Book Image

Go Design Patterns

By : Mario Castro Contreras
Book Image

Go Design Patterns

By: Mario Castro Contreras

Overview of this book

Go is a multi-paradigm programming language that has built-in facilities to create concurrent applications. Design patterns allow developers to efficiently address common problems faced during developing applications. Go Design Patterns will provide readers with a reference point to software design patterns and CSP concurrency design patterns to help them build applications in a more idiomatic, robust, and convenient way in Go. The book starts with a brief introduction to Go programming essentials and quickly moves on to explain the idea behind the creation of design patterns and how they appeared in the 90’s as a common "language" between developers to solve common tasks in object-oriented programming languages. You will then learn how to apply the 23 Gang of Four (GoF) design patterns in Go and also learn about CSP concurrency patterns, the "killer feature" in Go that has helped Google develop software to maintain thousands of servers. With all of this the book will enable you to understand and apply design patterns in an idiomatic way that will produce concise, readable, and maintainable software.
Table of Contents (17 chapters)
Go Design Patterns
About the Author
About the Reviewer
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State design pattern

State patterns are directly related to FSMs. An FSM, in very simple terms, is something that has one or more states and travels between them to execute some behaviors. Let's see how the State pattern helps us to define FSM.


A light switch is a common example of an FSM. It has two states--on and off. One state can transit to the other and vice versa. The way that the State pattern works is similar. We have a State interface and an implementation of each state we want to achieve. There is also usually a context that holds cross-information between the states.

With FSM, we can achieve very complex behaviors by splitting their scope between states. This way we can model pipelines of execution based on any kind of inputs or create event-driven software that responds to particular events in specified ways.


The main objectives of the State pattern is to develop FSM are as follows:

  • To have a type that alters its own behavior when some internal things have changed...