package render import ( "net/http" ) // Render http reponse render. type Render interface { // Render render it to http response writer. Render(http.ResponseWriter) error // WriteContentType write content-type to http response writer. WriteContentType(w http.ResponseWriter) } var ( _ Render = JSON{} _ Render = MapJSON{} _ Render = XML{} _ Render = String{} _ Render = Redirect{} _ Render = Data{} _ Render = PB{} ) func writeContentType(w http.ResponseWriter, value []string) { header := w.Header() if val := header["Content-Type"]; len(val) == 0 { header["Content-Type"] = value } }