Testing

goninjatest (a separate module-level package, like openapi/docsui/id — only test code needs to import it) gets a resource from zero to a real HTTP request in a few lines: NewDB opens and AutoMigrates an in-memory SQLite database, NewServer mounts any number of resources on a fresh httptest.Server. Both clean up after themselves via t.Cleanup.

func TestBookResource_Create(t *testing.T) {
    db := goninjatest.NewDB(t, &models.Book{}, &models.Author{})
    srv := goninjatest.NewServer(t, api.NewBookResource(db))

    resp, err := http.Post(srv.URL+"/books", "application/json",
        strings.NewReader(`{"title":"Dune","author_id":"...","price":9.99}`))
    if err != nil || resp.StatusCode != http.StatusCreated {
        t.Fatalf("POST /books: err=%v status=%v", err, resp.StatusCode)
    }
}

No Postgres, no hand-rolled httptest.NewServer(mux) boilerplate, no gorm.Open call to remember the driver for — generated resource code has no Postgres-specific behavior, so the same in-memory SQLite connection exercises it end to end.