Replace DatabaseWrapper.__getattr__() with a simpler database attribute

django_mongodb_backend/base.py

@@ -4,6 +4,7 @@
 from django.core.exceptions import ImproperlyConfigured
 from django.db.backends.base.base import BaseDatabaseWrapper
 from django.utils.asyncio import async_unsafe
+from django.utils.functional import cached_property
 from pymongo.collection import Collection
 from pymongo.driver_info import DriverInfo
 from pymongo.mongo_client import MongoClient
@@ -149,13 +150,13 @@ def get_database(self):
             return OperationDebugWrapper(self)
         return self.database
 
-    def __getattr__(self, attr):
-        """Connect to the database the first time `database` is accessed."""
-        if attr == "database":
-            if self.connection is None:
-                self.connect()
-            return getattr(self, attr)
-        raise AttributeError(attr)
+    @cached_property
+    def database(self):
+        """Connect to the database the first time it's accessed."""
+        if self.connection is None:
+            self.connect()
+        # Cache the database attribute set by init_connection_state()
+        return self.database
 
     def init_connection_state(self):
         self.database = self.connection[self.settings_dict["NAME"]]

tests/backend_/test_base.py

@@ -1,5 +1,6 @@
 from django.core.exceptions import ImproperlyConfigured
 from django.db import connection
+from django.db.backends.signals import connection_created
 from django.test import SimpleTestCase, TestCase
 
 from django_mongodb_backend.base import DatabaseWrapper
@@ -21,3 +22,23 @@ def test_set_autocommit(self):
         self.assertIs(connection.get_autocommit(), False)
         connection.set_autocommit(True)
         self.assertIs(connection.get_autocommit(), True)
+
+    def test_connection_created_database_attr(self):
+        """
+        connection.database is available in the connection_created signal.
+        """
+        data = {}
+
+        def receiver(sender, connection, **kwargs):  # noqa: ARG001
+            data["database"] = connection.database
+
+        connection_created.connect(receiver)
+        connection.close()
+        # Accessing database implicitly connects.
+        connection.database  # noqa: B018
+        self.assertIs(data["database"], connection.database)
+        connection.close()
+        connection_created.disconnect(receiver)
+        data.clear()
+        connection.connect()
+        self.assertEqual(data, {})