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Sherif sani
Sherif sani

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A tiny Spring Boot 'profile' microservice — Stage‑0 HNG backend

#java #api #backend

I built a minimal Spring Boot service for my HNG Stage‑0 backend task that returns a profile object plus a fun cat fact. The goal was to deliver a clear, runnable microservice in a few files so reviewers can quickly run and inspect the code.

What it does

  • Exposes GET /me
  • Returns a JSON payload with status, a small user profile (name, role, links), a timestamp, and a cat fact fetched from https://catfact.ninja/fact

Architecture (short)

  • ProfileController — handles /me and returns a ProfileResponse DTO.
  • ProfileService — builds the profile and fetches the external cat fact using Java HttpClient.
  • Profile (domain) and ProfileResponse (DTO) — simple POJOs for shape and serialization.
  • Spring Boot entrypoint and a single minimal unit test to ensure application context loads.

Why this shape?

  • Minimal surface area: reviewers can audit the domain, controller, and service quickly.
  • External call isolated in the service so it’s easy to mock or replace.
  • Small codebase is ideal for early-stage tasks and focused feedback.

How to run locally

  • From the project root (uses the included Maven wrapper): 
./mvnw spring-boot:run
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What I learned / next steps

  • Keep services focused and small for fast review cycles.
  • Inject HttpClient (or a wrapper) to make the external API call testable and mockable.
  • Add structured error handling and logging for robustness.
  • Add unit tests that mock the cat-fact API and an integration test for the controller.

check the repository: here

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