id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
35618	response.close() in a TestCase prematurely closes PostgreSQL connection and leads to psycopg2.InterfaceError	Anders Kaseorg		"If I call `response.close()` on an HTTP response from the test client within a `django.test.TestCase`, Django incorrectly closes the active PostgreSQL connection, causing future test requests to fail with `psycopg2.InterfaceError: connection already closed`.

This happens because `HttpResponseBase.close` [https://github.com/django/django/blob/5.0.7/django/http/response.py#L335 sends] `signals.request_finished`, which is [https://github.com/django/django/blob/5.0.7/django/db/__init__.py#L60 handled] by `django.db.close_old_connections`, which [https://github.com/django/django/blob/5.0.7/django/db/__init__.py#L57 calls] `BaseDatabaseWrapper.close_if_unusable_or_obsolete`, which [https://github.com/django/django/blob/5.0.7/django/db/backends/base/base.py#L596 observes] `self.get_autocommit() != self.settings_dict[""AUTOCOMMIT""]` (`False != True`) and closes the connection.

Any connection that’s within a transaction (such as the one opened by `TestCase`) will have `get_autocommit() == False`. It seems very wrong that the finishing of any request automatically triggers all connections in transactions to be immediately closed.

Minimal complete test project: https://gist.github.com/andersk/b4da5a106995b4c525595ea204675ee0

{{{
$ ./manage.py test
Found 1 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
E
======================================================================
ERROR: test (tests.MyTest.test)
----------------------------------------------------------------------
Traceback (most recent call last):
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/backends/base/base.py"", line 294, in _cursor
    return self._prepare_cursor(self.create_cursor(name))
                                ^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/utils/asyncio.py"", line 26, in inner
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/backends/postgresql/base.py"", line 332, in create_cursor
    cursor = self.connection.cursor()
             ^^^^^^^^^^^^^^^^^^^^^^^^
psycopg2.InterfaceError: connection already closed

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File ""/tmp/close-test/tests.py"", line 8, in test
    response = self.client.get(""/two"")
               ^^^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/test/client.py"", line 1049, in get
    response = super().get(path, data=data, secure=secure, headers=headers, **extra)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/test/client.py"", line 465, in get
    return self.generic(
           ^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/test/client.py"", line 617, in generic
    return self.request(**r)
           ^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/test/client.py"", line 1013, in request
    self.check_exception(response)
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/test/client.py"", line 743, in check_exception
    raise exc_value
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/core/handlers/exception.py"", line 55, in inner
    response = get_response(request)
               ^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/core/handlers/base.py"", line 197, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/my_urls.py"", line 7, in view
    with connection.cursor():
         ^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/utils/asyncio.py"", line 26, in inner
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/backends/base/base.py"", line 316, in cursor
    return self._cursor()
           ^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/backends/base/base.py"", line 293, in _cursor
    with self.wrap_database_errors:
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/utils.py"", line 91, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/backends/base/base.py"", line 294, in _cursor
    return self._prepare_cursor(self.create_cursor(name))
                                ^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/utils/asyncio.py"", line 26, in inner
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File ""/tmp/close-test/.direnv/python-3.12/lib/python3.12/site-packages/django/db/backends/postgresql/base.py"", line 332, in create_cursor
    cursor = self.connection.cursor()
             ^^^^^^^^^^^^^^^^^^^^^^^^
django.db.utils.InterfaceError: connection already closed

----------------------------------------------------------------------
Ran 1 test in 0.018s

FAILED (errors=1)
Destroying test database for alias 'default'...
}}}"	Uncategorized	closed	Database layer (models, ORM)	5.0	Normal	duplicate		Carlton Gibson Jon Janzen	Unreviewed	1	0	0	0	0	0