Golang : Get final or effective URL with Request.URL example

There are times when we query a web server, it will re-direct internally and returns back with a slightly different URL structure. The returned URL is known as final URL or "effective url". In this following example, we will learn how to use https://golang.org/pkg/net/http/#Request.URL to retrieve the final URL.

 package main

 import (
 "fmt"
 "net/http"
 )

 func main() {

 // without https (SSL)
 originalURL := "http://socketloop.com"

 resp, err := http.Get(originalURL)

 if err != nil {
 fmt.Println(err)
 }

 // if there is any re-direction happening behind the scene
 // the finalURL will be different
 // in this case, there will be a re-direction to https (SSL) version

 finalURL := resp.Request.URL.String()

 fmt.Println("Original URL is : ", originalURL)
 fmt.Println("Final URL is : ", finalURL)
 }

Socketloop.com's NGINX web server will automatically redirect all non-https request to https(SSL). Therefore, the final URL will be SSL-ed connection.

Original URL is : http://socketloop.com

Final URL is : https://socketloop.com/

References :

https://www.socketloop.com/tutorials/golang-http-get-example

http://curl.haxx.se/mail/lib-2008-07/0209.html