~~~~~~~~~~~~~~~~~~

* Updated Windows, macOS, and ``manylinux`` wheels to be compiled with
OpenSSL 1.1.1k.

.. _v3-4-6:

========================

*April 6, 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, 3.8, and 3.9. We **highly recommend** and
only officially support the latest release of each series.

.. _whats-new-3.2:

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

Automatic :class:`~django.apps.AppConfig` discovery
---------------------------------------------------

Most pluggable applications define an :class:`~django.apps.AppConfig` subclass
in an ``apps.py`` submodule. Many define a ``default_app_config`` variable
pointing to this class in their ``__init__.py``.

When the ``apps.py`` submodule exists and defines a single
:class:`~django.apps.AppConfig` subclass, Django now uses that configuration
automatically, so you can remove ``default_app_config``.

``default_app_config`` made it possible to declare only the application's path
in :setting:`INSTALLED_APPS` (e.g. ``'django.contrib.admin'``) rather than the
app config's path (e.g. ``'django.contrib.admin.apps.AdminConfig'``). It was
introduced for backwards-compatibility with the former style, with the intent
to switch the ecosystem to the latter, but the switch didn't happen.

With automatic ``AppConfig`` discovery, ``default_app_config`` is no longer
needed. As a consequence, it's deprecated.

See :ref:`configuring-applications-ref` for full details.

Customizing type of auto-created primary keys
---------------------------------------------

When defining a model, if no field in a model is defined with
:attr:`primary_key=True <django.db.models.Field.primary_key>` an implicit
primary key is added. The type of this implicit primary key can now be
controlled via the :setting:`DEFAULT_AUTO_FIELD` setting and
:attr:`AppConfig.default_auto_field <django.apps.AppConfig.default_auto_field>`
attribute. No more needing to override primary keys in all models.

Maintaining the historical behavior, the default value for
:setting:`DEFAULT_AUTO_FIELD` is :class:`~django.db.models.AutoField`. Starting
with 3.2 new projects are generated with :setting:`DEFAULT_AUTO_FIELD` set to
:class:`~django.db.models.BigAutoField`. Also, new apps are generated with
:attr:`AppConfig.default_auto_field <django.apps.AppConfig.default_auto_field>`
set to :class:`~django.db.models.BigAutoField`. In a future Django release the
default value of :setting:`DEFAULT_AUTO_FIELD` will be changed to
:class:`~django.db.models.BigAutoField`.

To avoid unwanted migrations in the future, either explicitly set
:setting:`DEFAULT_AUTO_FIELD` to :class:`~django.db.models.AutoField`::

 DEFAULT_AUTO_FIELD = 'django.db.models.AutoField'

or configure it on a per-app basis::

 from django.apps import AppConfig

 class MyAppConfig(AppConfig):
     default_auto_field = 'django.db.models.AutoField'
     name = 'my_app'

or on a per-model basis::

 from django.db import models

 class MyModel(models.Model):
     id = models.AutoField(primary_key=True)

In anticipation of the changing default, a system check will provide a warning
if you do not have an explicit setting for :setting:`DEFAULT_AUTO_FIELD`.

.. _new_functional_indexes:

Functional indexes
------------------

The new :attr:`*expressions <django.db.models.Index.expressions>` positional
argument of :class:`Index() <django.db.models.Index>` enables creating
functional indexes on expressions and database functions. For example::

 from django.db import models
 from django.db.models import F, Index, Value
 from django.db.models.functions import Lower, Upper


 class MyModel(models.Model):
     first_name = models.CharField(max_length=255)
     last_name = models.CharField(max_length=255)
     height = models.IntegerField()
     weight = models.IntegerField()

     class Meta:
         indexes = [
             Index(
                 Lower('first_name'),
                 Upper('last_name').desc(),
                 name='first_last_name_idx',
             ),
             Index(
                 F('height') / (F('weight') + Value(5)),
                 name='calc_idx',
             ),
         ]

Functional indexes are added to models using the
:attr:`Meta.indexes <django.db.models.Options.indexes>` option.

``pymemcache`` support
----------------------

The new ``django.core.cache.backends.memcached.PyMemcacheCache`` cache backend
allows using the pymemcache_ library for memcached. ``pymemcache`` 3.4.0 or
higher is required. For more details, see the :doc:`documentation on caching in
Django </topics/cache>`.

.. _pymemcache: https://pypi.org/project/pymemcache/

New decorators for the admin site
---------------------------------

The new :func:`~django.contrib.admin.display` decorator allows for easily
adding options to custom display functions that can be used with
:attr:`~django.contrib.admin.ModelAdmin.list_display` or
:attr:`~django.contrib.admin.ModelAdmin.readonly_fields`.

Likewise, the new :func:`~django.contrib.admin.action` decorator allows for
easily adding options to action functions that can be used with
:attr:`~django.contrib.admin.ModelAdmin.actions`.

Using the ``display`` decorator has the advantage that it is now
possible to use the ``property`` decorator when needing to specify attributes
on the custom method. Prior to this it was necessary to use the ``property()``
function instead after assigning the required attributes to the method.

Using decorators has the advantage that these options are more discoverable as
they can be suggested by completion utilities in code editors. They are merely
a convenience and still set the same attributes on the functions under the
hood.

Minor features
--------------

:mod:`django.contrib.admin`
~~~~~~~~~~~~~~~~~~~~~~~~~~~

* :attr:`.ModelAdmin.search_fields` now allows searching against quoted
phrases with spaces.

* Read-only related fields are now rendered as navigable links if target
models are registered in the admin.

* The admin now supports theming, and includes a dark theme that is enabled
according to browser settings. See :ref:`admin-theming` for more details.

* :attr:`.ModelAdmin.autocomplete_fields` now respects
:attr:`ForeignKey.to_field <django.db.models.ForeignKey.to_field>` and
:attr:`ForeignKey.limit_choices_to
<django.db.models.ForeignKey.limit_choices_to>` when searching a related
model.

* The admin now installs a final catch-all view that redirects unauthenticated
users to the login page, regardless of whether the URL is otherwise valid.
This protects against a potential model enumeration privacy issue.

Although not recommended, you may set the new
:attr:`.AdminSite.final_catch_all_view` to ``False`` to disable the
catch-all view.

: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.

* The default salt entropy for the Argon2, MD5, PBKDF2, SHA-1 password hashers
is increased from 71 to 128 bits.

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

* The new ``absolute_max`` argument for
:func:`~django.contrib.contenttypes.forms.generic_inlineformset_factory`
allows customizing the maximum number of forms that can be instantiated when
supplying ``POST`` data. See :ref:`formsets-absolute-max` for more details.

* The new ``can_delete_extra`` argument for
:func:`~django.contrib.contenttypes.forms.generic_inlineformset_factory`
allows removal of the option to delete extra forms. See
:attr:`~.BaseFormSet.can_delete_extra` for more information.

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

* The :meth:`.GDALRaster.transform` method now supports
:class:`~django.contrib.gis.gdal.SpatialReference`.

* The :class:`~django.contrib.gis.gdal.DataSource` class now supports
:class:`pathlib.Path`.

* The :class:`~django.contrib.gis.utils.LayerMapping` class now supports
:class:`pathlib.Path`.

: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.

* The new :attr:`.JSONBAgg.distinct` attribute determines if aggregated values
will be distinct.

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

* The new :class:`~django.contrib.postgres.operations.CreateCollation` and
:class:`~django.contrib.postgres.operations.RemoveCollation` operations
allow creating and dropping collations on PostgreSQL. See
:ref:`manage-postgresql-collations` for more details.

* Lookups for :class:`~django.contrib.postgres.fields.ArrayField` now allow
(non-nested) arrays containing expressions as right-hand sides.

* The new :class:`OpClass() <django.contrib.postgres.indexes.OpClass>`
expression allows creating functional indexes on expressions with a custom
operator class. See :ref:`new_functional_indexes` for more details.

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

* The new :class:`~django.contrib.sitemaps.Sitemap` attributes
:attr:`~django.contrib.sitemaps.Sitemap.alternates`,
:attr:`~django.contrib.sitemaps.Sitemap.languages` and
:attr:`~django.contrib.sitemaps.Sitemap.x_default` allow
generating sitemap *alternates* to localized versions of your pages.

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

* The new ``item_comments`` hook allows specifying a comments URL per feed
item.

Database backends
~~~~~~~~~~~~~~~~~

* Third-party database backends can now skip or mark as expected failures
tests in Django's test suite using the new
``DatabaseFeatures.django_test_skips`` and
``django_test_expected_failures`` attributes.

Decorators
~~~~~~~~~~

* The new :func:`~django.views.decorators.common.no_append_slash` decorator
allows individual views to be excluded from :setting:`APPEND_SLASH` URL
normalization.

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

* Custom :class:`~django.views.debug.ExceptionReporter` subclasses can now
define the :attr:`~django.views.debug.ExceptionReporter.html_template_path`
and :attr:`~django.views.debug.ExceptionReporter.text_template_path`
properties to override the templates used to render exception reports.

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

* The new :meth:`FileUploadHandler.upload_interrupted()
<django.core.files.uploadhandler.FileUploadHandler.upload_interrupted>`
callback allows handling interrupted 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.

* The new ``can_delete_extra`` argument for :func:`.formset_factory`,
:func:`.inlineformset_factory`, and :func:`.modelformset_factory` allows
removal of the option to delete extra forms. See
:attr:`~.BaseFormSet.can_delete_extra` for more information.

* :class:`~django.forms.formsets.BaseFormSet` now reports a user facing error,
rather than raising an exception, when the management form is missing or has
been tampered with. To customize this error message, pass the
``error_messages`` argument with the key ``'missing_management_form'`` when
instantiating the formset.

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

* The ``week_format`` attributes of
:class:`~django.views.generic.dates.WeekMixin` and
:class:`~django.views.generic.dates.WeekArchiveView` now support the
``'%V'`` ISO 8601 week format.

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

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

* :djadmin:`dumpdata` now can compress data in the ``bz2``, ``gz``, ``lzma``,
or ``xz`` formats.

* :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.

* Support for colored terminal output on Windows is updated. Various modern
terminal environments are automatically detected, and the options for
enabling support in other cases are improved. See :ref:`syntax-coloring` for
more details.

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.

* Migrations now support serialization of pure and concrete path objects from
:mod:`pathlib`, and :class:`os.PathLike` instances.

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.

* The :meth:`.QuerySet.update` method now respects the ``order_by()`` clause
on MySQL and MariaDB.

* :class:`FilteredRelation() <django.db.models.FilteredRelation>` now supports
nested relations.

* The ``of`` argument of :meth:`.QuerySet.select_for_update()` is now allowed
on MySQL 8.0.1+.

* :class:`Value() <django.db.models.Value>` expression now
automatically resolves its ``output_field`` to the appropriate
:class:`Field <django.db.models.Field>` subclass based on the type of
its provided ``value`` for :py:class:`bool`, :py:class:`bytes`,
:py:class:`float`, :py:class:`int`, :py:class:`str`,
:py:class:`datetime.date`, :py:class:`datetime.datetime`,
:py:class:`datetime.time`, :py:class:`datetime.timedelta`,
:py:class:`decimal.Decimal`, and :py:class:`uuid.UUID` instances. As a
consequence, resolving an ``output_field`` for database functions and
combined expressions may now crash with mixed types when using ``Value()``.
You will need to explicitly set the ``output_field`` in such cases.

* The new :meth:`.QuerySet.alias` method allows creating reusable aliases for
expressions that don't need to be selected but are used for filtering,
ordering, or as a part of complex expressions.

* The new :class:`~django.db.models.functions.Collate` function allows
filtering and ordering by specified database collations.

* The ``field_name`` argument of :meth:`.QuerySet.in_bulk()` now accepts
distinct fields if there's only one field specified in
:meth:`.QuerySet.distinct`.

* The new ``tzinfo`` parameter of the
:class:`~django.db.models.functions.TruncDate` and
:class:`~django.db.models.functions.TruncTime` database functions allows
truncating datetimes in a specific timezone.

* The new ``db_collation`` argument for
:attr:`CharField <django.db.models.CharField.db_collation>` and
:attr:`TextField <django.db.models.TextField.db_collation>` allows setting a
database collation for the field.

* Added the :class:`~django.db.models.functions.Random` database function.

* :ref:`aggregation-functions`, :class:`F() <django.db.models.F>`,
:class:`OuterRef() <django.db.models.OuterRef>`, and other expressions now
allow using transforms. See :ref:`using-transforms-in-expressions` for
details.

* The new ``durable`` argument for :func:`~django.db.transaction.atomic`
guarantees that changes made in the atomic block will be committed if the
block exits without errors. A nested atomic block marked as durable will
raise a ``RuntimeError``.

* Added the :class:`~django.db.models.functions.JSONObject` database function.

Pagination
~~~~~~~~~~

* The new :meth:`django.core.paginator.Paginator.get_elided_page_range` method
allows generating a page range with some of the values elided. If there are
a large number of pages, this can be helpful for generating a reasonable
number of page links in a template.

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

* Response headers are now stored in :attr:`.HttpResponse.headers`. This can
be used instead of the original dict-like interface of ``HttpResponse``
objects. Both interfaces will continue to be supported. See
:ref:`setting-header-fields` for details.

* The new ``headers`` parameter of :class:`~django.http.HttpResponse`,
:class:`~django.template.response.SimpleTemplateResponse`, and
:class:`~django.template.response.TemplateResponse` allows setting response
:attr:`~django.http.HttpResponse.headers` on instantiation.

Security
~~~~~~~~

* The :setting:`SECRET_KEY` setting is now checked for a valid value upon
first access, rather than when settings are first loaded. This enables
running management commands that do not rely on the ``SECRET_KEY`` without
needing to provide a value. As a consequence of this, calling
:func:`~django.conf.settings.configure` without providing a valid
``SECRET_KEY``, and then going on to access ``settings.SECRET_KEY`` will now
raise an :exc:`~django.core.exceptions.ImproperlyConfigured` exception.

* The new ``Signer.sign_object()`` and ``Signer.unsign_object()`` methods
allow signing complex data structures. See :ref:`signing-complex-data` for
more details.

Also, :func:`signing.dumps() <django.core.signing.dumps>` and
:func:`~django.core.signing.loads` become shortcuts for
:meth:`.TimestampSigner.sign_object` and
:meth:`~.TimestampSigner.unsign_object`.

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
~~~~~~~

* :meth:`Signal.send_robust() <django.dispatch.Signal.send_robust>` now logs
exceptions.

Templates
~~~~~~~~~

* :tfilter:`floatformat` template filter now allows using the ``g`` suffix to
force grouping by the :setting:`THOUSAND_SEPARATOR` for the active locale.

* Templates cached with :ref:`Cached template loaders<template-loaders>` are
now correctly reloaded in development.

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.runner.DiscoverRunner` now enables
:py:mod:`faulthandler` by default. This can be disabled by using the
:option:`test --no-faulthandler` option.

* :class:`~django.test.runner.DiscoverRunner` and the
:djadmin:`test` management command can now track timings, including database
setup and total run time. This can be enabled by using the :option:`test
--timing` option.

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

* The new :meth:`.TestCase.captureOnCommitCallbacks` method captures callback
functions passed to :func:`transaction.on_commit()
<django.db.transaction.on_commit>` in a list. This allows you to test such
callbacks without using the slower :class:`.TransactionTestCase`.

* :meth:`.TransactionTestCase.assertQuerysetEqual` now supports direct
comparison against another queryset rather than being restricted to
comparison against a list of string representations of objects when using
the default value for the ``transform`` argument.

Utilities
~~~~~~~~~

* The new ``depth`` parameter of ``django.utils.timesince.timesince()`` and
``django.utils.timesince.timeuntil()`` functions allows specifying the
number of adjacent time units to return.

Validators
~~~~~~~~~~

* Built-in validators now include the provided value in the ``params``
argument of a raised :exc:`~django.core.exceptions.ValidationError`. This
allows custom error messages to use the ``%(value)s`` placeholder.

* The :class:`.ValidationError` equality operator now ignores ``messages`` and
``params`` ordering.

.. _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``.

* Third-party database backends must implement support for column database
collations on ``CharField``\s and ``TextField``\s or set
``DatabaseFeatures.supports_collation_on_charfield`` and
``DatabaseFeatures.supports_collation_on_textfield`` to ``False``. If
non-deterministic collations are not supported, set
``supports_non_deterministic_collations`` to ``False``.

* ``DatabaseOperations.random_function_sql()`` is removed in favor of the new
:class:`~django.db.models.functions.Random` database function.

* ``DatabaseOperations.date_trunc_sql()`` and
``DatabaseOperations.time_trunc_sql()`` now take the optional ``tzname``
argument in order to truncate in a specific timezone.

* ``DatabaseClient.runshell()`` now gets arguments and an optional dictionary
with environment variables to the underlying command-line client from
``DatabaseClient.settings_to_cmd_args_env()`` method. Third-party database
backends must implement ``DatabaseClient.settings_to_cmd_args_env()`` or
override ``DatabaseClient.runshell()``.

* Third-party database backends must implement support for functional indexes
(:attr:`.Index.expressions`) or set
``DatabaseFeatures.supports_expression_indexes`` to ``False``. If
``COLLATE`` is not a part of the ``CREATE INDEX`` statement, set
``DatabaseFeatures.collate_as_index_expression`` to ``True``.

:mod:`django.contrib.admin`
---------------------------

* Pagination links in the admin are now 1-indexed instead of 0-indexed, i.e.
the query string for the first page is ``?p=1`` instead of ``?p=0``.

* The new admin catch-all view will break URL patterns routed after the admin
URLs and matching the admin URL prefix. You can either adjust your URL
ordering or, if necessary, set :attr:`AdminSite.final_catch_all_view
<django.contrib.admin.AdminSite.final_catch_all_view>` to ``False``,
disabling the catch-all view. See :ref:`whats-new-3.2` for more details.

* 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'``.

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

* Support for PostGIS 2.2 is removed.

* The Oracle backend now clones polygons (and geometry collections containing
polygons) before reorienting them and saving them to the database. They are
no longer mutated in place. You might notice this if you use the polygons
after a model is saved.

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
-------------

* Django now supports non-``pytz`` time zones, such as Python 3.9+'s
:mod:`zoneinfo` module and its backport.

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

* :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.

* The cache keys no longer includes the language when internationalization is
disabled (``USE_I18N = False``) and localization is enabled
(``USE_L10N = True``). After upgrading to Django 3.2 in such configurations,
the first request to any previously cached value will be a cache miss.

* ``ForeignKey.validate()`` now uses
:attr:`~django.db.models.Model._base_manager` rather than
:attr:`~django.db.models.Model._default_manager` to check that related
instances exist.

* When an application defines an :class:`~django.apps.AppConfig` subclass in
an ``apps.py`` submodule, Django now uses this configuration automatically,
even if it isn't enabled with ``default_app_config``. Set
``default = False`` in the :class:`~django.apps.AppConfig` subclass if you
need to prevent this behavior. See :ref:`whats-new-3.2` for more details.

* Instantiating an abstract model now raises ``TypeError``.

* Keyword arguments to :func:`~django.test.utils.setup_databases` are now
keyword-only.

* The undocumented ``django.utils.http.limited_parse_qsl()`` function is
removed. Please use :func:`urllib.parse.parse_qsl` instead.

* ``django.test.utils.TestContextDecorator`` now uses
:py:meth:`~unittest.TestCase.addCleanup` so that cleanups registered in the
:py:meth:`~unittest.TestCase.setUp` method are called before
``TestContextDecorator.disable()``.

* ``SessionMiddleware`` now raises a
:exc:`~django.contrib.sessions.exceptions.SessionInterrupted` exception
instead of :exc:`~django.core.exceptions.SuspiciousOperation` when a session
is destroyed in a concurrent request.

* The :class:`django.db.models.Field` equality operator now correctly
distinguishes inherited field instances across models. Additionally, the
ordering of such fields is now defined.

* The undocumented ``django.core.files.locks.lock()`` function now returns
``False`` if the file cannot be locked, instead of raising
:exc:`BlockingIOError`.

* The password reset mechanism now invalidates tokens when the user email is
changed.

* :djadmin:`makemessages` command no longer processes invalid locales
specified using :option:`makemessages --locale` option, when they contain
hyphens (``'-'``).

* The ``django.contrib.auth.forms.ReadOnlyPasswordHashField`` form field is
now :attr:`~django.forms.Field.disabled` by default. Therefore
``UserChangeForm.clean_password()`` is no longer required to return the
initial value.

* The ``cache.get_many()``, ``get_or_set()``, ``has_key()``, ``incr()``,
``decr()``, ``incr_version()``, and ``decr_version()`` cache operations now
correctly handle ``None`` stored in the cache, in the same way as any other
value, instead of behaving as though the key didn't exist.

Due to a ``python-memcached`` limitation, the previous behavior is kept for
the deprecated ``MemcachedCache`` backend.

* The minimum supported version of SQLite is increased from 3.8.3 to 3.9.0.

* :class:`~django.contrib.messages.storage.cookie.CookieStorage` now stores
messages in the :rfc:`6265` compliant format. Support for cookies that use
the old format remains until Django 4.1.

* The minimum supported version of ``asgiref`` is increased from 3.2.10 to
3.3.2.

.. _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``.

* The ``whitelist`` argument and ``domain_whitelist`` attribute of
:class:`~django.core.validators.EmailValidator` are deprecated. Use
``allowlist`` instead of ``whitelist``, and ``domain_allowlist`` instead of
``domain_whitelist``. You may need to rename ``whitelist`` in existing
migrations.

* The ``default_app_config`` application configuration variable is deprecated,
due to the now automatic ``AppConfig`` discovery. See :ref:`whats-new-3.2`
for more details.

* Automatically calling ``repr()`` on a queryset in
``TransactionTestCase.assertQuerysetEqual()``, when compared to string
values, is deprecated. If you need the previous behavior, explicitly set
``transform`` to ``repr``.

* The ``django.core.cache.backends.memcached.MemcachedCache`` backend is
deprecated as ``python-memcached`` has some problems and seems to be
unmaintained. Use ``django.core.cache.backends.memcached.PyMemcacheCache``
or ``django.core.cache.backends.memcached.PyLibMCCache`` instead.

* The format of messages used by
``django.contrib.messages.storage.cookie.CookieStorage`` is different from
the format generated by older versions of Django. Support for the old format
remains until Django 4.1.


==========================

===================

- document WEB_CONCURRENCY is set by, at least, Heroku
- capture peername from accept: Avoid calls to getpeername by capturing the peer name returned by
accept
- log a warning when a worker was terminated due to a signal
- fix tornado usage with latest versions of Django 
- add support for python -m gunicorn
- fix systemd socket activation example
- allows to set wsgi application in configg file using `wsgi_app`
- document `--timeout = 0`
- always close a connection when the number of requests exceeds the max requests
- Disable keepalive during graceful shutdown
- kill tasks in the gthread workers during upgrade
- fix latency in gevent worker when accepting new requests
- fix file watcher: handle errors when new worker reboot and ensure the list of files is kept
- document the default name and path of the configuration file
- document how variable impact configuration
- document the `$PORT` environment variable
- added milliseconds option to request_time in access_log
- added PIP requirements to be used for example
- remove version from the Server header
- fix sendfile: use `socket.sendfile` instead of `os.sendfile`
- reloader: use  absolute path to prevent empty to prevent0 `InotifyError` when a file 
is added to the working directory
- Add --print-config option to print the resolved settings at startup.
- remove the `--log-dict-config` CLI flag because it never had a working format
(the `logconfig_dict` setting in configuration files continues to work)


** Breaking changes **

- minimum version is Python 3.5
- remove version from the Server header 

** Documentation **



** Others **

- miscellaneous changes in the code base to be a better citizen with Python 3
- remove dead code
- fix documentation generation