Respect 'using' in signals

admin_interface/models.py

@@ -17,19 +17,23 @@ class Theme(models.Model):
     @staticmethod
     def post_migrate_handler(**kwargs):
         del_cached_active_theme()
-        Theme.get_active_theme()
+        Theme.get_active_theme(**kwargs)
 
     @staticmethod
     def post_delete_handler(**kwargs):
         del_cached_active_theme()
-        Theme.get_active_theme()
+        Theme.get_active_theme(**kwargs)
 
     @staticmethod
     def post_save_handler(instance, **kwargs):
+
         del_cached_active_theme()
         if instance.active:
-            Theme.objects.exclude(pk=instance.pk).update(active=False)
-        Theme.get_active_theme()
+            objs_manager = Theme.objects
+            if "using" in kwargs:
+                objs_manager = objs_manager.using(kwargs["using"])
+            objs_manager.exclude(pk=instance.pk).update(active=False)
+        Theme.get_active_theme(**kwargs)
 
     @staticmethod
     def pre_save_handler(instance, **kwargs):
@@ -42,8 +46,10 @@ def pre_save_handler(instance, **kwargs):
                 pass
 
     @staticmethod
-    def get_active_theme():
+    def get_active_theme(*args, **kwargs):
         objs_manager = Theme.objects
+        if "using" in kwargs:
+            objs_manager = objs_manager.using(kwargs["using"])
         objs_active_qs = objs_manager.filter(active=True)
         objs_active_ls = list(objs_active_qs)
         objs_active_count = len(objs_active_ls)

tests/settings.py

@@ -90,6 +90,14 @@
         "HOST": "",
         "PORT": "",
     },
+    "postgres_2": {
+        "ENGINE": "django.db.backends.postgresql_psycopg2",
+        "NAME": "admin_interface_2",
+        "USER": "postgres",
+        "PASSWORD": "postgres",
+        "HOST": "",
+        "PORT": "",
+    },
 }
 
 github_workflow = os.environ.get("GITHUB_WORKFLOW")
@@ -98,8 +106,11 @@
     database_config["postgres"]["HOST"] = "127.0.0.1"
     database_config["postgres"]["PORT"] = "5432"
 
+replica_engine = "postgres_2" if database_engine == "postgres" else database_engine
+
 DATABASES = {
     "default": database_config.get(database_engine),
+    "replica": database_config.get(replica_engine),
 }
 
 USE_I18N = True

tests/test_models.py

@@ -4,9 +4,11 @@
 
 import random
 import shutil
+from unittest import expectedFailure
+from unittest.mock import Mock, patch
 
 from django.conf import settings
-from django.test import TestCase
+from django.test import TestCase, TransactionTestCase
 
 from admin_interface.models import Theme
 
@@ -88,3 +90,33 @@ def test_last_theme_activated_on_multiple_themes_activated(self):
     def test_repr(self):
         theme = Theme.get_active_theme()
         self.assertEqual("{0}".format(theme), "Django")
+
+
+class AdminInterfaceModelsMultiDBTestCase(TransactionTestCase):
+    databases = ["default", "replica"]
+
+    def setUp(self):
+        pass
+
+    def tearDown(self):
+        shutil.rmtree(settings.MEDIA_ROOT, ignore_errors=True)
+
+    def test_get_theme_from_default_db(self):
+        Theme.get_active_theme()
+
+    def test_get_theme_from_replica_db(self):
+        kwargs = {"using": "replica"}
+        replica_theme = Theme.get_active_theme(**kwargs)
+        assert "Default" not in replica_theme.name
+
+    def test_db_are_isolated(self):
+        Theme.objects.using("replica").create(name="Replica Active", active=True)
+        default_theme = Theme.get_active_theme()
+        kwargs = {"using": "replica"}
+        replica_theme = Theme.get_active_theme(**kwargs)
+        assert default_theme.name != replica_theme.name
+
+    @expectedFailure
+    def test_fail_for_wrong_db_defined_in_kwargs(self):
+        kwargs = {"using": "other"}
+        Theme.get_active_theme(**kwargs)