Book Image

Get Your Hands Dirty on Clean Architecture - Second Edition

By : Tom Hombergs
4 (1)
Book Image

Get Your Hands Dirty on Clean Architecture - Second Edition

4 (1)
By: Tom Hombergs

Overview of this book

Building for maintainability is key to keep development costs low (and developers happy). 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. Building upon the success of the first edition, this comprehensive guide explores the drawbacks of conventional layered architecture and highlights the advantages of domain-centric styles such as Robert C. Martin's Clean Architecture and Alistair Cockburn's Hexagonal Architecture. Then, the book dives into hands-on chapters that show you how to manifest a Hexagonal Architecture in actual code. You'll learn in detail about different mapping strategies between the layers of a Hexagonal Architecture and see how to assemble the architecture elements into an application. The later chapters demonstrate how to enforce architecture boundaries, what 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. Whether you're a seasoned developer or a newcomer to the field, "Get Your Hands Dirty on Clean Architecture" will empower you to take your software architecture skills to new heights and build applications that stand the test of time.
Table of Contents (18 chapters)

Slicing port interfaces

One question that comes to mind when implementing services is how to slice the port interfaces that define the database operations available to the application core.

It’s a common practice to create a single repository interface that provides all database operations for a certain entity, as outlined in Figure 7.2.

Figure 7.2 – Centralizing all database operations into a single outgoing port interface makes all services depend on methods they don’t need

Figure 7.2 – Centralizing all database operations into a single outgoing port interface makes all services depend on methods they don’t need

Each service that relies on database operations will then have a dependency on this single “broad” port interface, even if it uses only a single method from the interface. This means we have unnecessary dependencies in our code base.

Dependencies on methods that we don’t need in our context make the code harder to understand and test. Imagine that we’re writing a unit test for RegisterAccountService from the preceding figure....