🌟 Building a Dynamic, Secure Proxy Gateway with Spring Boot 3.4 + Java 17

In today’s multi-vendor, multi-service environments, connecting different backend services securely and flexibly is no small challenge.

That’s why I’m excited to share my open-source project: 👉 Banking Proxy Gateway (GitHub)

🚀 What Is It?

This project is a dynamic, database-configured proxy gateway built with: ✅ Spring Boot 3.4 ✅ Java 17 ✅ JWT-based authentication ✅ RestTemplate-driven routing

It allows external clients (vendors) to:

• Securely access backend services using client-specific JWT tokens
• Dynamically configure backend endpoints via database records (no code changes needed)
• Set per-service timeouts for more control over third-party integrations

💡 Why Did I Build This?

In fintech and other industries, you often need to: ✅ Onboard new vendor connections without redeploying your app ✅ Securely route traffic to multiple backend APIs, each with their own credentials and limits ✅ Centralize logging, error handling, and security

Many teams end up hardcoding URLs or writing brittle gateway layers. I wanted a solution that’s: ✔ Database-driven ✔ Scalable ✔ Easy to extend

🏗️ How Does It Work?

The gateway exposes a unified endpoint:

POST /gateway/v1/{service}/**
Authorization: Bearer <JWT_TOKEN>
        

When a request comes in, the gateway: 1️⃣ Validates the token against the vendor’s clientId and clientSecret 2️⃣ Checks if the vendor has an active route for {service} 3️⃣ Proxies the request to the backend using RestTemplate, honoring custom timeouts

🔌 Example Setup

1️⃣ Add a Vendor

INSERT INTO vendors (client_id, client_secret, is_active)
VALUES ('vendor1', 'supersecret', true);
        

2️⃣ Add a Service Route

INSERT INTO service_routes (vendor_id, service_key, service_url, connect_timeout, read_timeout, is_active)
VALUES (1, 'orders', 'https://api.vendor1.com/orders', 10000, 15000, true);
        

3️⃣ Send a Proxy Request

curl -X POST \
  -H "Authorization: Bearer <your_vendor_jwt_token>" \
  -H "Content-Type: application/json" \
  -d '{"orderId":12345}' \
  http://your-gateway.com/gateway/v1/orders/process
        

🛡️ Key Features

✅ Dynamic routing → Add, remove, or update services through database configuration

✅ Per-vendor security → Each vendor has unique clientId + secret + JWT access

✅ Per-service timeouts → Handle slow or sensitive integrations gracefully

✅ Detailed error handling → Consistent error responses, even for backend failures

✅ Easy local development → Spring Boot + Maven setup, ready to run

⚙️ Tech Stack

• Spring Boot 3.4
• Java 17
• Spring Security (JWT)
• RestTemplate
• H2 / MySQL / PostgreSQL (your choice)

🔑 Extending the Project

✅ Add more vendors → insert into vendors table ✅ Add new services → insert into service_routes table ✅ Customize security → extend Spring Security for OAuth, IP filtering, etc. ✅ Improve performance → upgrade to WebFlux for non-blocking proxying

🌍 Future Plans

🛠 Vendor-specific rate limiting 📊 Per-route metrics and logging 🛡 Enhanced admin dashboard ⚡ WebFlux upgrade for reactive proxying ☁ Distributed caching for RestTemplate instances

🙌 Get Involved

I built this project to share with the open-source community and help others solve real-world integration problems.

👉 Check it out on GitHub: https://github.com/QaisarAbbasPK/BankingProxyGateway-Spring-Boot

Feel free to: ✅ Fork the repo ✅ Open issues or suggestions ✅ Submit pull requests ✅ Share your feedback!

Let’s make backend integrations simpler, more secure, and more powerful together.

💬 What do you think? Have you faced similar challenges integrating multiple services or vendors? Drop a comment or DM me — I’d love to hear your thoughts!

#SpringBoot #Java17 #OpenSource #Microservices #Gateway #Fintech #SpringSecurity #JWT #SoftwareEngineering #Integration

If you want, I can also help design a LinkedIn banner image or slide visuals to go with this article — just let me know! 🚀