anchor.diff:  
   route(#{method := <<"GET">>} = Req, State) ->
     check_database_db(Req, State);
  -route(Req, State) ->
  -  {ok, Req2, State} = barrel_http_reply:error(405, Req, []),
  +route(Req, _State) ->
  +  {ok, Req2, _} = barrel_http_reply:error(405, Req, []),
     {stop, Req2}.
   
   check_database_db(Req, State) ->
  
positive.code:       check_params(Req, State#state{database=Database});
      _Error ->
        _ = lager:info("unknown database requested: ~p~n", [Database]),
        {ok, Req3, S} = barrel_http_reply:error(400, "unknown database", Req, State),
        {stop, Req3}
    end.
  
  
negative.code:   Params = cowboy_req:parse_qs(Req),
    case parse_params(Params, StateDefault) of
      {error, {unknown_param, _}} ->
        {ok, Req2, _S} = barrel_http_reply:error(400, "unknown parameter", Req, State),
        {stop, Req2};
      {ok, State2} ->
        check_eventsource_headers(Req, State2)
  