fix headers

server.go

@@ -80,12 +80,13 @@ func (s *Server) Serve(w http.ResponseWriter, r *http.Request) {
 	}
 	defer resp.Body.Close()
 
-	w.WriteHeader(resp.StatusCode)
 	for k, v := range resp.Header {
+		log.Println(k, v)
 		for _, s := range v {
 			w.Header().Add(k, s)
 		}
 	}
+	w.WriteHeader(resp.StatusCode)
 	s.xfer(r.Context(), w, resp.Body)
 }