mirror of https://github.com/django/django.git
578 lines
17 KiB
Plaintext
578 lines
17 KiB
Plaintext
============================================
|
|
Django 4.0 release notes - UNDER DEVELOPMENT
|
|
============================================
|
|
|
|
*Expected December 2021*
|
|
|
|
Welcome to Django 4.0!
|
|
|
|
These release notes cover the :ref:`new features <whats-new-4.0>`, as well as
|
|
some :ref:`backwards incompatible changes <backwards-incompatible-4.0>` you'll
|
|
want to be aware of when upgrading from Django 3.2 or earlier. We've
|
|
:ref:`begun the deprecation process for some features
|
|
<deprecated-features-4.0>`.
|
|
|
|
See the :doc:`/howto/upgrade-version` guide if you're updating an existing
|
|
project.
|
|
|
|
Python compatibility
|
|
====================
|
|
|
|
Django 4.0 supports Python 3.8, 3.9, and 3.10. We **highly recommend** and only
|
|
officially support the latest release of each series.
|
|
|
|
The Django 3.2.x series is the last to support Python 3.6 and 3.7.
|
|
|
|
.. _whats-new-4.0:
|
|
|
|
What's new in Django 4.0
|
|
========================
|
|
|
|
Functional unique constraints
|
|
-----------------------------
|
|
|
|
The new :attr:`*expressions <django.db.models.UniqueConstraint.expressions>`
|
|
positional argument of
|
|
:class:`UniqueConstraint() <django.db.models.UniqueConstraint>` enables
|
|
creating functional unique constraints on expressions and database functions.
|
|
For example::
|
|
|
|
from django.db import models
|
|
from django.db.models import UniqueConstraint
|
|
from django.db.models.functions import Lower
|
|
|
|
|
|
class MyModel(models.Model):
|
|
first_name = models.CharField(max_length=255)
|
|
last_name = models.CharField(max_length=255)
|
|
|
|
class Meta:
|
|
indexes = [
|
|
UniqueConstraint(
|
|
Lower('first_name'),
|
|
Lower('last_name').desc(),
|
|
name='first_last_name_unique',
|
|
),
|
|
]
|
|
|
|
Functional unique constraints are added to models using the
|
|
:attr:`Meta.constraints <django.db.models.Options.constraints>` option.
|
|
|
|
Minor features
|
|
--------------
|
|
|
|
:mod:`django.contrib.admin`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* The ``admin/base.html`` template now has a new block ``header`` which
|
|
contains the admin site header.
|
|
|
|
* The new :meth:`.ModelAdmin.get_formset_kwargs` method allows customizing the
|
|
keyword arguments passed to the constructor of a formset.
|
|
|
|
* The navigation sidebar now has a quick filter toolbar.
|
|
|
|
* The new context variable ``model`` which contains the model class for each
|
|
model is added to the :meth:`.AdminSite.each_context` method.
|
|
|
|
* The new :attr:`.ModelAdmin.search_help_text` attribute allows specifying a
|
|
descriptive text for the search box.
|
|
|
|
:mod:`django.contrib.admindocs`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* The admindocs now allows esoteric setups where :setting:`ROOT_URLCONF` is not
|
|
a string.
|
|
|
|
* The model section of the ``admindocs`` now shows cached properties.
|
|
|
|
:mod:`django.contrib.auth`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* The default iteration count for the PBKDF2 password hasher is increased from
|
|
260,000 to 320,000.
|
|
|
|
* The new
|
|
:attr:`LoginView.next_page <django.contrib.auth.views.LoginView.next_page>`
|
|
attribute and
|
|
:meth:`~django.contrib.auth.views.LoginView.get_default_redirect_url` method
|
|
allow customizing the redirect after login.
|
|
|
|
:mod:`django.contrib.contenttypes`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
:mod:`django.contrib.gis`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* Added support for SpatiaLite 5.
|
|
|
|
* :class:`~django.contrib.gis.gdal.GDALRaster` now allows creating rasters in
|
|
any GDAL virtual filesystem.
|
|
|
|
:mod:`django.contrib.messages`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
:mod:`django.contrib.postgres`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* The PostgreSQL backend now supports connecting by a service name. See
|
|
:ref:`postgresql-connection-settings` for more details.
|
|
|
|
:mod:`django.contrib.redirects`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
:mod:`django.contrib.sessions`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
:mod:`django.contrib.sitemaps`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
:mod:`django.contrib.sites`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
:mod:`django.contrib.staticfiles`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* :class:`~django.contrib.staticfiles.storage.ManifestStaticFilesStorage` now
|
|
replaces paths to JavaScript source map references with their hashed
|
|
counterparts.
|
|
|
|
* :class:`~django.contrib.staticfiles.storage.ManifestStaticFilesStorage` now
|
|
replaces paths to JavaScript modules in ``import`` and ``export`` statements
|
|
with their hashed counterparts.
|
|
|
|
:mod:`django.contrib.syndication`
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Cache
|
|
~~~~~
|
|
|
|
* ...
|
|
|
|
CSRF
|
|
~~~~
|
|
|
|
* CSRF protection now consults the ``Origin`` header, if present. To facilitate
|
|
this, :ref:`some changes <csrf-trusted-origins-changes-4.0>` to the
|
|
:setting:`CSRF_TRUSTED_ORIGINS` setting are required.
|
|
|
|
Decorators
|
|
~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Email
|
|
~~~~~
|
|
|
|
* ...
|
|
|
|
Error Reporting
|
|
~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
File Storage
|
|
~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
File Uploads
|
|
~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Forms
|
|
~~~~~
|
|
|
|
* :class:`~django.forms.ModelChoiceField` now includes the provided value in
|
|
the ``params`` argument of a raised
|
|
:exc:`~django.core.exceptions.ValidationError` for the ``invalid_choice``
|
|
error message. This allows custom error messages to use the ``%(value)s``
|
|
placeholder.
|
|
|
|
Generic Views
|
|
~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Internationalization
|
|
~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Logging
|
|
~~~~~~~
|
|
|
|
* ...
|
|
|
|
Management Commands
|
|
~~~~~~~~~~~~~~~~~~~
|
|
|
|
* The :djadmin:`runserver` management command now supports the
|
|
:option:`--skip-checks` option.
|
|
|
|
* On PostgreSQL, :djadmin:`dbshell` now supports specifying a password file.
|
|
|
|
Migrations
|
|
~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Models
|
|
~~~~~~
|
|
|
|
* New :meth:`QuerySet.contains(obj) <.QuerySet.contains>` method returns
|
|
whether the queryset contains the given object. This tries to perform the
|
|
query in the simplest and fastest way possible.
|
|
|
|
* The new ``precision`` argument of the
|
|
:class:`Round() <django.db.models.functions.Round>` database function allows
|
|
specifying the number of decimal places after rounding.
|
|
|
|
* :meth:`.QuerySet.bulk_create` now sets the primary key on objects when using
|
|
SQLite 3.35+.
|
|
|
|
* :class:`~django.db.models.DurationField` now supports multiplying and
|
|
dividing by scalar values on SQLite.
|
|
|
|
Requests and Responses
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* The :class:`~django.middleware.security.SecurityMiddleware` now adds the
|
|
:ref:`Cross-Origin Opener Policy <cross-origin-opener-policy>` header with a
|
|
value of ``'same-origin'`` to prevent cross-origin popups from sharing the
|
|
same browsing context. You can prevent this header from being added by
|
|
setting the :setting:`SECURE_CROSS_ORIGIN_OPENER_POLICY` setting to ``None``.
|
|
|
|
Security
|
|
~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Serialization
|
|
~~~~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Signals
|
|
~~~~~~~
|
|
|
|
* The new ``stdout`` argument for :func:`~django.db.models.signals.pre_migrate`
|
|
and :func:`~django.db.models.signals.post_migrate` signals allows redirecting
|
|
output to a stream-like object. It should be preferred over
|
|
:py:data:`sys.stdout` and :py:func:`print` when emitting verbose output in
|
|
order to allow proper capture when testing.
|
|
|
|
Templates
|
|
~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Tests
|
|
~~~~~
|
|
|
|
* The new ``serialized_aliases`` argument of
|
|
:func:`django.test.utils.setup_databases` determines which
|
|
:setting:`DATABASES` aliases test databases should have their state
|
|
serialized to allow usage of the
|
|
:ref:`serialized_rollback <test-case-serialized-rollback>` feature.
|
|
|
|
* Django test runner now supports a :option:`--buffer <test --buffer>` option
|
|
with parallel tests.
|
|
|
|
* The new :meth:`.DiscoverRunner.log` method allows customizing the way
|
|
messages are logged.
|
|
|
|
URLs
|
|
~~~~
|
|
|
|
* ...
|
|
|
|
Utilities
|
|
~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
Validators
|
|
~~~~~~~~~~
|
|
|
|
* ...
|
|
|
|
.. _backwards-incompatible-4.0:
|
|
|
|
Backwards incompatible changes in 4.0
|
|
=====================================
|
|
|
|
Database backend API
|
|
--------------------
|
|
|
|
This section describes changes that may be needed in third-party database
|
|
backends.
|
|
|
|
* ``DatabaseOperations.year_lookup_bounds_for_date_field()`` and
|
|
``year_lookup_bounds_for_datetime_field()`` methods now take the optional
|
|
``iso_year`` argument in order to support bounds for ISO-8601 week-numbering
|
|
years.
|
|
|
|
* The second argument of ``DatabaseSchemaEditor._unique_sql()`` and
|
|
``_create_unique_sql()`` methods is now fields instead of columns.
|
|
|
|
:mod:`django.contrib.gis`
|
|
-------------------------
|
|
|
|
* Support for PostGIS 2.3 is removed.
|
|
|
|
* Support for GDAL 2.0 and GEOS 3.5 is removed.
|
|
|
|
Dropped support for PostgreSQL 9.6
|
|
----------------------------------
|
|
|
|
Upstream support for PostgreSQL 9.6 ends in November 2021. Django 4.0 supports
|
|
PostgreSQL 10 and higher.
|
|
|
|
Dropped support for Oracle 12.2 and 18c
|
|
---------------------------------------
|
|
|
|
Upstream support for Oracle 12.2 ends in March 2022 and for Oracle 18c it ends
|
|
in June 2021. Django 3.2 will be supported until April 2024. Django 4.0
|
|
officially supports Oracle 19c.
|
|
|
|
.. _csrf-trusted-origins-changes-4.0:
|
|
|
|
``CSRF_TRUSTED_ORIGINS`` changes
|
|
--------------------------------
|
|
|
|
Format change
|
|
~~~~~~~~~~~~~
|
|
|
|
Values in the :setting:`CSRF_TRUSTED_ORIGINS` setting must include the scheme
|
|
(e.g. ``'http://'`` or ``'https://'``) instead of only the hostname.
|
|
|
|
Also, values that started with a dot, must now also include an asterisk before
|
|
the dot. For example, change ``'.example.com'`` to ``'https://*.example.com'``.
|
|
|
|
A system check detects any required changes.
|
|
|
|
Configuring it may now be required
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
As CSRF protection now consults the ``Origin`` header, you may need to set
|
|
:setting:`CSRF_TRUSTED_ORIGINS`, particularly if you allow requests from
|
|
subdomains by setting :setting:`CSRF_COOKIE_DOMAIN` (or
|
|
:setting:`SESSION_COOKIE_DOMAIN` if :setting:`CSRF_USE_SESSIONS` is enabled) to
|
|
a value starting with a dot.
|
|
|
|
``SecurityMiddleware`` no longer sets the ``X-XSS-Protection`` header
|
|
---------------------------------------------------------------------
|
|
|
|
The :class:`~django.middleware.security.SecurityMiddleware` no longer sets the
|
|
``X-XSS-Protection`` header if the ``SECURE_BROWSER_XSS_FILTER`` setting is
|
|
``True``. The setting is removed.
|
|
|
|
Most modern browsers don't honor the ``X-XSS-Protection`` HTTP header. You can
|
|
use Content-Security-Policy_ without allowing ``'unsafe-inline'`` scripts
|
|
instead.
|
|
|
|
If you want to support legacy browsers and set the header, use this line in a
|
|
custom middleware::
|
|
|
|
response.headers.setdefault('X-XSS-Protection', '1; mode=block')
|
|
|
|
.. _Content-Security-Policy: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
|
|
|
|
Migrations autodetector changes
|
|
-------------------------------
|
|
|
|
The migrations autodetector now uses model states instead of model classes.
|
|
Also, migration operations for ``ForeignKey`` and ``ManyToManyField`` fields no
|
|
longer specify attributes which were not passed to the fields during
|
|
initialization.
|
|
|
|
As a side-effect, running ``makemigrations`` might generate no-op
|
|
``AlterField`` operations for ``ManyToManyField`` and ``ForeignKey`` fields in
|
|
some cases.
|
|
|
|
Miscellaneous
|
|
-------------
|
|
|
|
* Support for ``cx_Oracle`` < 7.0 is removed.
|
|
|
|
* To allow serving a Django site on a subpath without changing the value of
|
|
:setting:`STATIC_URL`, the leading slash is removed from that setting (now
|
|
``'static/'``) in the default :djadmin:`startproject` template.
|
|
|
|
* The :class:`~django.contrib.admin.AdminSite` method for the admin ``index``
|
|
view is no longer decorated with ``never_cache`` when accessed directly,
|
|
rather than via the recommended ``AdminSite.urls`` property, or
|
|
``AdminSite.get_urls()`` method.
|
|
|
|
* Unsupported operations on a sliced queryset now raise ``TypeError`` instead
|
|
of ``AssertionError``.
|
|
|
|
* The undocumented ``django.test.runner.reorder_suite()`` function is renamed
|
|
to ``reorder_tests()``. It now accepts an iterable of tests rather than a
|
|
test suite, and returns an iterator of tests.
|
|
|
|
* Calling ``FileSystemStorage.delete()`` with an empty ``name`` now raises
|
|
``ValueError`` instead of ``AssertionError``.
|
|
|
|
* Calling ``EmailMultiAlternatives.attach_alternative()`` or
|
|
``EmailMessage.attach()`` with an invalid ``content`` or ``mimetype``
|
|
arguments now raise ``ValueError`` instead of ``AssertionError``.
|
|
|
|
* :meth:`~django.test.SimpleTestCase.assertHTMLEqual` no longer considers a
|
|
non-boolean attribute without a value equal to an attribute with the same
|
|
name and value.
|
|
|
|
* Tests that fail to load, for example due to syntax errors, now always match
|
|
when using :option:`test --tag`.
|
|
|
|
* The undocumented ``django.contrib.admin.utils.lookup_needs_distinct()``
|
|
function is renamed to ``lookup_spawns_duplicates()``.
|
|
|
|
* The undocumented ``HttpRequest.get_raw_uri()`` method is removed. The
|
|
:meth:`.HttpRequest.build_absolute_uri` method may be a suitable alternative.
|
|
|
|
* The ``object`` argument of undocumented ``ModelAdmin.log_addition()``,
|
|
``log_change()``, and ``log_deletion()`` methods is renamed to ``obj``.
|
|
|
|
* :class:`~django.utils.feedgenerator.RssFeed`,
|
|
:class:`~django.utils.feedgenerator.Atom1Feed`, and their subclasses now
|
|
emit elements with no content as self-closing tags.
|
|
|
|
.. _deprecated-features-4.0:
|
|
|
|
Features deprecated in 4.0
|
|
==========================
|
|
|
|
Time zone support
|
|
-----------------
|
|
|
|
In order to follow good practice, the default value of the :setting:`USE_TZ`
|
|
setting will change from ``False`` to ``True``, and time zone support will be
|
|
enabled by default, in Django 5.0.
|
|
|
|
Note that the default :file:`settings.py` file created by
|
|
:djadmin:`django-admin startproject <startproject>` includes
|
|
:setting:`USE_TZ = True <USE_TZ>` since Django 1.4.
|
|
|
|
You can set ``USE_TZ`` to ``False`` in your project settings before then to
|
|
opt-out.
|
|
|
|
Miscellaneous
|
|
-------------
|
|
|
|
* ``SERIALIZE`` test setting is deprecated as it can be inferred from the
|
|
:attr:`~django.test.TestCase.databases` with the
|
|
:ref:`serialized_rollback <test-case-serialized-rollback>` option enabled.
|
|
|
|
* The undocumented ``django.utils.baseconv`` module is deprecated.
|
|
|
|
* The undocumented ``django.utils.datetime_safe`` module is deprecated.
|
|
|
|
* The default sitemap protocol for sitemaps built outside the context of a
|
|
request will change from ``'http'`` to ``'https'`` in Django 5.0.
|
|
|
|
Features removed in 4.0
|
|
=======================
|
|
|
|
These features have reached the end of their deprecation cycle and are removed
|
|
in Django 4.0.
|
|
|
|
See :ref:`deprecated-features-3.0` for details on these changes, including how
|
|
to remove usage of these features.
|
|
|
|
* ``django.utils.http.urlquote()``, ``urlquote_plus()``, ``urlunquote()``, and
|
|
``urlunquote_plus()`` are removed.
|
|
|
|
* ``django.utils.encoding.force_text()`` and ``smart_text()`` are removed.
|
|
|
|
* ``django.utils.translation.ugettext()``, ``ugettext_lazy()``,
|
|
``ugettext_noop()``, ``ungettext()``, and ``ungettext_lazy()`` are removed.
|
|
|
|
* ``django.views.i18n.set_language()`` doesn't set the user language in
|
|
``request.session`` (key ``_language``).
|
|
|
|
* ``alias=None`` is required in the signature of
|
|
``django.db.models.Expression.get_group_by_cols()`` subclasses.
|
|
|
|
* ``django.utils.text.unescape_entities()`` is removed.
|
|
|
|
* ``django.utils.http.is_safe_url()`` is removed.
|
|
|
|
See :ref:`deprecated-features-3.1` for details on these changes, including how
|
|
to remove usage of these features.
|
|
|
|
* The ``PASSWORD_RESET_TIMEOUT_DAYS`` setting is removed.
|
|
|
|
* The :lookup:`isnull` lookup no longer allows using non-boolean values as the
|
|
right-hand side.
|
|
|
|
* The ``django.db.models.query_utils.InvalidQuery`` exception class is removed.
|
|
|
|
* The ``django-admin.py`` entry point is removed.
|
|
|
|
* The ``HttpRequest.is_ajax()`` method is removed.
|
|
|
|
* Support for the pre-Django 3.1 encoding format of cookies values used by
|
|
``django.contrib.messages.storage.cookie.CookieStorage`` is removed.
|
|
|
|
* Support for the pre-Django 3.1 password reset tokens in the admin site (that
|
|
use the SHA-1 hashing algorithm) is removed.
|
|
|
|
* Support for the pre-Django 3.1 encoding format of sessions is removed.
|
|
|
|
* Support for the pre-Django 3.1 ``django.core.signing.Signer`` signatures
|
|
(encoded with the SHA-1 algorithm) is removed.
|
|
|
|
* Support for the pre-Django 3.1 ``django.core.signing.dumps()`` signatures
|
|
(encoded with the SHA-1 algorithm) in ``django.core.signing.loads()`` is
|
|
removed.
|
|
|
|
* Support for the pre-Django 3.1 user sessions (that use the SHA-1 algorithm)
|
|
is removed.
|
|
|
|
* The ``get_response`` argument for
|
|
``django.utils.deprecation.MiddlewareMixin.__init__()`` is required and
|
|
doesn't accept ``None``.
|
|
|
|
* The ``providing_args`` argument for ``django.dispatch.Signal`` is removed.
|
|
|
|
* The ``length`` argument for ``django.utils.crypto.get_random_string()`` is
|
|
required.
|
|
|
|
* The ``list`` message for ``ModelMultipleChoiceField`` is removed.
|
|
|
|
* Support for passing raw column aliases to ``QuerySet.order_by()`` is removed.
|
|
|
|
* The ``NullBooleanField`` model field is removed, except for support in
|
|
historical migrations.
|
|
|
|
* ``django.conf.urls.url()`` is removed.
|
|
|
|
* The ``django.contrib.postgres.fields.JSONField`` model field is removed,
|
|
except for support in historical migrations.
|
|
|
|
* ``django.contrib.postgres.fields.jsonb.KeyTransform`` and
|
|
``django.contrib.postgres.fields.jsonb.KeyTextTransform`` are removed.
|
|
|
|
* ``django.contrib.postgres.forms.JSONField`` is removed.
|
|
|
|
* The ``{% ifequal %}`` and ``{% ifnotequal %}`` template tags are removed.
|
|
|
|
* The ``DEFAULT_HASHING_ALGORITHM`` transitional setting is removed.
|