anchor.diff:          JSON ->
               JSONMap = json_utils:decode_map(json_utils:encode(JSON)),
               ok = logical_file_manager:set_metadata(
  -                SessionId, {guid, FileId}, <<"json">>, JSONMap, []
  +                SessionId, {guid, FileId}, json, JSONMap, []
               )
       end,
       case proplists:get_value(<<"rdf">>, Data) of
  
positive.code:         _ -> Basic
      end,
      {ok, JSON} = logical_file_manager:get_metadata(
          SessionId, {guid, FileId}, <<"json">>, [], false
      ),
      JSONVal = case is_map(JSON) andalso map_size(JSON) of
          0 -> null;
          _ -> json_utils:decode(json_utils:encode_map(JSON))
      end,
      {ok, RDF} = logical_file_manager:get_metadata(
          SessionId, {guid, FileId}, <<"rdf">>, [], false
      ),
      RDFVal = case RDF of
          undefined -> null;
          _ -> RDF
      end,
      {ok, [
  
negative.code:                 SessionId, {guid, FileId}, Key
              )
          end, XattrKeys),
      ok = logical_file_manager:remove_metadata(
          SessionId, {guid, FileId}, json
      ),
      ok = logical_file_manager:remove_metadata(
          SessionId, {guid, FileId}, rdf
      ),
      ok.
  
  