Fix migration corner case

Author: AlanCoding

ansible_base/rbac/managed.py

@@ -42,6 +42,13 @@ def get_content_type(self, apps):
         # NOTE: this is subject to major migration-related hazards
         try:
             content_type_cls = apps.get_model('dab_rbac', 'DABContentType')
+            if not content_type_cls.objects.exists():
+                # Extra special migration hazard
+                # an old app migration file is trying to create managed roles with current models
+                # but permissions are not yet created
+                from ansible_base.rbac.management import sync_dab_permissions
+
+                sync_dab_permissions(apps=apps)
         except LookupError:
             content_type_cls = apps.get_model('contenttypes', 'ContentType')
         return content_type_cls.objects.get_for_model(model)

ansible_base/rbac/management/_old.py

@@ -16,6 +16,7 @@ def create_dab_permissions(app_config, verbosity=2, interactive=True, using=DEFA
     this will only create permissions for registered models
     """
     if not getattr(app_config, 'models_module', None):
+        logger.info(f'Not running permission creation method for {app_config.label} because it has no models')
         return
 
     # exit early if nothing is registered for this app
@@ -39,10 +40,12 @@ def create_dab_permissions(app_config, verbosity=2, interactive=True, using=DEFA
         app_config = apps.get_app_config(app_label)
         ContentType = apps.get_model("contenttypes", "ContentType")
         Permission = apps.get_model("dab_rbac", "DABPermission")
-    except LookupError:
+    except LookupError as exc:
+        logger.info(f'Not running create_dab_permissions because model not available {str(exc)}')
         return
 
     if not router.allow_migrate_model(using, Permission):
+        logger.info('Not running create_dab_permissions because permission model does not allow migrating')
         return
 
     # This will hold the permissions we're looking for as (content_type, (codename, name))