public CollectionModel RefuseSign([FromBody] SignTaskDTO signTaskDTO)
        {
            try {
                AssertSignTaskDTOIsValid(signTaskDTO);

                FixedList <SignEventDTO> refuseSignEvents = ESignUseCases.RefuseSign(signTaskDTO);

                return(GetResponse(refuseSignEvents));
            } catch (Exception e) {
                throw base.CreateHttpException(e);
            }
        }
        private void AssertSignTaskDTOIsValid(SignTaskDTO signTaskDTO)
        {
            base.RequireBody(signTaskDTO);

            ESignUseCases.EnsureValidSignTaskDTO(signTaskDTO);
        }