anchor.diff:  
       AllRawParams = RawParams#{path => cowboy_req:path_info(Req)},
       AllOptionalParams = #{
  -        path => {list_of_binaries, fun(PathTokens) ->
  -            JoinedPath = str_utils:join_as_binaries(PathTokens, <<"/">>),
  -            case filepath_utils:sanitize(JoinedPath) of
  -                {error, _} -> throw(?ERROR_BAD_VALUE_FILE_PATH);
  -                {ok, _} -> ok
  -            end,
  -            {true, PathTokens}
  -        end
  -        },
  +        path => {list_of_binaries, fun assert_valid_file_path/1},
           <<"follow_symlinks">> => {boolean, any}
       },
   
  
positive.code: 
  
  %% @private
  -spec resolve_target_file(middleware:req()) -> fslogic_worker:file_guid() | no_return().
  resolve_target_file(#op_req{
      operation = Operation,
  
negative.code:             {
                  RawParams#{path => cowboy_req:path_info(Req)},
                  #{<<"create_parents">> => {boolean, any}},
                  #{path => {list_of_binaries, fun
                      ([]) ->
                          throw(?ERROR_MISSING_REQUIRED_VALUE(<<"path">>));
                      (PathTokens) ->
                          assert_valid_file_path(PathTokens),
                          {true, PathTokens}
                  end
                  }}
              }
  