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

15. HTTP Servers

Activity 15.01: Adding a Page Counter to an HTML Page

Solution:

  1. First, we import the necessary packages:
    package main
    import (
    "fmt"
    "log"
    "net/http"
    )
  2. Here, "net/http" is the usual package for http communication, "log" is the package for logging (in this case to the standard output), and "fmt" is the package used to format input and output. This can be used to send messages to the standard output, but we use it here just as a message formatter.
  3. We define here a type called PageWithCounter, which represents our handler, can count visits, and has a heading and some content for the page. The counter will increase every time the page loads:
    type PageWithCounter struct{
    counter int
    heading string
    content string
    }
    func(h *PageWithCounter) ServeHTTP(w http.ResponseWriter, r *http.Request)   {

    This is the standard handler function for any struct implementing the http.Handler interface. Note...