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)

Reviewing Our Progress

In this, our final chapter, we will take a look back and compare the state and quality of our sample service now, after applying dependency injection (DI), with how it was when we started.

We will be taking a look at the improvements we have made, along with one final look at our dependency graph, and will discuss our improvements in test coverage and the testability of the service.

Finally, we will wrap up this chapter with a brief discussion of what we could have done if we had been starting a new service with DI instead of applying it to existing code.

The following topics will be covered in this chapter:

  • An overview of the improvements
  • A review of the dependency graph
  • A review of test coverage and testability
  • Starting a new service with DI