db: Force use of TimeTrackingCursor to work around Django 4.2 bug.

Effectively revert commit b4cf9ad777 to
work around https://code.djangoproject.com/ticket/34466.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

zerver/lib/db.py

@@ -1,5 +1,17 @@
 import time
-from typing import Any, Callable, Dict, Iterable, List, Mapping, Sequence, TypeVar, Union
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    Iterable,
+    List,
+    Mapping,
+    Optional,
+    Sequence,
+    TypeVar,
+    Union,
+    overload,
+)
 
 from psycopg2.extensions import connection, cursor
 from psycopg2.sql import Composable
@@ -48,6 +60,41 @@ class TimeTrackingConnection(connection):
         self.queries: List[Dict[str, str]] = []
         super().__init__(*args, **kwargs)
 
+    @overload
+    def cursor(
+        self,
+        name: Union[str, bytes, None] = ...,
+        *,
+        withhold: bool = ...,
+        scrollable: Optional[bool] = ...,
+    ) -> TimeTrackingCursor:
+        ...
+
+    @overload
+    def cursor(
+        self,
+        name: Union[str, bytes, None] = ...,
+        *,
+        cursor_factory: Callable[..., CursorT] = ...,
+        withhold: bool = ...,
+        scrollable: Optional[bool] = ...,
+    ) -> CursorT:
+        ...
+
+    @overload
+    def cursor(
+        self,
+        name: Union[str, bytes, None],
+        cursor_factory: Callable[..., CursorT] = ...,
+        withhold: bool = ...,
+        scrollable: Optional[bool] = ...,
+    ) -> CursorT:
+        ...
+
+    def cursor(self, *args: Any, **kwargs: Any) -> cursor:
+        kwargs["cursor_factory"] = TimeTrackingCursor
+        return super().cursor(*args, **kwargs)
+
 
 def reset_queries() -> None:
     from django.db import connections

zproject/computed_settings.py

@@ -7,7 +7,7 @@ from typing import Any, Dict, Final, List, Tuple, Union
 from urllib.parse import urljoin
 
 from scripts.lib.zulip_tools import get_tornado_ports
-from zerver.lib.db import TimeTrackingConnection, TimeTrackingCursor
+from zerver.lib.db import TimeTrackingConnection
 
 from .config import (
     DEPLOY_ROOT,
@@ -282,7 +282,6 @@ DATABASES: Dict[str, Dict[str, Any]] = {
         "CONN_MAX_AGE": 600,
         "OPTIONS": {
             "connection_factory": TimeTrackingConnection,
-            "cursor_factory": TimeTrackingCursor,
         },
     }
 }

zproject/test_extra_settings.py

@@ -4,7 +4,7 @@ from typing import Dict, List, Optional, Tuple
 import ldap
 from django_auth_ldap.config import LDAPSearch
 
-from zerver.lib.db import TimeTrackingConnection, TimeTrackingCursor
+from zerver.lib.db import TimeTrackingConnection
 from zproject.settings_types import OIDCIdPConfigDict, SAMLIdPConfigDict, SCIMConfigDict
 
 from .config import DEPLOY_ROOT, get_from_file_if_exists
@@ -36,7 +36,6 @@ DATABASES["default"] = {
     "TEST_NAME": "django_zulip_tests",
     "OPTIONS": {
         "connection_factory": TimeTrackingConnection,
-        "cursor_factory": TimeTrackingCursor,
     },
 }