Golang : Set or add headers for many or different handlers

Problem :

In Golang, setting headers can be done easily with the Set() method.

At the moment, you are setting headers for each individual handler in such as manner :

 func handlerA(w http.ResponseWriter, req *http.Request) {
 w.Header().Set("X-Frame-Options", "SAMEORIGIN")
  w.Header().Set("Content-Type", "text/plain")
  w.Write([]byte("Set header for handler A."))
 }

 func handlerB(w http.ResponseWriter, req *http.Request) {
 w.Header().Set("X-Frame-Options", "SAMEORIGIN")
  w.Header().Set("Content-Type", "text/plain")
  w.Write([]byte("Set header for handler B."))
 }

Instead of setting header for each individual handler manually, you want to use a function to set the headers.

NOTE : This method can apply to Add headers as well

Solution :

Create a common SetHeaders() function that will write to http.ResponseWriter. For example :

 func SetHeaders(w http.ResponseWriter) {
 w.Header().Set("X-Frame-Options", "SAMEORIGIN")
 w.Header().Set("Content-Type", "text/plain")
 }

 func handlerA(w http.ResponseWriter, req *http.Request) {
 SetHeaders(w)
 w.Write([]byte("Set header for handler A."))
 }

 func handlerB(w http.ResponseWriter, req *http.Request) {
 SetHeaders(w)
 w.Write([]byte("Set header for handler B."))
 }