
• COPILOT_DEBUGGING.md - Real debugging sessions with systematic troubleshooting of Spring Security 403 errors and environment-specific adaptations
• ARCHITECTURE.md - Deep dive into layered architecture, JWT authentication flow, security configurations, and design patterns

📊 Productivity Metrics

Task	Without Copilot	With Copilot	Time Saved
Project setup	45 min	5 min	89%
Entity/Repository	30 min	10 min	67%
JWT implementation	90 min	15 min	83%
Security config	60 min	15 min	75%
Service/Controller	60 min	20 min	67%
Debugging 403 error	120 min	20 min	83%
Testing setup	45 min	20 min	56%
Documentation	60 min	15 min	75%
Total	8.5 hours	2 hours	76%

License

MIT