Testing a Web Adapter with Integration Tests
Moving outward another layer, we arrive at our adapters. Let's discuss testing a web adapter.
Recall that a web adapter takes input, for example, in the form of JSON strings, via HTTP, maybe does some validation on it, maps the input to the format a use case expects, and then passes it to that use case. It then maps the result of the use case back to JSON and returns it to the client via an HTTP response.
In the test for a web adapter, we want to make certain that all those steps work as expected:
@WebMvcTest(controllers = SendMoneyController.class)
class SendMoneyControllerTest {
  @Autowired
  private MockMvc mockMvc;
  @MockBean
  private SendMoneyUseCase sendMoneyUseCase;
  @Test
  void testSendMoney() throws Exception {
    mockMvc.perform(
        post("/accounts/send/{sourceAccountId}/{targetAccountId}/{amount}",
 ...