public IActionResult Get(string id)
        {
            if (string.IsNullOrWhiteSpace(id))
            {
                return(BadRequest(ErrorResponse.BadRequestError(1, "missing product id", nameof(id))));
            }

            var product = productCatalog.FindById(id);

            if (product == null)
            {
                return(NotFound());
            }
            return(Ok(product.MapTo <Product>()));
        }