[Fix] Child products should not have product class

.github/workflows/ci.yml

@@ -41,7 +41,7 @@ jobs:
       matrix:
         python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
         django-version: ["3.2", "4.2", "5.2"]
-        oscar-version: ["3.2", "4.0"]
+        oscar-version: ["3.2", "4.0", "4.1"]
         exclude:
           - python-version: "3.13"
             django-version: "3.2"
@@ -59,6 +59,8 @@ jobs:
             django-version: "5.2"
           - python-version: "3.8"
             oscar-version: "4.0"
+          - python-version: "3.8"
+            oscar-version: "4.1"
     steps:
       - name: Download src dir
         uses: actions/download-artifact@v4

oscarapi/fixtures/product.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <django-objects version="1.0">
     <object pk="1" model="catalogue.product">
-        <field type="CharField" name="structure">parent</field>
+        <field type="CharField" name="structure">standalone</field>
         <field type="CharField" name="upc">1234</field>
         <field to="catalogue.product" name="parent" rel="ManyToOneRel">
             <None/>
@@ -18,10 +18,28 @@
         <field type="BooleanField" name="is_discountable">True</field>
         <field to="catalogue.option" name="product_options" rel="ManyToManyRel"/>
     </object>
+    <object pk="5" model="catalogue.product">
+        <field type="CharField" name="structure">parent</field>
+        <field type="CharField" name="upc">parent-1234</field>
+        <field to="catalogue.product" name="parent" rel="ManyToOneRel">
+            <None/>
+        </field>
+        <field type="CharField" name="title">Oscar T-shirt</field>
+        <field type="SlugField" name="slug">parent-1234</field>
+        <field type="TextField" name="description">Hank</field>
+        <field to="catalogue.productclass" name="product_class" rel="ManyToOneRel">1</field>
+        <field type="FloatField" name="rating">
+            <None/>
+        </field>
+        <field type="DateTimeField" name="date_created">2013-12-12T16:33:57.426000+00:00</field>
+        <field type="DateTimeField" name="date_updated">2013-12-12T16:33:57.426000+00:00</field>
+        <field type="BooleanField" name="is_discountable">True</field>
+        <field to="catalogue.option" name="product_options" rel="ManyToManyRel"/>
+    </object>
     <object pk="2" model="catalogue.product">
         <field type="CharField" name="structure">child</field>
         <field type="CharField" name="upc">child-1234</field>
-        <field to="catalogue.product" name="parent" rel="ManyToOneRel">1</field>
+        <field to="catalogue.product" name="parent" rel="ManyToOneRel">5</field>
         <field type="CharField" name="title"/>
         <field type="SlugField" name="slug">oscar-t-shirt-child</field>
         <field type="TextField" name="description"/>

oscarapi/serializers/admin/product.py

@@ -93,10 +93,14 @@ def update(self, instance, validated_data):
         categories = validated_data.pop("categories", None)
         recommended_products = validated_data.pop("recommended_products", None)
         children = validated_data.pop("children", None)
+        structure = validated_data.get("structure", instance.structure)
         # Child products are not supposed to have a product class, their product
         # class comes from the parent product.
-        if instance.is_child:
-            validated_data.pop("product_class", None)
+        if structure == Product.CHILD:
+            validated_data["product_class"] = None
+        else:
+            # Parent and standalone products are not supposed to have a parent
+            validated_data["parent"] = None
 
         with transaction.atomic():  # it is all or nothing!
             # update instance
@@ -118,6 +122,9 @@ def update(self, instance, validated_data):
                     else:
                         _categories.set(categories)
 
+            if instance.is_child:
+                instance.categories.all().delete()
+
             if recommended_products is not None:
                 with fake_autocreated(
                     instance.recommended_products
@@ -148,11 +155,17 @@ def update(self, instance, validated_data):
                     self.update_relation("options", _product_options, new_options)
 
             self.update_relation("images", instance.images, images)
-            self.update_relation("stockrecords", instance.stockrecords, stockrecords)
             self.update_relation(
                 "attributes", instance.attribute_values, attribute_values
             )
 
+            if instance.is_parent:
+                instance.stockrecords.all().delete()
+            else:
+                self.update_relation(
+                    "stockrecords", instance.stockrecords, stockrecords
+                )
+
             if (
                 self.partial
             ):  # we need to clean up all the attributes with wrong product class

oscarapi/serializers/product.py

@@ -460,15 +460,30 @@ class BaseProductSerializer(OscarModelSerializer):
     )
 
     def validate(self, attrs):
-        if "structure" in attrs and "parent" in attrs:
+        structure = attrs.get("structure", None)
+        if structure and "parent" in attrs:
             if attrs["structure"] == Product.CHILD and attrs["parent"] is None:
                 raise serializers.ValidationError(_("child without parent"))
-        if "structure" in attrs and "product_class" in attrs:
+        if structure and "product_class" in attrs:
             if attrs["product_class"] is None and attrs["structure"] != Product.CHILD:
                 raise serializers.ValidationError(
                     _("product_class can not be empty for structure %(structure)s")
                     % attrs
                 )
+        if (
+            self.instance
+            and structure
+            and structure != Product.PARENT
+            and self.instance.structure == Product.PARENT
+            and self.instance.children.exists()
+        ):
+            raise serializers.ValidationError(
+                {
+                    "structure": _(
+                        "Cannot convert parent product with children to a non-parent"
+                    )
+                }
+            )
 
         return super(BaseProductSerializer, self).validate(attrs)