Prevent generation of useless migrations upon settings change

core/migrations/0029_auto_20180426_2013.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import core.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0028_auto_20171216_2044'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='page',
+            name='owner_group',
+            field=models.ForeignKey(verbose_name='owner group', default=core.models.Page.get_default_owner_group, related_name='owned_page', to='core.Group'),
+        ),
+    ]

core/models.py

@@ -920,8 +920,10 @@ class Page(models.Model):
     # Attention: this field may not be valid until you call save(). It's made for fast query, but don't rely on it when
     # playing with a Page object, use get_full_name() instead!
     _full_name = models.CharField(_('page name'), max_length=255, blank=True)
+    # This function prevents generating migration upon settings change
+    def get_default_owner_group(): return settings.SITH_GROUP_ROOT_ID
     owner_group = models.ForeignKey(Group, related_name="owned_page", verbose_name=_("owner group"),
-                                    default=settings.SITH_GROUP_ROOT_ID)
+                                    default=get_default_owner_group)
     edit_groups = models.ManyToManyField(Group, related_name="editable_page", verbose_name=_("edit group"), blank=True)
     view_groups = models.ManyToManyField(Group, related_name="viewable_page", verbose_name=_("view group"), blank=True)
     lock_user = models.ForeignKey(User, related_name="locked_pages", verbose_name=_("lock user"), blank=True, null=True, default=None)