Fix filtering products by category, subcategory, producer, components…

…, tags and promotions; add new fields, ordering options and inlines to the Admin panel for categories, subcategories, components, tags, producers, promotions, coupons and products; update tests

backend/api/filters.py

@@ -4,16 +4,22 @@
 from products.models import Product
 
 
+class CharFilterInFilter(rf_filters.BaseInFilter, rf_filters.CharFilter):
+    """Custom char filter allowing comma-separated incoming values."""
+
+    pass
+
+
 class ProductFilter(rf_filters.FilterSet):
     """Class for filtering products."""
 
     name = rf_filters.CharFilter(method="startswith_contains_union_method")
-    category = rf_filters.AllValuesMultipleFilter(field_name="category__slug")
-    subcategory = rf_filters.AllValuesMultipleFilter(field_name="subcategory__slug")
-    producer = rf_filters.AllValuesMultipleFilter(field_name="producer__slug")
-    components = rf_filters.AllValuesMultipleFilter(field_name="components__slug")
-    tags = rf_filters.AllValuesMultipleFilter(field_name="tags__slug")
-    promotions = rf_filters.AllValuesMultipleFilter(field_name="promotions__slug")
+    category = CharFilterInFilter(field_name="category__slug")
+    subcategory = CharFilterInFilter(field_name="subcategory__slug")
+    producer = CharFilterInFilter(field_name="producer__slug")
+    components = CharFilterInFilter(field_name="components__slug")
+    tags = CharFilterInFilter(field_name="tags__slug")
+    promotions = CharFilterInFilter(field_name="promotions__slug")
     is_favorited = rf_filters.NumberFilter(method="product_boolean_methods")
     min_price = rf_filters.NumberFilter(method="get_min_price")
     max_price = rf_filters.NumberFilter(method="get_max_price")

backend/orders/shopping_carts.py

@@ -3,9 +3,7 @@
 from django.utils import timezone
 
 from core.loggers import logger
-from products.models import Coupon, Product
-
-PRICE_DECIMAL_PLACES = 2
+from products.models import PRICE_DECIMAL_PLACES, Coupon, Product
 
 
 class ShopCart(object):