Mihalis Tsoukalos - Mastering Go: Harness the power of Go to build professional utilities and concurrent servers and services, 3rd Edition

The book you are reading right now is Mastering Go, Third Edition, which is all about helping you become a better Go developer! If you have the second edition of Mastering Go, do not throw it awayGo has not changed that much, and the second edition is still useful. However, Mastering Go, Third Edition is better than the second edition in many aspects.

There exist many exciting new topics in this edition, including writing RESTful services, working with the WebSocket protocol, and using GitHub Actions and GitLab Actions for Go projects, as well as an entirely new chapter on generics and the development of lots of practical utilities. Additionally, I tried to make this book smaller than the second edition and structure it in a more natural way to make it both easier and faster to read, especially if you are a busy professional.

I also tried to include the right amount of theory and hands-on contentbut, only you, the reader, can tell whether I succeed! Try to do the exercises located at the end of each chapter and do not hesitate to contact me about ways or ideas that can make future editions of this book even better!

This book is for intermediate Go programmers who want to take their Go knowledge to the next level. It will also be helpful for experienced developers in other programming languages who want to learn Go without going over programming basics.

Chapter 1, A Quick Introduction to Go, begins by talking about the history of Go, the important characteristics of Go, and the advantages of Go, before describing the godoc and go doc utilities and explaining how we can compile and execute Go programs. Afterward, the chapter talks about printing output and getting user input, working with command-line arguments, and using log files. Lastly, we develop a basic version of a phone book application that we are going to keep improving in forthcoming chapters.

Chapter 2, Basic Go Data Types, discusses the basic data types of Go, both numeric and non-numeric, as well as arrays and slices that allow you to group data of the same data type. It also considers Go pointers, constants, and working with dates and times. The last part of the chapter is about generating random numbers and populating the phone book application with random data.

Chapter 3, Composite Data Types, begins with maps, before going into structures and the struct keyword. Additionally, it talks about regular expressions, pattern matching, and working with CSV files. Lastly, we improve the phone book application by adding data persistency to it.

Chapter 4, Reflection and Interfaces, is about reflection, interfaces and type methods, which are functions attached to data types. The chapter also includes the use of the sort.Interface interface for sorting slices, the use of the empty interface, type assertions, type switches, and the error data type. Additionally, we discuss how Go can mimic some object-oriented concepts before improving the phone book application.

Chapter 5, Go Packages and Functions, is all about packages, modules, and functions, which are the main elements of packages. Among other things, we create a Go package for interacting with a PostgreSQL database, create documentation for it, and explain the use of the sometimes tricky defer keyword. This chapter also includes information about the use of GitLab Runners and GitHub Actions for automation and how to create a Docker image for a Go binary.

Chapter 6, Telling a UNIX System What to Do, is about systems programming, which includes subjects such as working with command-line arguments, handling UNIX signals, file input and output, the