Building a Web Server with Go: A Step-by-Step Guide
Getting Started with Go
Go, also known as Golang, is a great language for creating simple yet efficient web servers and web services. Its built-in HTTP package provides utilities for quickly creating a web or file server. In this tutorial, we’ll explore how to build your first web server with Go.
Setup
To follow this tutorial, you’ll need Go version 1.11 or higher. Let’s create the necessary files and establish the correct file structure. Create a server.go file and a static folder, which will contain two HTML files: index.html and form.html.
Importing Packages
Open the server.go file and import the required packages. We’ll use fmt to print useful data to the terminal and log to print fatal errors in case the web server crashes. The net/http package provides all the functionality for creating an HTTP client or server implementation.
Starting a Web Server with GET Routes
Let’s modify the code in our main() function to start a web server at port 8080. We’ll use the ListenAndServe method to start the web server and specify the port to listen for incoming requests.
Adding Handlers to the Web Server
We need to pass handlers to the server so it knows how to respond to incoming requests. We’ll use the HandleFunc function to add route handlers to the web server. Let’s create a handler function that responds to GET requests and returns a “Hello!” message.
Adding Basic Security to Routes
Security is crucial for any web server. Let’s explore some basic strategies to enhance the security of our Go web server. We’ll create a helloHandler function that checks whether the requested path is correct and whether the request method is GET.
Starting a Static Web Server
Let’s create a simple file server to host static files. We’ll modify the index.html file in the static folder and add a heading that says “Static Website.” To serve the static folder, we’ll add two lines of code to server.go.
Accepting a Form Submission POST Request
Finally, our web server needs to respond to a form submission. Let’s add some content to the form.html file in the static folder and create a handler function to accept the /form request.
Trying Out the Form Handler
Let’s test the form by starting the server with go run server.go. When the server starts, visit http://localhost:8080/form.html. Fill out the form and hit the submit button. The server should process your POST request and show you the result on the http://localhost:8080/form response page.
Congratulations!
You’ve successfully created your first Golang web and file server. If you want to explore Golang web servers further, the Golang HTTP package documentation is full of great examples. This tutorial on writing web apps in Go is another great resource that covers most of the basics.