============================================ Django 2.2 release notes - UNDER DEVELOPMENT ============================================ *Expected April 2019* Welcome to Django 2.2! These release notes cover the :ref:`new features <whats-new-2.2>`, as well as some :ref:`backwards incompatible changes <backwards-incompatible-2.2>` you'll want to be aware of when upgrading from Django 2.1 or earlier. We've :ref:`begun the deprecation process for some features <deprecated-features-2.2>`. See the :doc:`/howto/upgrade-version` guide if you're updating an existing project. Django 2.2 is designated as a :term:`long-term support release`. It will receive security updates for at least three years after its release. Support for the previous LTS, Django 1.11, will end in April 2020. Python compatibility ==================== Django 2.2 supports Python 3.5, 3.6, and 3.7. We **highly recommend** and only officially support the latest release of each series. .. _whats-new-2.2: What's new in Django 2.2 ======================== Check Constraints ----------------- The new :class:`~django.db.models.CheckConstraint` class enables adding custom database constraints. Constraints are added to models using the :attr:`Meta.constraints <django.db.models.Options.constraints>` option. Minor features -------------- :mod:`django.contrib.admin` ~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.admindocs` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.auth` ~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.contenttypes` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.gis` ~~~~~~~~~~~~~~~~~~~~~~~~~ * Added Oracle support for the :class:`~django.contrib.gis.db.models.functions.Envelope` function. * Added SpatiaLite support for the :lookup:`coveredby` and :lookup:`covers` lookups. :mod:`django.contrib.messages` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.postgres` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * The new ``ordering`` argument for :class:`~django.contrib.postgres.aggregates.ArrayAgg` and :class:`~django.contrib.postgres.aggregates.StringAgg` determines the ordering of the aggregated elements. * The new :class:`~django.contrib.postgres.indexes.BTreeIndex`, :class:`~django.contrib.postgres.indexes.HashIndex` and :class:`~django.contrib.postgres.indexes.SpGistIndex` classes allow creating ``B-Tree``, ``hash``, and ``SP-GiST`` indexes in the database. * :class:`~django.contrib.postgres.indexes.BrinIndex` now has the ``autosummarize`` parameter. :mod:`django.contrib.redirects` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.sessions` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.sitemaps` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.sites` ~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... :mod:`django.contrib.staticfiles` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * Added path matching to the :option:`collectstatic --ignore` option so that patterns like ``/vendor/*.js`` can be used. :mod:`django.contrib.syndication` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * ... Cache ~~~~~ * ... CSRF ~~~~ * ... Database backends ~~~~~~~~~~~~~~~~~ * Added result streaming for :meth:`.QuerySet.iterator` on SQLite. Email ~~~~~ * ... File Storage ~~~~~~~~~~~~ * ... File Uploads ~~~~~~~~~~~~ * ... Forms ~~~~~ * ... Generic Views ~~~~~~~~~~~~~ * ... Internationalization ~~~~~~~~~~~~~~~~~~~~ * ... Management Commands ~~~~~~~~~~~~~~~~~~~ * ... Migrations ~~~~~~~~~~ * The new :option:`migrate --plan` option prints the list of migration operations that will be performed. Models ~~~~~~ * Added support for PostgreSQL operator classes (:attr:`.Index.opclasses`). * Added many :ref:`math database functions <math-functions>`. * Setting the new ``ignore_conflicts`` parameter of :meth:`.QuerySet.bulk_create` to ``True`` tells the database to ignore failure to insert rows that fail uniqueness constraints or other checks. * The new :class:`~django.db.models.functions.ExtractIsoYear` function extracts ISO-8601 week-numbering years from :class:`~django.db.models.DateField` and :class:`~django.db.models.DateTimeField`, and the new :lookup:`iso_year` lookup allows querying by an ISO-8601 week-numbering year. Requests and Responses ~~~~~~~~~~~~~~~~~~~~~~ * ... Serialization ~~~~~~~~~~~~~ * You can now deserialize data using natural keys containing :ref:`forward references <natural-keys-and-forward-references>` by passing ``handle_forward_references=True`` to ``serializers.deserialize()``. Additionally, :djadmin:`loaddata` handles forward references automatically. Signals ~~~~~~~ * ... Templates ~~~~~~~~~ * ... Tests ~~~~~ * The new :meth:`.SimpleTestCase.assertURLEqual` assertion checks for a given URL, ignoring the ordering of the query string. :meth:`~.SimpleTestCase.assertRedirects` uses the new assertion. * The test :class:`~.django.test.Client` now supports automatic JSON serialization of list and tuple ``data`` when ``content_type='application/json'``. URLs ~~~~ * ... Validators ~~~~~~~~~~ * ... .. _backwards-incompatible-2.2: Backwards incompatible changes in 2.2 ===================================== Database backend API -------------------- * Third-party database backends must implement support for table check constraints or set ``DatabaseFeatures.supports_table_check_constraints`` to ``False``. * Third party database backends must implement support for ignoring constraints or uniqueness errors while inserting or set ``DatabaseFeatures.supports_ignore_conflicts`` to ``False``. :mod:`django.contrib.gis` ------------------------- * Support for GDAL 1.9 and 1.10 is dropped. * To improve readability, the ``UUIDField`` form field now displays values with dashes, e.g. ``550e8400-e29b-41d4-a716-446655440000`` instead of ``550e8400e29b41d4a716446655440000``. Miscellaneous ------------- * On SQLite, ``PositiveIntegerField`` and ``PositiveSmallIntegerField`` now include a check constraint to prevent negative values in the database. If you have existing invalid data and run a migration that recreates a table, you'll see ``CHECK constraint failed``. * For consistency with WSGI servers, the test client now sets the ``Content-Length`` header to a string rather than an integer. * The return value of :func:`django.utils.text.slugify` is no longer marked as HTML safe. * The default truncation character used by the :tfilter:`urlizetrunc`, :tfilter:`truncatechars`, :tfilter:`truncatechars_html`, :tfilter:`truncatewords`, and :tfilter:`truncatewords_html` template filters is now the real ellipsis character (``…``) instead of 3 dots. You may have to adapt some test output comparisons. .. _deprecated-features-2.2: Features deprecated in 2.2 ========================== Miscellaneous ------------- * ``django.utils.timezone.FixedOffset`` is deprecated in favor of :class:`datetime.timezone`. * The undocumented ``QuerySetPaginator`` alias of ``django.core.paginator.Paginator`` is deprecated.