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)

Slicing Controllers

In most web frameworks – such as Spring MVC in the Java world – we create controller classes, which perform the responsibilities we have discussed previously. So, do we build a single controller that answers all the requests directed at our application? We don't have to. A web adapter can certainly consist of more than one class.

We should take care, however, to put these classes into the same package hierarchy to mark them as belonging together, as discussed in Chapter 3, Organizing Code.

So, how many controllers do we build? I say we should build too many rather than too few. We should make sure that each controller implements a slice of the web adapter that is as narrow as possible and that shares as little as possible with other controllers.

Let's take the operations on an account entity within our BuckPal application. A popular approach is to create a single AccountController that accepts requests for all operations that relate to accounts. A...