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)

Mapping Between Boundaries

In the previous chapters, we discussed the web, application, domain, and persistence layers and what each of those layers contributes to implementing a use case.

We have, however, barely touched upon the dreaded and omnipresent topic of mapping between the models of each layer. I bet you have had a discussion at some point about whether to use the same model in two layers in order to avoid implementing a mapper.

The argument might have gone something like this:

Pro-Mapping Developer:

If we don't map between layers, we have to use the same model in both layers, which means that the layers will be tightly coupled.

Contra-Mapping Developer:

But if we do map between layers, we produce a lot of boilerplate code, which is overkill for many use cases, since they're only doing CRUD and have the same model across layers anyway.

As is often the case in discussions like this, there's truth to both sides of the argument. Let's...