public void Delete(int productId)
{
var dbProduct = productRepository
.GetById(productId);
if (dbProduct == null)
{
throw new ValidatorException("Unkonwn product");
}
var dbProductCategories = productCategoryRepository
.GetByProductId(productId)
.ToList();
productCategoryRepository.DeleteCategories(dbProductCategories);
productRepository.Delete(dbProduct);
}