package middleware import "net/http" // Header adds the given response headers to the upcoming `http.ResponseWriter`. func Header(values http.Header) func(http.Handler) http.Handler { return func(next http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { for key, value := range values { w.Header()[key] = value } next.ServeHTTP(w, r) }) } }