Include parent category in unique constraints

(cherry picked from commit a0b94a05)

CHANGELOG.rst

@@ -12,7 +12,7 @@ and this project adheres to `Semantic Versioning`_.
 Changed
 ~~~~~~~~
 
-* Ensure uniqueness per site of FAQ sections and categories.
+* Ensure uniqueness per site of FAQ sections and categories with parents.
 
 
 `2.0b0`_ - 2021-05-21

aleksis/apps/hjelp/migrations/0004_unique_constraints.py

@@ -44,6 +44,10 @@ class Migration(migrations.Migration):
         ),
         migrations.AddConstraint(
             model_name='issuecategory',
-            constraint=models.UniqueConstraint(fields=('site_id', 'name'), name='unique_category_name_per_site'),
+            constraint=models.UniqueConstraint(fields=('site_id', 'name'), condition=models.Q(parent='null'), name='unique_category_name_per_site_without_parent'),
+        ),
+        migrations.AddConstraint(
+            model_name='issuecategory',
+            constraint=models.UniqueConstraint(fields=('site_id', 'name', 'parent'), name='unique_category_name_per_site_with_parent'),
         ),
     ]

aleksis/apps/hjelp/models.py

@@ -102,6 +102,12 @@ class IssueCategory(ExtensibleModel):
 
         constraints = [
             models.UniqueConstraint(
-                fields=["site_id", "name"], name="unique_category_name_per_site"
-            )
+                fields=["site_id", "name"],
+                condition=models.Q(parent="null"),
+                name="unique_category_name_per_site_without_parent",
+            ),
+            models.UniqueConstraint(
+                fields=["site_id", "name", "parent"],
+                name="unique_category_name_per_site_with_parent",
+            ),
         ]