Preface

Welcome to the book Go Design Patterns! With this book, you'll learn basic and advanced techniques and patterns with the Go language. Don't worry if you have never written Go code before; this book will gradually introduce you to the various concepts in Go programming. At the same time, experts will find many tips and tricks on the language, so I encourage you to not miss any chapter. If you already know the classic design patterns, you'll find this book very handy, not only as a reference book but also as a way to learn idiomatic Go approaches to solve common problems that you may already know.

The book is divided in three sections:

• Introduction to the Go language: This is the first part of the book, where you'll learn the basic syntax, the tools that comes with the binary distributions, basic testing, JSON parsing, and more. We leave concurrency for a later chapter to focus on the way that the syntax and the compiler work in a typical Go app.
• Classic design patterns in idiomatic Go: The second section presents the classic design patterns but as we will see, they are quite different, partly because of the lack of inheritance in Go, but also because we have different and more optimal ways to solve the same problems. A newcomer to the language will find the examples in this section very useful as a way to understand the roots of Go and the idiomatic ways in which you can solve problems using Go in the same manner as you would solve in languages such as Java or C++. Most examples are presented by using TDD and some of them even show examples within Go standard library that uses these patterns.
• Concurrency patterns: The focus in this section is learning about concurrent structures and parallel execution. You will learn most of the primitives in Go to write concurrent apps, and we will develop some of the classical design patterns with concurrent structures to maximize parallelism. Also, we will learn some of the typical structures to develop concurrent apps in Go. You learn how a classical pattern can become more complex if we need it to work in a concurrent way but the idea is to understand Go concurrent primitives so that the reader finishes the book knowing how to write their own concurrent design patterns by using the knowledge taken from the book.

The book will slowly raise the difficulty of some tasks. We have explained tips and tricks in every chapter.