Enterprise-Ready RESTful API Core with JWT Auth

What problem was solved

Developed a secure, transaction-safe backend API that orchestrates user authentication, role-based permissions (for customers, providers, and admins), and service booking workflows. It resolves critical backend challenges around stateless session security (JWT + logout blacklist), database schema integrity (via versioned migrations), and API integration reliability (via Swagger UI documentation and extensive JUnit testing).

Note: Built to run seamlessly on a local H2 in-memory database for testing and development, or PostgreSQL for production.

Key Features

• Stateless JWT Authentication & Secure Password Hashing
• Session Invalidation via Token Blacklisting on Logout
• Role-Based Access Control (RBAC) for Admin, Provider, and Customer roles
• Transactional Booking Engine with Status Workflows (Accept/Reject/Cancel)
• Dispute Resolution and Booking Conflict Management System
• Multi-parameter Search and Filter endpoints for service listings
• Paginated News Feed and Notification Delivery systems
• Version-controlled Database Schema Migrations using Flyway
• Automated Unit and Integration Testing with Mockito and JUnit 5
• Containerized Multi-stage Build configurations using Docker & Docker Compose
• Interactive API Documentation and Testing Console via Swagger UI/OpenAPI

Project Outcome

Production-Ready Backend Engine: Delivered a highly secure, containerized RESTful API that handles user permissions, transactional bookings, and search filters with zero-downtime database migrations. High Performance & Security: Secured endpoint requests with custom JWT auth and a session blacklist system, keeping latency low through local in-memory caching and request rate-limiting. Fully Tested & Documented Codebase: Achieved robust system reliability via a comprehensive JUnit/Mockito automated test suite and provided an interactive API playground (Swagger UI) for seamless client integration.

Challenges

Stateless Session Invalidation: Overcoming the limitation of stateless JWTs by designing a custom token blacklist system to support secure user logouts. Transactional State Safety: Mitigating race conditions and maintaining database consistency across multi-step booking states (e.g., booking approvals, rejections, and disputes). Database Migration Alignment: Managing incremental database schema changes and relationships (FK constraints) across development and production environments using version-controlled Flyway scripts.

Project Media

Team members