Golang : Generate 403 Forbidden to protect a page or prevent indexing by search engine

Got a question from a Golang newbie. He is asking how to protect certain directory or page from being accessed by the public or getting indexed by search engine.

Since he is using the Go internal web server instead of the Apache and Nginx, therefore, the .htaccess method will not work.

 # disable directory browsing
 Options -Indexes

To prevent a page from being accessed, the web server needs to reply with HTTP/1.1 403 Forbidden status code. Here is the code to do just that. Example adapted from my previous tutorial on how to return HTTP status codes in Golang.

 package main

 import (
 "net/http"
 )

 func returnCode403(w http.ResponseWriter, r *http.Request) {
 // see http://golang.org/pkg/net/http/#pkg-constants
 w.WriteHeader(http.StatusForbidden)
 w.Write([]byte("403 HTTP status code returned!"))
 }

 func main() {
 mux := http.NewServeMux()
 mux.HandleFunc("/", returnCode403)

 http.ListenAndServe(":8080", mux)
 }

Executing curl -I localhost:8080 will give you :

 HTTP/1.1 403 Forbidden
 Date: Wed, 21 Oct 2015 03:12:36 GMT
 Content-Length: 30
 Content-Type: text/plain; charset=utf-8

Reference :

https://www.socketloop.com/tutorials/golang-how-to-return-http-status-code