public Result Handle(CreateBookCommand command)
        {
            var validationResult = Validate(command, _createBookCommandValidaor);

            if (validationResult.IsValid)
            {
                var book = BookMapper.CommandToEntity(command);
                _bookRepository.Add(book);
                _bookRepository.SaveChanges();

                var newBook = _bookRepository.GetById(book.Id);
                _eventPublisher.Publish(BookMapper.EntityToEvent(newBook));
            }

            return(Return());
        }