Book Image

Get Your Hands Dirty on Clean Architecture

By : Tom Hombergs
Book Image

Get Your Hands Dirty on Clean Architecture

By: Tom Hombergs

Overview of this book

Building for maintainability is key to keeping development costs low and processes easy. The second edition of Get Your Hands Dirty on Clean Architecture is here to equip you with the essential skills and knowledge to build maintainable software. With this comprehensive guide, you’ll explore the drawbacks of conventional layered architecture and the advantages of domain-centric styles such as Robert C. Martin's Clean Architecture and Alistair Cockburn's Hexagonal Architecture. Then, you’ll dive into hands-on explanations on how to convert hexagonal architecture into actual code. You'll learn in detail about different mapping strategies between the layers of hexagonal architecture and discover how to assemble the architectural elements into an application. Additionally, you’ll understand how to enforce architecture boundaries, which shortcuts produce what types of technical debt, and how, sometimes, it is a good idea to willingly take on those debts. By the end of this second edition, you'll be armed with a deep understanding of the hexagonal architecture style and be ready to create maintainable web applications that save money and time.
Table of Contents (13 chapters)

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}",

 ...