Testing Web API endpoints (unit / integration)?

Short answer: Unit testing: Mock services/repositories using Moq or FakeItEasy. Integration testing: Use WebApplicationFactory<T> + TestServer + HttpClient. var client = _factory.CreateClient();

Example code

var response = await client.GetAsync("/api/products");

Real-world example (ShopNest)

A ShopNest checkout request flows through middleware, hits a minimal API or controller, uses scoped services, and returns ProblemDetails on errors.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.