handlers.py 文件源码

def categories_changed_handler(sender, **kwargs):
    """
        ?????????? ??????? ????????? ???-?? ??????? ?????????,
        ??????????? ? ????????? ? ?? ?????????????.

        ???????????? ??? ?????????? ????????? ??????? ? ?????? ?????????.
    """
    categories = kwargs.get('categories')
    include_self = kwargs.get('include_self', True)
    if isinstance(categories, ShopCategory):
        # ????????? ?????????
        categories = ShopCategory.objects.filter(pk=categories.pk)
    elif isinstance(categories, (int, str)):
        # ?????? ??? ?????, ?????????? ID ?????????
        categories = ShopCategory.objects.filter(pk=categories)
    elif isinstance(categories, (list, tuple, set, ValuesListQuerySet)):
        # ?????? ????? ??? ?????, ?????????? ID ?????????
        categories = ShopCategory.objects.filter(pk__in=categories)
    elif isinstance(categories, QuerySet) and categories.model is ShopCategory:
        # QuerySet ?????????
        pass
    else:
        raise TypeError('Invalid categories for signal "categories_changed"')

    ancestors = categories.get_ancestors(
        include_self=include_self
    ).filter(
        is_visible=True
    ).order_by('tree_id', '-level').values_list('id', flat=True)

    with transaction.atomic():
        for category_id in ancestors:
            ShopCategory.objects.filter(pk=category_id).update(
                total_product_count=RawSQL(
                    'SELECT shop_shopcategory.product_count + '
                    'COALESCE(SUM(ssc.total_product_count), 0) '
                    'FROM shop_shopcategory AS ssc '
                    'WHERE ssc.parent_id = shop_shopcategory.id '
                    'AND ssc.is_visible = TRUE',
                    ()
                )
            )