public IActionResult DeleteShipment(int id)
        {
            var shipmentFromRepo = _repo.GetShipment(id);

            if (shipmentFromRepo == null)
            {
                return(NotFound());
            }
            _repo.DeleteShipment(shipmentFromRepo);
            if (!_repo.Save())
            {
                throw new Exception($"Error deleting shipment {id}.");
            }

            return(NoContent());
        }