Bugfix init: move Database access from checks into post-migate signal

inventory/apps.py

@@ -16,3 +16,4 @@ class InventoryConfig(AppConfig):
 
     def ready(self):
         import inventory.checks  # noqa
+        import inventory.signals  # noqa

inventory/checks.py

@@ -1,8 +1,6 @@
 from pathlib import Path
 
-from django.core.checks import Error, Warning, register
-
-from inventory.permissions import get_or_create_normal_user_group, setup_normal_user_permissions
+from django.core.checks import Error, register
 
 
 @register()
@@ -17,25 +15,3 @@ def inventory_checks(app_configs, **kwargs):
             )
         )
     return errors
-
-
-@register()
-def inventory_user_groups(app_configs, **kwargs):
-    """
-    Setup PyInventory user groups
-    """
-    warnings = []
-
-    normal_user_group, created = get_or_create_normal_user_group()
-    if created:
-        warnings.append(
-            Warning(f'User group {normal_user_group} created')
-        )
-
-    updated = setup_normal_user_permissions(normal_user_group)
-    if updated:
-        warnings.append(
-            Warning(f'Update permissions for {normal_user_group}')
-        )
-
-    return warnings

inventory/signals.py

@@ -0,0 +1,15 @@
+from django.db.models.signals import post_migrate
+from django.dispatch import receiver
+
+from inventory.permissions import get_or_create_normal_user_group, setup_normal_user_permissions
+
+
+@receiver(post_migrate)
+def post_migrate_callback(sender, **kwargs):
+    normal_user_group, created = get_or_create_normal_user_group()
+    if created:
+        print(f'User group {normal_user_group} created')
+
+    updated = setup_normal_user_permissions(normal_user_group)
+    if updated:
+        print(f'Update permissions for {normal_user_group}')