ProductEventHandler.cs

namespace Domain.ProductInformation.EventHandlers
{
    public class ProductInformationHandler :
        IHandleEvents<ProductInformation>
    {
        private readonly ReviewUsecase _reviewUseCase;
        private readonly IStorePurchaseOrders _purchaseOrderStore;
        private readonly IStoreProducts _productStore;

        public ProductInformationHandler(
            ReviewUsecase reviewUseCase,
            IStorePurchaseOrders purchaseOrderStore,
            IStoreProducts productStore)
        {
            _reviewUseCase = reviewUseCase;
            _purchaseOrderStore = purchaseOrderStore;
            _productStore = productStore;
        }

        public async Task Handle(ProductInformation eventToHandle)
        {                    
            var product = eventToHandle.ToEntity();
            await _productStore.Save();

            var purchaseOrderItems = await _purchaseOrderStore
                .GetFor(eventToHandle.ProductId);

            foreach (var item in purchaseOrderItems)
            {
                await _reviewUseCase.Execute(item, product);
            }
        }
    }
}