Respect 'using' in signals (#200)

.gitignore

@@ -5,6 +5,10 @@ __pycache__/
 # C extensions
 *.so
 
+## Local setup
+.vscode/
+.venv/
+
 # Distribution / packaging
 .Python
 env/

admin_interface/models.py

@@ -17,19 +17,22 @@ class Theme(models.Model):
     @staticmethod
     def post_migrate_handler(**kwargs):
         del_cached_active_theme()
-        Theme.get_active_theme()
+        db = kwargs["using"]
+        Theme.get_active_theme(database=db)
 
     @staticmethod
     def post_delete_handler(**kwargs):
         del_cached_active_theme()
-        Theme.get_active_theme()
+        db = kwargs["using"]
+        Theme.get_active_theme(database=db)
 
     @staticmethod
     def post_save_handler(instance, **kwargs):
         del_cached_active_theme()
+        db = kwargs["using"]
         if instance.active:
-            Theme.objects.exclude(pk=instance.pk).update(active=False)
-        Theme.get_active_theme()
+            Theme.objects.using(db).exclude(pk=instance.pk).update(active=False)
+        Theme.get_active_theme(database=db)
 
     @staticmethod
     def pre_save_handler(instance, **kwargs):
@@ -42,8 +45,8 @@ class Theme(models.Model):
                 pass
 
     @staticmethod
-    def get_active_theme():
-        objs_manager = Theme.objects
+    def get_active_theme(database="default"):
+        objs_manager = Theme.objects.using(database)
         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 @@ database_config = {
         "HOST": "",
         "PORT": "",
     },
+    "postgres_replica": {
+        "ENGINE": "django.db.backends.postgresql_psycopg2",
+        "NAME": "admin_interface_2",
+        "USER": "postgres",
+        "PASSWORD": "postgres",
+        "HOST": "",
+        "PORT": "",
+    },
 }
 
 github_workflow = os.environ.get("GITHUB_WORKFLOW")
@@ -97,9 +105,16 @@ if github_workflow:
     database_config["postgres"]["NAME"] = "postgres"
     database_config["postgres"]["HOST"] = "127.0.0.1"
     database_config["postgres"]["PORT"] = "5432"
+    database_config["postgres_replica"]["HOST"] = "127.0.0.1"
+    database_config["postgres_replica"]["PORT"] = "5432"
+
+replica_engine = (
+    "postgres_replica" 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 +4,10 @@ from __future__ import unicode_literals
 
 import random
 import shutil
+from unittest import expectedFailure
 
 from django.conf import settings
-from django.test import TestCase
+from django.test import TestCase, TransactionTestCase
 
 from admin_interface.models import Theme
 
@@ -16,6 +17,7 @@ class AdminInterfaceModelsTestCase(TestCase):
         pass
 
     def tearDown(self):
+        Theme.objects.all().delete()
         shutil.rmtree(settings.MEDIA_ROOT, ignore_errors=True)
 
     def __test_active_theme(self):
@@ -88,3 +90,28 @@ class AdminInterfaceModelsTestCase(TestCase):
     def test_repr(self):
         theme = Theme.get_active_theme()
         self.assertEqual("{0}".format(theme), "Django")
+
+
+class AdminInterfaceModelsMultiDBTestCase(TestCase):
+    databases = ["default", "replica"]
+
+    @classmethod
+    def setUpTestData(cls):
+        Theme.objects.using("default").create(name="Change Active", active=True)
+
+    def test_get_theme_from_default_db(self):
+        de_theme = Theme.get_active_theme()
+        assert de_theme.name == "Change Active"
+
+    def test_get_theme_from_replica_db(self):
+        replica_theme = Theme.get_active_theme(database="replica")
+        assert replica_theme.name == "Django"
+
+    def test_db_are_isolated(self):
+        default_theme = Theme.get_active_theme()
+        replica_theme = Theme.get_active_theme(database="replica")
+        assert default_theme.name != replica_theme.name
+
+    @expectedFailure
+    def test_fail_for_wrong_db_defined_in_kwargs(self):
+        Theme.get_active_theme(database="other")