Book Image

Hands-On Dependency Injection in Go

By : Corey Scott
Book Image

Hands-On Dependency Injection in Go

By: Corey Scott

Overview of this book

Hands-On Dependency Injection in Go takes you on a journey, teaching you about refactoring existing code to adopt dependency injection (DI) using various methods available in Go. Of the six methods introduced in this book, some are conventional, such as constructor or method injection, and some unconventional, such as just-in-time or config injection. Each method is explained in detail, focusing on their strengths and weaknesses, and is followed with a step-by-step example of how to apply it. With plenty of examples, you will learn how to leverage DI to transform code into something simple and flexible. You will also discover how to generate and leverage the dependency graph to spot and eliminate issues. Throughout the book, you will learn to leverage DI in combination with test stubs and mocks to test otherwise tricky or impossible scenarios. Hands-On Dependency Injection in Go takes a pragmatic approach and focuses heavily on the code, user experience, and how to achieve long-term benefits through incremental changes. By the end of this book, you will have produced clean code that’s easy to test.
Table of Contents (15 chapters)

Chapter 4, Introduction to the ACME Registration Service

1. Which of the goals defined for our service is most important to you personally?

This is subjective, and as such, there is no right answer. Personally, it would have to be readability or testability. If the code is easy to read, then I can figure it out easier and probably remember more about it as well. On the other hand, if it's more testable, then I can leverage that fact to write more tests. With more tests in place, I won't have to remember as much and can let the tests make sure everything performs as I need it.


2. Which of the issues outlined seems to be most urgent or important?

This is also subjective. It might surprise you, but I would say lack of isolation in tests. With the tests as they are, every test is somewhat akin to an end-to-end test. This means that the test setup is lengthy and when...