Skip ready functions if not in main thread or plugins are not loaded yet

InvenTree/users/apps.py

@@ -5,7 +5,8 @@ import logging
 from django.apps import AppConfig
 from django.db.utils import OperationalError, ProgrammingError
 
-from InvenTree.ready import canAppAccessDatabase
+from InvenTree.ready import (canAppAccessDatabase, isInMainThread,
+                             isPluginRegistryLoaded)
 
 logger = logging.getLogger('inventree')
 
@@ -17,6 +18,11 @@ class UsersConfig(AppConfig):
 
     def ready(self):
         """Called when the 'users' app is loaded at runtime"""
+
+        # skip loading if plugins are not loaded or we run in a background thread
+        if not isPluginRegistryLoaded() or not isInMainThread():
+            return
+
         if canAppAccessDatabase(allow_test=True):
 
             try: