Book Image

Domain-Driven Design with Golang

By : Matthew Boyle
4 (2)
Book Image

Domain-Driven Design with Golang

4 (2)
By: Matthew Boyle

Overview of this book

Domain-driven design (DDD) is one of the most sought-after skills in the industry. This book provides you with step-by-step explanations of essential concepts and practical examples that will see you introducing DDD in your Go projects in no time. Domain-Driven Design with Golang starts by helping you gain a basic understanding of DDD, and then covers all the important patterns, such as bounded context, ubiquitous language, and aggregates. The latter half of the book deals with the real-world implementation of DDD patterns and teaches you how to build two systems while applying DDD principles, which will be a valuable addition to your portfolio. Finally, you’ll find out how to build a microservice, along with learning how DDD-based microservices can be part of a greater distributed system. Although the focus of this book is Golang, by the end of this book you’ll be able to confidently use DDD patterns outside of Go and apply them to other languages and even distributed systems.
Table of Contents (13 chapters)
Part 1: Introduction to Domain-Driven Design
Part 2: Real -World Domain-Driven Design with Golang

Working with entities

In domain-driven design, entities are defined by their identity. Their attributes do not define them, and it is expected that although their attributes may change over time, their identity will not. While the entity may change so much that it is indistinguishable from where it started, it retains the same identity, and we treat it as the same object. Let’s look at an example. On, you can sign up as a user. If you choose to sell something, you become a seller. You can also choose to bid on items. A naïve model of this might look as follows:

Figure 3.1 – A simple domain model for an auction site

Some actions that could take place in our system are as follows:

  • A user updates their address
  • A user updates their email address
  • An auction end time is updated

These actions do not change the identity of our entity. We are still referencing the same ID, but some attributes may have changed.