Overview
API Gateway explores how a single edge service can keep client applications independent from a growing set of backend services. It accepts each request, verifies identity and policy, then forwards the request to the correct internal service through a stable public contract.
Request flow
Routes are defined around product capabilities instead of deployment details. Authentication and request validation happen before forwarding, while correlation IDs and consistent error responses make failures easier to trace across service boundaries.
Redis-backed rate limits protect expensive routes without adding state to each application instance. Health checks and timeouts keep an unavailable dependency from holding open every incoming request.
Design priorities
The project focuses on predictable contracts, small policy layers, and useful observability. The gateway does not absorb domain logic; services remain responsible for their own business rules and data.
Technology
The implementation is modeled with Java and Spring Boot, Redis for shared limits and short-lived state, and Docker for a repeatable local environment.