django1/docs/releases/3.2.txt

============================================
Django 3.2 release notes - UNDER DEVELOPMENT
============================================

*Expected April 2021*

Welcome to Django 3.2!

These release notes cover the :ref:`new features <whats-new-3.2>`, as well as
some :ref:`backwards incompatible changes <backwards-incompatible-3.2>` you'll
want to be aware of when upgrading from Django 3.1 or earlier. We've
:ref:`begun the deprecation process for some features
<deprecated-features-3.2>`.

See the :doc:`/howto/upgrade-version` guide if you're updating an existing
project.

Django 3.2 is designated as a :term:`long-term support release
<Long-term support release>`. It will receive security updates for at least
three years after its release. Support for the previous LTS, Django 2.2, will
end in April 2022.

Python compatibility
====================

Django 3.2 supports Python 3.6, 3.7, and 3.8. We **highly recommend** and only
officially support the latest release of each series.

.. _whats-new-3.2:

What's new in Django 3.2
========================

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
  216,000 to 260,000.

* The default variant for the Argon2 password hasher is changed to Argon2id.
  ``memory_cost`` and ``parallelism`` are increased to 102,400 and 8
  respectively to match the ``argon2-cffi`` defaults.

  Increasing the ``memory_cost`` pushes the required memory from 512 KB to 100
  MB. This is still rather conservative but can lead to problems in memory
  constrained environments. If this is the case, the existing hasher can be
  subclassed to override the defaults.

:mod:`django.contrib.contenttypes`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.gis`
~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.messages`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* The :class:`~django.contrib.postgres.operations.CreateExtension` operation
  now checks that the extension already exists in the database and skips the
  migration if so.

:mod:`django.contrib.postgres`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* The new :attr:`.ExclusionConstraint.include` attribute allows creating
  covering exclusion constraints on PostgreSQL 12+.

* The new :attr:`.ExclusionConstraint.opclasses` attribute allows setting
  PostgreSQL operator classes.

* The new :attr:`.JSONBAgg.ordering` attribute determines the ordering of the
  aggregated elements.

:mod:`django.contrib.redirects`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.sessions`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.sitemaps`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.sites`
~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.staticfiles`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

:mod:`django.contrib.syndication`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* ...

Cache
~~~~~

* ...

CSRF
~~~~

* ...

Email
~~~~~

* ...

Error Reporting
~~~~~~~~~~~~~~~

* ...

File Storage
~~~~~~~~~~~~

* ...

File Uploads
~~~~~~~~~~~~

* ...


Forms
~~~~~

* The new ``absolute_max`` argument for :func:`.formset_factory`,
  :func:`.inlineformset_factory`, and :func:`.modelformset_factory` allows
  customizing the maximum number of forms that can be instantiated when
  supplying ``POST`` data. See :ref:`formsets-absolute-max` for more details.

Generic Views
~~~~~~~~~~~~~

* ...

Internationalization
~~~~~~~~~~~~~~~~~~~~

* ...

Logging
~~~~~~~

* ...

Management Commands
~~~~~~~~~~~~~~~~~~~

* :djadmin:`loaddata` now supports fixtures stored in XZ archives (``.xz``) and
  LZMA archives (``.lzma``).

* :djadmin:`makemigrations` can now be called without an active database
  connection. In that case, check for a consistent migration history is
  skipped.

* :attr:`.BaseCommand.requires_system_checks` now supports specifying a list of
  tags. System checks registered in the chosen tags will be checked for errors
  prior to executing the command. In previous versions, either all or none
  of the system checks were performed.

Migrations
~~~~~~~~~~

* The new ``Operation.migration_name_fragment`` property allows providing a
  filename fragment that will be used to name a migration containing only that
  operation.

Models
~~~~~~

* The new ``no_key`` parameter for :meth:`.QuerySet.select_for_update()`,
  supported on PostgreSQL, allows acquiring weaker locks that don't block the
  creation of rows that reference locked rows through a foreign key.

* :class:`When() <django.db.models.expressions.When>` expression now allows
  using the ``condition`` argument with ``lookups``.

* The new :attr:`.Index.include` and :attr:`.UniqueConstraint.include`
  attributes allow creating covering indexes and covering unique constraints on
  PostgreSQL 11+.

* The new :attr:`.UniqueConstraint.opclasses` attribute allows setting
  PostgreSQL operator classes.

Requests and Responses
~~~~~~~~~~~~~~~~~~~~~~

* ...

Security
~~~~~~~~

* ...

Serialization
~~~~~~~~~~~~~

* The new :ref:`JSONL <serialization-formats-jsonl>` serializer allows using
  the JSON Lines format with :djadmin:`dumpdata` and :djadmin:`loaddata`. This
  can be useful for populating large databases because data is loaded line by
  line into memory, rather than being loaded all at once.

Signals
~~~~~~~

* ...

Templates
~~~~~~~~~

* ...

Tests
~~~~~

* Objects assigned to class attributes in :meth:`.TestCase.setUpTestData` are
  now isolated for each test method. Such objects are now required to support
  creating deep copies with :py:func:`copy.deepcopy`. Assigning objects which
  don't support ``deepcopy()`` is deprecated and will be removed in Django 4.1.

* :class:`~django.test.Client` now preserves the request query string when
  following 307 and 308 redirects.

URLs
~~~~

* ...

Utilities
~~~~~~~~~

* ...

Validators
~~~~~~~~~~

* ...

.. _backwards-incompatible-3.2:

Backwards incompatible changes in 3.2
=====================================

Database backend API
--------------------

This section describes changes that may be needed in third-party database
backends.

* The new ``DatabaseFeatures.introspected_field_types`` property replaces these
  features:

  * ``can_introspect_autofield``
  * ``can_introspect_big_integer_field``
  * ``can_introspect_binary_field``
  * ``can_introspect_decimal_field``
  * ``can_introspect_duration_field``
  * ``can_introspect_ip_address_field``
  * ``can_introspect_positive_integer_field``
  * ``can_introspect_small_integer_field``
  * ``can_introspect_time_field``
  * ``introspected_big_auto_field_type``
  * ``introspected_small_auto_field_type``
  * ``introspected_boolean_field_type``

* To enable support for covering indexes (:attr:`.Index.include`) and covering
  unique constraints (:attr:`.UniqueConstraint.include`), set
  ``DatabaseFeatures.supports_covering_indexes`` to ``True``.

:mod:`django.contrib.gis`
-------------------------

* Support for PostGIS 2.2 is removed.

Dropped support for PostgreSQL 9.5
----------------------------------

Upstream support for PostgreSQL 9.5 ends in February 2021. Django 3.2 supports
PostgreSQL 9.6 and higher.

Dropped support for MySQL 5.6
-----------------------------

The end of upstream support for MySQL 5.6 is April 2021. Django 3.2 supports
MySQL 5.7 and higher.

Miscellaneous
-------------

* The undocumented ``SpatiaLiteOperations.proj4_version()`` method is renamed
  to ``proj_version()``.

* Minified JavaScript files are no longer included with the admin. If you
  require these files to be minified, consider using a third party app or
  external build tool. The minified vendored JavaScript files packaged with the
  admin (e.g. :ref:`jquery.min.js <contrib-admin-jquery>`) are still included.

* :attr:`.ModelAdmin.prepopulated_fields` no longer strips English stop words,
  such as ``'a'`` or ``'an'``.

* :func:`~django.utils.text.slugify` now removes leading and trailing dashes
  and underscores.

* The :tfilter:`intcomma` and :tfilter:`intword` template filters no longer
  depend on the :setting:`USE_L10N` setting.

* Support for ``argon2-cffi`` < 19.1.0 is removed.

.. _deprecated-features-3.2:

Features deprecated in 3.2
==========================

Miscellaneous
-------------

* Assigning objects which don't support creating deep copies with
  :py:func:`copy.deepcopy` to class attributes in
  :meth:`.TestCase.setUpTestData` is deprecated.

* Using a boolean value in :attr:`.BaseCommand.requires_system_checks` is
  deprecated. Use ``'__all__'`` instead of ``True``, and ``[]`` (an empty list)
  instead of ``False``.