def add(request, product_key): postdata = request.POST.copy() quantity = int(postdata.get('quantity', 1)) product = Product.get(product_key) item = CartItem.all().filter('product = ', product).filter('cart_id = ', get_cart_id(request)).get() if not item: item = CartItem() item.product = product item.quantity = quantity item.cart_id = get_cart_id(request) item.put() else: item.quantity = item.quantity + quantity item.put()