Introduction

Go (Golang) is a versatile language that can be used for web development. In this guide, we'll walk you through the process of writing a basic web application in Go, including creating routes, handling requests, and rendering HTML templates. You'll learn the key concepts and be provided with sample code to get started.


Creating a Web Server

To create a web application in Go, you start by creating a web server. This server listens on a port and handles incoming HTTP requests. Here's an example of creating a simple web server:

package main
import (
    "fmt"
    "net/http"
)
func handler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "Hello, Go Web Application!")
}
func main() {
    http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)
}

In this code, we create an HTTP server that listens on port 8080 and responds with "Hello, Go Web Application!" to all incoming requests.


Routing and Handling Requests

In a web application, routing is essential for directing requests to the appropriate handlers. You can define routes and handle different HTTP methods. Here's an example of handling a specific route:

package main
import (
    "fmt"
    "net/http"
)
func helloHandler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintln(w, "Hello, Web Application!")
}
func main() {
    http.HandleFunc("/hello", helloHandler)
    http.ListenAndServe(":8080", nil)
}

In this code, we define a route at "/hello" and respond with "Hello, Web Application!" when that route is accessed.


Rendering HTML Templates

A basic web application often involves rendering HTML templates to display dynamic content. You can use the "html/template" package to achieve this. Here's an example of rendering a simple HTML template:

package main
import (
    "fmt"
    "html/template"
    "net/http"
    "os"
)
func helloHandler(w http.ResponseWriter, r *http.Request) {
    t, _ := template.New("webpage").Parse("<html><body><h1>Hello, {{.}}!</h1></body></html>")
    t.Execute(w, "Web Application")
}
func main() {
    http.HandleFunc("/hello", helloHandler)
    http.ListenAndServe(":8080", nil)
}

In this code, we create an HTML template and use it to render a dynamic "Hello, Web Application!" message in the response.


Further Resources

To continue learning about writing web applications in Go, consider these resources: