public async Task <IEnumerable <ChatMessageDTO> > GetAllMessagesByUserId(Guid userId) { _logger.Info(String.Format($"{"ChatService",-20} >>> {"GetAllMessagesByUserId",-20} >>> {"Start",-10} >>> {"UserId",-10}{userId}")); IEnumerable <ChatMessageDTO> result = null; if (userId == null || userId == Guid.Empty) { return(result); } result = await _chatRepository.GetAllMessagesByUserId(userId); _logger.Debug($"{"ChatService:",-20} >>> {"GetAllMessagesByUserId",-20} >>> {"Result:",-10} {JsonConvert.SerializeObject(result)}, {"UserId:",-10}{userId}."); return(result); }