Book Image

The Go Workshop

By : Delio D'Anna, Andrew Hayes, Sam Hennessy, Jeremy Leasor, Gobin Sougrakpam, Dániel Szabó
Book Image

The Go Workshop

By: Delio D'Anna, Andrew Hayes, Sam Hennessy, Jeremy Leasor, Gobin Sougrakpam, Dániel Szabó

Overview of this book

The Go Workshop will take the pain out of learning the Go programming language (also known as Golang). It is designed to teach you to be productive in building real-world software. Presented in an engaging, hands-on way, this book focuses on the features of Go that are used by professionals in their everyday work. Each concept is broken down, clearly explained, and followed up with activities to test your knowledge and build your practical skills. Your first steps will involve mastering Go syntax, working with variables and operators, and using core and complex types to hold data. Moving ahead, you will build your understanding of programming logic and implement Go algorithms to construct useful functions. As you progress, you'll discover how to handle errors, debug code to troubleshoot your applications, and implement polymorphism using interfaces. The later chapters will then teach you how to manage files, connect to a database, work with HTTP servers and REST APIs, and make use of concurrent programming. Throughout this Workshop, you'll work on a series of mini projects, including a shopping cart, a loan calculator, a working hours tracker, a web page counter, a code checker, and a user authentication system. By the end of this book, you'll have the knowledge and confidence to tackle your own ambitious projects with Go.
Table of Contents (21 chapters)
Free Chapter
1
1. Variables and Operators
2
2. Logic and Loops

Go Context Package

We've seen how to run concurrent code and run it until it has finished, waiting for the completion of some processing through WaitGroup or channel reads. You might have seen in some Go code, especially code related to HTTP calls, some parameters from the context package, and you might have wondered what it is and why it is used. All the code we've written here is running in our machines and does not pass through the internet, so we hardly have any delay due to latency; however, in situations involving HTTP calls, we might encounter servers that do not respond and get stuck. In such cases, how do we stop our call if the server does not respond after a while? How do we stop the execution of a routine that runs independently when an event occurs? Well, we have several ways, but a standard one is to use contexts, and we will see now how they work. A context is a variable that is passed through a series of calls and might hold some values or may be empty. It...