feat: DomainGroup은 최소 1개 이상 존재하도록 수정

Author: MU-Software

app/admin_api/test/cms_test.py

@@ -211,8 +211,16 @@ def test_updating_non_empty_group_does_not_create_extra_sitemap(api_client, supe
 # ---- DomainGroup destroy ----------------------------------------------------
 
 
+@pytest.fixture
+def guard_group(superuser):
+    # destroy 테스트들이 "마지막 그룹 삭제 불가" 규칙에 걸리지 않도록 별도의 그룹을 시드.
+    return DomainGroup.objects.create(
+        name="guard", domains=["guard.pycon.kr"], created_by=superuser, updated_by=superuser
+    )
+
+
 @pytest.mark.django_db
-def test_destroy_domain_group_with_lone_root_succeeds_leaving_page(api_client, superuser):
+def test_destroy_domain_group_with_lone_root_succeeds_leaving_page(api_client, superuser, guard_group):
     # lone root만 함께 삭제. Page/Section은 보존 (dangling이 되더라도 의도적 삭제 회피로 안전성 우선).
     group = DomainGroup.objects.create(name="A", domains=["a.pycon.kr"], created_by=superuser, updated_by=superuser)
     page = Page.objects.create(title="A", subtitle="A", created_by=superuser, updated_by=superuser)
@@ -235,7 +243,7 @@ def test_destroy_domain_group_with_lone_root_succeeds_leaving_page(api_client, s
 
 
 @pytest.mark.django_db
-def test_destroy_domain_group_with_multiple_sitemaps_rejected(api_client, superuser):
+def test_destroy_domain_group_with_multiple_sitemaps_rejected(api_client, superuser, guard_group):
     group = DomainGroup.objects.create(name="A", domains=["a.pycon.kr"], created_by=superuser, updated_by=superuser)
     Sitemap.objects.create(name="r1", domain_group=group, route_code="", created_by=superuser, updated_by=superuser)
     Sitemap.objects.create(
@@ -250,7 +258,7 @@ def test_destroy_domain_group_with_multiple_sitemaps_rejected(api_client, superu
 
 
 @pytest.mark.django_db
-def test_destroy_domain_group_with_sitemap_having_children_rejected(api_client, superuser):
+def test_destroy_domain_group_with_sitemap_having_children_rejected(api_client, superuser, guard_group):
     group = DomainGroup.objects.create(name="A", domains=["a.pycon.kr"], created_by=superuser, updated_by=superuser)
     parent = Sitemap.objects.create(
         name="parent", domain_group=group, route_code="", created_by=superuser, updated_by=superuser
@@ -271,6 +279,16 @@ def test_destroy_domain_group_with_sitemap_having_children_rejected(api_client,
     assert group.deleted_at is None
 
 
+@pytest.mark.django_db
+def test_destroy_last_domain_group_rejected(api_client, domain_group):
+    # 유일한 그룹은 삭제 불가
+    assert DomainGroup.objects.filter_active().count() == 1
+    response = api_client.delete(reverse("v1:admin-domain-group-detail", kwargs={"pk": domain_group.id}))
+    assert response.status_code == http.HTTPStatus.BAD_REQUEST
+    domain_group.refresh_from_db()
+    assert domain_group.deleted_at is None
+
+
 # ---- Sitemap admin serializer exposes domain_group --------------------------
 
 

app/admin_api/views/cms.py

@@ -32,6 +32,9 @@ class DomainGroupAdminViewSet(JsonSchemaViewSet, viewsets.ModelViewSet):
     queryset = DomainGroup.objects.filter_active().select_related_with_user()
 
     def perform_destroy(self, instance: DomainGroup) -> None:
+        if DomainGroup.objects.filter_active().count() <= 1:
+            raise exceptions.ValidationError("마지막 DomainGroup은 삭제할 수 없습니다.")
+
         active = list(instance.sitemaps.filter_active())
         is_lone_root = (
             len(active) == 1 and active[0].parent_sitemap_id is None and not active[0].children.filter_active().exists()