public IHttpActionResult Post(ProductModel productModel)
        {
            try
            {
                if (ModelState.IsValid)
                {
                    var product = _mapper.Map <Product>(productModel);

                    _productRepository.AddItem(product);
                    if (_productRepository.SaveChanges())
                    {
                        var newProduct = _mapper.Map <ProductModel>(product);
                        return(CreatedAtRoute("DefaultApi", new { id = product.Id }, newProduct));
                    }
                }
            }
            catch (Exception ex)
            {
                return(InternalServerError(ex));
            }
            return(BadRequest(ModelState));
        }