How we write Go API integration tests using Uber's fxtest package

We recently made a push to increase our API test coverage. We’re a Go shop here at Nuon , and use the Gin web framework along with GORM for our APIs, and Temporal to execute workflows. While we had a good number of unit tests, we felt we really needed integration tests. We wanted these tests to exercise our API endpoints and also verify the data was saved correctly while still mocking out calls to other systems, like Temporal. If an API creates a Temporal workflow, we wanted a separate test to verify the workflow logic was correct on the other end. Fx makes it easy for us to manage our app dependencies and decouple these tests. What Is Fx? Fx is a dependency injection (DI) framework for Go, developed at Uber. At its core, it simplifies the problem of wiring dependencies together. Instead of manually constructing and passing dependencies through every layer of your application, you map types to constructors. When something depends on a type, Fx figures out how to provide it and injects