Make Your Own Web Server with Go: A Quick Guide

The Go programming language is well-known for having a built-in web server. In this article you will learn how you can easily make your own web server with Go. You won’t need any other packages beside the ones that are already built in!

First, hop in to your text editor. Then create a file called webserver.go and enter the following code:

package main

import (
  "net/http"
  "io"
)

func main() {
  http.HandleFunc("/", servePage)
	http.ListenAndServe(":8080", nil)
}

func servePage(writer http.ResponseWriter, reqest *http.Request) {
  io.WriteString(writer, "Hello world!")
}

Let’s break down the block of code above. We import the net/http package: this package contains the web server itself. Then we also import the io package, we will make use of this later to actually serve something to the client.

In the main function we do two things. First of all we instruct the server to let the function called servePage handle all incoming traffic to / - in this case it means that it handles requests to any URL.

The second thing we do is actually activating the server. We do this using a function named ListenAndServe. This function requires two parameters: the port (as string), in this case it’s 8080, and the handler (as Handler) - however the last one isn’t important yet. We will just make it nil and everything will work just fine.

In the servePage we do just one simple thing, for now. Using the io package and the WriteString function that it contains we can respond to the clients’ request with the text Hello world! (or any other string, of course).

You also might have noticed that the servePage function has two arguments: the writer and the request. With the writer you can actually respond to a HTTP request and with the request you may get more information about the request itself.

Congratulations! You just created your first web server! If you want to test it: just run go run webserver.go, fire up a browser and navigate to http://localhost:8080!