public InvoiceItemDto Delete(IObjectIdentifier <ulong> id)
        {
            var item = _repository.FindById(id);

            _repository.Delete(item.Id);
            return(InvoiceItemDto.FromDomain(item));
        }
 public InvoiceItemDto GetById(IObjectIdentifier <ulong> id) => InvoiceItemDto.FromDomain(_repository.FindById(id));