public async Task <JsonResult> AddSubcription(string subscribedProduct)
        {
            SubscribedProductDto subscribedProductDto = JsonConvert.DeserializeObject <SubscribedProductDto>(subscribedProduct);

            try
            {
                var subscrib = await _productService.AddSubscription(subscribedProductDto);

                return(Json(new { success = true, result = subscrib }));
            }
            catch (Exception ex)
            {
                return(Json(new { success = false, result = ex.Message }));
            }
        }
        public async Task <SubscribedProduct> AddSubscription(SubscribedProductDto subscribedProductDto)
        {
            var product = await _db.Products.FirstOrDefaultAsync(p => p.Id == subscribedProductDto.ProductId);

            var newSubscribedProduct = new SubscribedProduct()
            {
                UserId    = subscribedProductDto.UserId,
                ProductId = subscribedProductDto.ProductId
            };
            await _db.SubscribedProducts.AddAsync(newSubscribedProduct);

            await _db.SaveChangesAsync();

            return(newSubscribedProduct);
        }