============================================ Django 3.1 release notes - UNDER DEVELOPMENT ============================================ *Expected August 2020* Welcome to Django 3.1! These release notes cover the :ref:`new features `, as well as some :ref:`backwards incompatible changes ` you'll want to be aware of when upgrading from Django 3.0 or earlier. We've :ref:`dropped some features` that have reached the end of their deprecation cycle, and we've :ref:`begun the deprecation process for some features `. See the :doc:`/howto/upgrade-version` guide if you're updating an existing project. Python compatibility ==================== Django 3.1 supports Python 3.6, 3.7, and 3.8. We **highly recommend** and only officially support the latest release of each series. .. _whats-new-3.1: What's new in Django 3.1 ======================== Minor features -------------- :mod:`django.contrib.admin` ~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.admindocs` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.auth` ~~~~~~~~~~~~~~~~~~~~~~~~~~ * The default iteration count for the PBKDF2 password hasher is increased from 180,000 to 216,000. * Added the :setting:`PASSWORD_RESET_TIMEOUT` setting to define the minimum number of seconds a password reset link is valid for. This is encouraged instead of deprecated ``PASSWORD_RESET_TIMEOUT_DAYS``, which will be removed in Django 4.0. :mod:`django.contrib.contenttypes` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.gis` ~~~~~~~~~~~~~~~~~~~~~~~~~ * :lookup:`relate` lookup is now supported on MariaDB. * Added the :attr:`.LinearRing.is_counterclockwise` property. * :class:`~django.contrib.gis.db.models.functions.AsGeoJSON` is now supported on Oracle. * Added the :class:`~django.contrib.gis.db.models.functions.AsWKB` and :class:`~django.contrib.gis.db.models.functions.AsWKT` functions. :mod:`django.contrib.messages` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.postgres` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * The new :class:`~django.contrib.postgres.indexes.BloomIndex` class allows creating ``bloom`` indexes in the database. The new :class:`~django.contrib.postgres.operations.BloomExtension` migration operation installs the ``bloom`` extension to add support for this index. * :meth:`~django.db.models.Model.get_FOO_display` now supports :class:`~django.contrib.postgres.fields.ArrayField` and :class:`~django.contrib.postgres.fields.RangeField`. * The new :lookup:`rangefield.lower_inc`, :lookup:`rangefield.lower_inf`, :lookup:`rangefield.upper_inc`, and :lookup:`rangefield.upper_inf` allows querying :class:`~django.contrib.postgres.fields.RangeField` by a bound type. :mod:`django.contrib.redirects` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.sessions` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.sitemaps` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.sites` ~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.staticfiles` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * The :setting:`STATICFILES_DIRS` setting now supports :class:`pathlib.Path`. :mod:`django.contrib.syndication` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... Cache ~~~~~ * The :func:`~django.views.decorators.cache.cache_control` decorator and :func:`~django.utils.cache.patch_cache_control` method now support multiple field names in the ``no-cache`` directive for the ``Cache-Control`` header, according to :rfc:`7234#section-5.2.2.2`. * :meth:`~django.core.caches.cache.delete` now returns ``True`` if the key was successfully deleted, ``False`` otherwise. CSRF ~~~~ * ... Email ~~~~~ * The :setting:`EMAIL_FILE_PATH` setting, used by the :ref:`file email backend `, now supports :class:`pathlib.Path`. File Storage ~~~~~~~~~~~~ * ``FileSystemStorage.save()`` method now supports :class:`pathlib.Path`. File Uploads ~~~~~~~~~~~~ * ... Forms ~~~~~ * ... Generic Views ~~~~~~~~~~~~~ * ... Internationalization ~~~~~~~~~~~~~~~~~~~~ * ... Logging ~~~~~~~ * ... Management Commands ~~~~~~~~~~~~~~~~~~~ * ... Migrations ~~~~~~~~~~ * Migrations are now loaded also from directories without ``__init__.py`` files. Models ~~~~~~ * The new :class:`~django.db.models.functions.ExtractIsoWeekDay` function extracts ISO-8601 week days from :class:`~django.db.models.DateField` and :class:`~django.db.models.DateTimeField`, and the new :lookup:`iso_week_day` lookup allows querying by an ISO-8601 day of week. * :meth:`.QuerySet.explain` now supports: * ``TREE`` format on MySQL 8.0.16+, * ``analyze`` option on MySQL 8.0.18+ and MariaDB. * Added :class:`~django.db.models.PositiveBigIntegerField` which acts much like a :class:`~django.db.models.PositiveIntegerField` except that it only allows values under a certain (database-dependent) limit. Values from ``0`` to ``9223372036854775807`` are safe in all databases supported by Django. * The new :class:`~django.db.models.RESTRICT` option for :attr:`~django.db.models.ForeignKey.on_delete` argument of ``ForeignKey`` and ``OneToOneField`` emulates the behavior of the SQL constraint ``ON DELETE RESTRICT``. * :attr:`.CheckConstraint.check` now supports boolean expressions. Pagination ~~~~~~~~~~ * :class:`~django.core.paginator.Paginator` can now be iterated over to yield its pages. Requests and Responses ~~~~~~~~~~~~~~~~~~~~~~ * ... Serialization ~~~~~~~~~~~~~ * ... Signals ~~~~~~~ * ... Templates ~~~~~~~~~ * ... Tests ~~~~~ * :class:`~django.test.SimpleTestCase` now implements the ``debug()`` method to allow running a test without collecting the result and catching exceptions. This can be used to support running tests under a debugger. * The new :setting:`MIGRATE ` test database setting allows disabling of migrations during a test database creation. URLs ~~~~ * ... Utilities ~~~~~~~~~ * :func:`~django.utils.encoding.filepath_to_uri` now supports :class:`pathlib.Path`. * :func:`~django.utils.dateparse.parse_duration` now supports comma separators for decimal fractions in the ISO 8601 format. * :func:`~django.utils.dateparse.parse_datetime`, :func:`~django.utils.dateparse.parse_duration`, and :func:`~django.utils.dateparse.parse_time` now support comma separators for milliseconds. Validators ~~~~~~~~~~ * ... Miscellaneous ~~~~~~~~~~~~~ * The SQLite backend now supports :class:`pathlib.Path` for the ``NAME`` setting. * The ``settings.py`` generated by the :djadmin:`startproject` command now uses :class:`pathlib.Path` instead of :mod:`os.path` for building filesystem paths. .. _backwards-incompatible-3.1: Backwards incompatible changes in 3.1 ===================================== Database backend API -------------------- This section describes changes that may be needed in third-party database backends. * ``DatabaseOperations.fetch_returned_insert_columns()`` now requires an additional ``returning_params`` argument. Dropped support for MariaDB 10.1 -------------------------------- Upstream support for MariaDB 10.1 ends in October 2020. Django 3.1 supports MariaDB 10.2 and higher. Miscellaneous ------------- * The cache keys used by :ttag:`cache` and generated by :func:`~django.core.cache.utils.make_template_fragment_key` are different from the keys generated by older versions of Django. After upgrading to Django 3.1, the first request to any previously cached template fragment will be a cache miss. * The compatibility imports of ``django.core.exceptions.EmptyResultSet`` in ``django.db.models.query``, ``django.db.models.sql``, and ``django.db.models.sql.datastructures`` are removed. * The compatibility import of ``django.core.exceptions.FieldDoesNotExist`` in ``django.db.models.fields`` is removed. * The compatibility imports of ``django.forms.utils.pretty_name()`` and ``django.forms.boundfield.BoundField`` in ``django.forms.forms`` are removed. * The compatibility imports of ``Context``, ``ContextPopException``, and ``RequestContext`` in ``django.template.base`` are removed. * The compatibility import of ``django.contrib.admin.helpers.ACTION_CHECKBOX_NAME`` in ``django.contrib.admin`` is removed. * The :setting:`STATIC_URL` and :setting:`MEDIA_URL` settings set to relative paths are now prefixed by the server-provided value of ``SCRIPT_NAME`` (or ``/`` if not set). This change should not affect settings set to valid URLs or absolute paths. * :class:`~django.middleware.http.ConditionalGetMiddleware` no longer adds the ``ETag`` header to responses with an empty :attr:`~django.http.HttpResponse.content`. * ``django.utils.decorators.classproperty()`` decorator is moved to ``django.utils.functional.classproperty()``. * :tfilter:`floatformat` template filter now outputs (positive) ``0`` for negative numbers which round to zero. * :attr:`Meta.ordering ` and :attr:`Meta.unique_together ` options on models in ``django.contrib`` modules that were formerly tuples are now lists. .. _deprecated-features-3.1: Features deprecated in 3.1 ========================== Miscellaneous ------------- * ``PASSWORD_RESET_TIMEOUT_DAYS`` setting is deprecated in favor of :setting:`PASSWORD_RESET_TIMEOUT`. * The undocumented usage of the :lookup:`isnull` lookup with non-boolean values as the right-hand side is deprecated, use ``True`` or ``False`` instead. * The barely documented ``django.db.models.query_utils.InvalidQuery`` exception class is deprecated in favor of :class:`~django.core.exceptions.FieldDoesNotExist` and :class:`~django.core.exceptions.FieldError`. .. _removed-features-3.1: Features removed in 3.1 ======================= These features have reached the end of their deprecation cycle and are removed in Django 3.1. See :ref:`deprecated-features-2.2` for details on these changes, including how to remove usage of these features. * ``django.utils.timezone.FixedOffset`` is removed. * ``django.core.paginator.QuerySetPaginator`` is removed. * A model's ``Meta.ordering`` doesn't affect ``GROUP BY`` queries. * ``django.contrib.postgres.fields.FloatRangeField`` and ``django.contrib.postgres.forms.FloatRangeField`` are removed. * The ``FILE_CHARSET`` setting is removed. * ``django.contrib.staticfiles.storage.CachedStaticFilesStorage`` is removed. * The ``RemoteUserBackend.configure_user()`` method requires ``request`` as the first positional argument. * Support for ``SimpleTestCase.allow_database_queries`` and ``TransactionTestCase.multi_db`` is removed.