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
Customer Feedback

Using it all - concurrent singleton

Now that we know how to create Goroutines and channels, we'll put all our knowledge in a single package. Think back to the first few chapter, when we explained the singleton pattern-it was some structure or variable that could only exist once in our code. All access to this structure should be done using the pattern described, but, in fact, it wasn't concurrent safe.

Now we will write with concurrency in mind. We will write a concurrent counter, like the one we wrote in the mutexes section, but this time we will solve it with channels.

Unit test

To restrict concurrent access to the singleton instance, just one Goroutine will be able to access it. We'll access it using channels--the first one to add one, the second one to get the current count, and the third one to stop the Goroutine.

We will add one 10,000 times using 10,000 different Goroutines launched from two different singleton instances. Then, we'll introduce a loop to check the count of the singleton...