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Once the deprecation period ends CheckConstraint.check() can become the documented method that performs system checks for BaseConstraint subclasses.
867 lines
33 KiB
Plaintext
867 lines
33 KiB
Plaintext
========================
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Django 3.1 release notes
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========================
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*August 4, 2020*
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Welcome to Django 3.1!
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These release notes cover the :ref:`new features <whats-new-3.1>`, as well as
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some :ref:`backwards incompatible changes <backwards-incompatible-3.1>` you'll
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want to be aware of when upgrading from Django 3.0 or earlier. We've
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:ref:`dropped some features<removed-features-3.1>` that have reached the end of
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their deprecation cycle, and we've :ref:`begun the deprecation process for
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some features <deprecated-features-3.1>`.
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See the :doc:`/howto/upgrade-version` guide if you're updating an existing
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project.
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Python compatibility
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====================
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Django 3.1 supports Python 3.6, 3.7, 3.8, and 3.9 (as of 3.1.3). We **highly
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recommend** and only officially support the latest release of each series.
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.. _whats-new-3.1:
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What's new in Django 3.1
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========================
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Asynchronous views and middleware support
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-----------------------------------------
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Django now supports a fully asynchronous request path, including:
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* :ref:`Asynchronous views <async-views>`
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* :ref:`Asynchronous middleware <async-middleware>`
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* :ref:`Asynchronous tests and test client <async-tests>`
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To get started with async views, you need to declare a view using
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``async def``::
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async def my_view(request):
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await asyncio.sleep(0.5)
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return HttpResponse("Hello, async world!")
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All asynchronous features are supported whether you are running under WSGI or
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ASGI mode. However, there will be performance penalties using async code in
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WSGI mode. You can read more about the specifics in :doc:`/topics/async`
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documentation.
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You are free to mix async and sync views, middleware, and tests as much as you
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want. Django will ensure that you always end up with the right execution
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context. We expect most projects will keep the majority of their views
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synchronous, and only have a select few running in async mode - but it is
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entirely your choice.
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Django's ORM, cache layer, and other pieces of code that do long-running
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network calls do not yet support async access. We expect to add support for
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them in upcoming releases. Async views are ideal, however, if you are doing a
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lot of API or HTTP calls inside your view, you can now natively do all those
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HTTP calls in parallel to considerably speed up your view's execution.
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Asynchronous support should be entirely backwards-compatible and we have tried
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to ensure that it has no speed regressions for your existing, synchronous code.
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It should have no noticeable effect on any existing Django projects.
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JSONField for all supported database backends
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---------------------------------------------
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Django now includes :class:`.models.JSONField` and
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:class:`forms.JSONField <django.forms.JSONField>` that can be used on all
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supported database backends. Both fields support the use of custom JSON
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encoders and decoders. The model field supports the introspection,
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:ref:`lookups, and transforms <querying-jsonfield>` that were previously
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PostgreSQL-only::
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from django.db import models
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class ContactInfo(models.Model):
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data = models.JSONField()
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ContactInfo.objects.create(
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data={
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"name": "John",
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"cities": ["London", "Cambridge"],
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"pets": {"dogs": ["Rufus", "Meg"]},
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}
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)
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ContactInfo.objects.filter(
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data__name="John",
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data__pets__has_key="dogs",
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data__cities__contains="London",
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).delete()
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If your project uses ``django.contrib.postgres.fields.JSONField``, plus the
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related form field and transforms, you should adjust to use the new fields,
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and generate and apply a database migration. For now, the old fields and
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transforms are left as a reference to the new ones and are :ref:`deprecated as
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of this release <deprecated-jsonfield>`.
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.. _default-hashing-algorithm-usage:
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``DEFAULT_HASHING_ALGORITHM`` settings
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--------------------------------------
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The new ``DEFAULT_HASHING_ALGORITHM`` transitional setting allows specifying
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the default hashing algorithm to use for encoding cookies, password reset
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tokens in the admin site, user sessions, and signatures created by
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:class:`django.core.signing.Signer` and :meth:`django.core.signing.dumps`.
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Support for SHA-256 was added in Django 3.1. If you are upgrading multiple
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instances of the same project to Django 3.1, you should set
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``DEFAULT_HASHING_ALGORITHM`` to ``'sha1'`` during the transition, in order to
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allow compatibility with the older versions of Django. Note that this requires
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Django 3.1.1+. Once the transition to 3.1 is complete you can stop overriding
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``DEFAULT_HASHING_ALGORITHM``.
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This setting is deprecated as of this release, because support for tokens,
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cookies, sessions, and signatures that use SHA-1 algorithm will be removed in
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Django 4.0.
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Minor features
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--------------
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:mod:`django.contrib.admin`
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~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* The new ``django.contrib.admin.EmptyFieldListFilter`` for
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:attr:`.ModelAdmin.list_filter` allows filtering on empty values (empty
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strings and nulls) in the admin changelist view.
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* Filters in the right sidebar of the admin changelist view now contain a link
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to clear all filters.
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* The admin now has a sidebar on larger screens for easier navigation. It is
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enabled by default but can be disabled by using a custom ``AdminSite`` and
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setting :attr:`.AdminSite.enable_nav_sidebar` to ``False``.
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Rendering the sidebar requires access to the current request in order to set
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CSS and ARIA role affordances. This requires using
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``'django.template.context_processors.request'`` in the
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``'context_processors'`` option of :setting:`OPTIONS <TEMPLATES-OPTIONS>`.
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* Initially empty ``extra`` inlines can now be removed, in the same way as
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dynamically created ones.
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* ``XRegExp`` is upgraded from version 2.0.0 to 3.2.0.
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* jQuery is upgraded from version 3.4.1 to 3.5.1.
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* Select2 library is upgraded from version 4.0.7 to 4.0.13.
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:mod:`django.contrib.auth`
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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* The default iteration count for the PBKDF2 password hasher is increased from
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180,000 to 216,000.
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* The new :setting:`PASSWORD_RESET_TIMEOUT` setting allows defining the number
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of seconds a password reset link is valid for. This is encouraged instead of
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the deprecated ``PASSWORD_RESET_TIMEOUT_DAYS`` setting, which will be removed
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in Django 4.0.
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* The password reset mechanism now uses the SHA-256 hashing algorithm. Support
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for tokens that use the old hashing algorithm remains until Django 4.0.
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* :meth:`.AbstractBaseUser.get_session_auth_hash` now uses the SHA-256 hashing
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algorithm. Support for user sessions that use the old hashing algorithm
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remains until Django 4.0.
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:mod:`django.contrib.contenttypes`
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* The new :option:`remove_stale_contenttypes --include-stale-apps` option
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allows removing stale content types from previously installed apps that have
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been removed from :setting:`INSTALLED_APPS`.
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:mod:`django.contrib.gis`
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~~~~~~~~~~~~~~~~~~~~~~~~~
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* :lookup:`relate` lookup is now supported on MariaDB.
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* Added the :attr:`.LinearRing.is_counterclockwise` property.
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* :class:`~django.contrib.gis.db.models.functions.AsGeoJSON` is now supported
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on Oracle.
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* Added the :class:`~django.contrib.gis.db.models.functions.AsWKB` and
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:class:`~django.contrib.gis.db.models.functions.AsWKT` functions.
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* Added support for PostGIS 3 and GDAL 3.
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:mod:`django.contrib.humanize`
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* :tfilter:`intword` template filter now supports negative integers.
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:mod:`django.contrib.postgres`
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* The new :class:`~django.contrib.postgres.indexes.BloomIndex` class allows
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creating ``bloom`` indexes in the database. The new
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:class:`~django.contrib.postgres.operations.BloomExtension` migration
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operation installs the ``bloom`` extension to add support for this index.
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* :meth:`~django.db.models.Model.get_FOO_display` now supports
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:class:`~django.contrib.postgres.fields.ArrayField` and
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:class:`~django.contrib.postgres.fields.RangeField`.
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* The new :lookup:`rangefield.lower_inc`, :lookup:`rangefield.lower_inf`,
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:lookup:`rangefield.upper_inc`, and :lookup:`rangefield.upper_inf` lookups
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allow querying :class:`~django.contrib.postgres.fields.RangeField` by a bound
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type.
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* :lookup:`rangefield.contained_by` now supports
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:class:`~django.db.models.SmallAutoField`,
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:class:`~django.db.models.AutoField`,
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:class:`~django.db.models.BigAutoField`,
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:class:`~django.db.models.SmallIntegerField`, and
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:class:`~django.db.models.DecimalField`.
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* :class:`~django.contrib.postgres.search.SearchQuery` now supports
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``'websearch'`` search type on PostgreSQL 11+.
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* :class:`SearchQuery.value <django.contrib.postgres.search.SearchQuery>` now
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supports query expressions.
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* The new :class:`~django.contrib.postgres.search.SearchHeadline` class allows
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highlighting search results.
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* :lookup:`search` lookup now supports query expressions.
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* The new ``cover_density`` parameter of
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:class:`~django.contrib.postgres.search.SearchRank` allows ranking by cover
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density.
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* The new ``normalization`` parameter of
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:class:`~django.contrib.postgres.search.SearchRank` allows rank
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normalization.
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* The new :attr:`.ExclusionConstraint.deferrable` attribute allows creating
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deferrable exclusion constraints.
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:mod:`django.contrib.sessions`
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* The :setting:`SESSION_COOKIE_SAMESITE` setting now allows ``'None'`` (string)
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value to explicitly state that the cookie is sent with all same-site and
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cross-site requests.
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:mod:`django.contrib.staticfiles`
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* The :setting:`STATICFILES_DIRS` setting now supports :class:`pathlib.Path`.
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Cache
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~~~~~
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* The :func:`~django.views.decorators.cache.cache_control` decorator and
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:func:`~django.utils.cache.patch_cache_control` method now support multiple
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field names in the ``no-cache`` directive for the ``Cache-Control`` header,
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according to :rfc:`7234#section-5.2.2.2`.
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* :meth:`~django.core.cache.cache.delete` now returns ``True`` if the key was
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successfully deleted, ``False`` otherwise.
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CSRF
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~~~~
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* The :setting:`CSRF_COOKIE_SAMESITE` setting now allows ``'None'`` (string)
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value to explicitly state that the cookie is sent with all same-site and
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cross-site requests.
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Email
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~~~~~
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* The :setting:`EMAIL_FILE_PATH` setting, used by the :ref:`file email backend
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<topic-email-file-backend>`, now supports :class:`pathlib.Path`.
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Error Reporting
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~~~~~~~~~~~~~~~
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* :class:`django.views.debug.SafeExceptionReporterFilter` now filters sensitive
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values from ``request.META`` in exception reports.
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* The new :attr:`.SafeExceptionReporterFilter.cleansed_substitute` and
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:attr:`.SafeExceptionReporterFilter.hidden_settings` attributes allow
|
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customization of sensitive settings and ``request.META`` filtering in
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exception reports.
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* The technical 404 debug view now respects
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:setting:`DEFAULT_EXCEPTION_REPORTER_FILTER` when applying settings
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filtering.
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* The new :setting:`DEFAULT_EXCEPTION_REPORTER` allows providing a
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:class:`django.views.debug.ExceptionReporter` subclass to customize exception
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report generation. See :ref:`custom-error-reports` for details.
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File Storage
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~~~~~~~~~~~~
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* ``FileSystemStorage.save()`` method now supports :class:`pathlib.Path`.
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* :class:`~django.db.models.FileField` and
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:class:`~django.db.models.ImageField` now accept a callable for ``storage``.
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This allows you to modify the used storage at runtime, selecting different
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storages for different environments, for example.
|
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Forms
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~~~~~
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* :class:`~django.forms.ModelChoiceIterator`, used by
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:class:`~django.forms.ModelChoiceField` and
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:class:`~django.forms.ModelMultipleChoiceField`, now uses
|
|
:class:`~django.forms.ModelChoiceIteratorValue` that can be used by widgets
|
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to access model instances. See :ref:`iterating-relationship-choices` for
|
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details.
|
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* :class:`django.forms.DateTimeField` now accepts dates in a subset of ISO 8601
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datetime formats, including optional timezone, e.g. ``2019-10-10T06:47``,
|
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``2019-10-10T06:47:23+04:00``, or ``2019-10-10T06:47:23Z``. The timezone will
|
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always be retained if provided, with timezone-aware datetimes being returned
|
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even when :setting:`USE_TZ` is ``False``.
|
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Additionally, ``DateTimeField`` now uses ``DATE_INPUT_FORMATS`` in addition
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to ``DATETIME_INPUT_FORMATS`` when converting a field input to a ``datetime``
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value.
|
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* :attr:`.MultiWidget.widgets` now accepts a dictionary which allows
|
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customizing subwidget ``name`` attributes.
|
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|
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* The new :attr:`.BoundField.widget_type` property can be used to dynamically
|
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adjust form rendering based upon the widget type.
|
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|
Internationalization
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~~~~~~~~~~~~~~~~~~~~
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* The :setting:`LANGUAGE_COOKIE_SAMESITE` setting now allows ``'None'``
|
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(string) value to explicitly state that the cookie is sent with all same-site
|
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and cross-site requests.
|
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* Added support and translations for the Algerian Arabic, Igbo, Kyrgyz, Tajik,
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and Turkmen languages.
|
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|
Management Commands
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|
~~~~~~~~~~~~~~~~~~~
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* The new :option:`check --database` option allows specifying database aliases
|
|
for running the ``database`` system checks. Previously these checks were
|
|
enabled for all configured :setting:`DATABASES` by passing the ``database``
|
|
tag to the command.
|
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|
|
* The new :option:`migrate --check` option makes the command exit with a
|
|
non-zero status when unapplied migrations are detected.
|
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|
* The new ``returncode`` argument for
|
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:attr:`~django.core.management.CommandError` allows customizing the exit
|
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status for management commands.
|
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* The new :option:`dbshell -- ARGUMENTS <dbshell -->` option allows passing
|
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extra arguments to the command-line client for the database.
|
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|
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* The :djadmin:`flush` and :djadmin:`sqlflush` commands now include SQL to
|
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reset sequences on SQLite.
|
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|
|
Models
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~~~~~~
|
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|
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* The new :class:`~django.db.models.functions.ExtractIsoWeekDay` function
|
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extracts ISO-8601 week days from :class:`~django.db.models.DateField` and
|
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: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:
|
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|
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* ``TREE`` format on MySQL 8.0.16+,
|
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* ``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
|
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``OneToOneField`` emulates the behavior of the SQL constraint ``ON DELETE
|
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RESTRICT``.
|
|
|
|
* ``CheckConstraint.check`` now supports boolean expressions.
|
|
|
|
* The :meth:`.RelatedManager.add`, :meth:`~.RelatedManager.create`, and
|
|
:meth:`~.RelatedManager.set` methods now accept callables as values in the
|
|
``through_defaults`` argument.
|
|
|
|
* The new ``is_dst`` parameter of the :meth:`.QuerySet.datetimes` determines
|
|
the treatment of nonexistent and ambiguous datetimes.
|
|
|
|
* The new :class:`~django.db.models.F` expression ``bitxor()`` method allows
|
|
:ref:`bitwise XOR operation <using-f-expressions-in-filters>`.
|
|
|
|
* :meth:`.QuerySet.bulk_create` now sets the primary key on objects when using
|
|
MariaDB 10.5+.
|
|
|
|
* The ``DatabaseOperations.sql_flush()`` method now generates more efficient
|
|
SQL on MySQL by using ``DELETE`` instead of ``TRUNCATE`` statements for
|
|
tables which don't require resetting sequences.
|
|
|
|
* SQLite functions are now marked as :py:meth:`deterministic
|
|
<sqlite3.Connection.create_function>` on Python 3.8+. This allows using them
|
|
in check constraints and partial indexes.
|
|
|
|
* The new :attr:`.UniqueConstraint.deferrable` attribute allows creating
|
|
deferrable unique constraints.
|
|
|
|
Pagination
|
|
~~~~~~~~~~
|
|
|
|
* :class:`~django.core.paginator.Paginator` can now be iterated over to yield
|
|
its pages.
|
|
|
|
Requests and Responses
|
|
~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* If :setting:`ALLOWED_HOSTS` is empty and ``DEBUG=True``, subdomains of
|
|
localhost are now allowed in the ``Host`` header, e.g. ``static.localhost``.
|
|
|
|
* :meth:`.HttpResponse.set_cookie` and :meth:`.HttpResponse.set_signed_cookie`
|
|
now allow using ``samesite='None'`` (string) to explicitly state that the
|
|
cookie is sent with all same-site and cross-site requests.
|
|
|
|
* The new :meth:`.HttpRequest.accepts` method returns whether the request
|
|
accepts the given MIME type according to the ``Accept`` HTTP header.
|
|
|
|
.. _whats-new-security-3.1:
|
|
|
|
Security
|
|
~~~~~~~~
|
|
|
|
* The :setting:`SECURE_REFERRER_POLICY` setting now defaults to
|
|
``'same-origin'``. With this configured,
|
|
:class:`~django.middleware.security.SecurityMiddleware` sets the
|
|
:ref:`referrer-policy` header to ``same-origin`` on all responses that do not
|
|
already have it. This prevents the ``Referer`` header being sent to other
|
|
origins. If you need the previous behavior, explicitly set
|
|
:setting:`SECURE_REFERRER_POLICY` to ``None``.
|
|
|
|
* The default algorithm of :class:`django.core.signing.Signer`,
|
|
:meth:`django.core.signing.loads`, and :meth:`django.core.signing.dumps` is
|
|
changed to the SHA-256. Support for signatures made with the old SHA-1
|
|
algorithm remains until Django 4.0.
|
|
|
|
Also, the new ``algorithm`` parameter of the
|
|
:class:`~django.core.signing.Signer` allows customizing the hashing
|
|
algorithm.
|
|
|
|
Templates
|
|
~~~~~~~~~
|
|
|
|
* The renamed :ttag:`translate` and :ttag:`blocktranslate` template tags are
|
|
introduced for internationalization in template code. The older :ttag:`trans`
|
|
and :ttag:`blocktrans` template tags aliases continue to work, and will be
|
|
retained for the foreseeable future.
|
|
|
|
* The :ttag:`include` template tag now accepts iterables of template names.
|
|
|
|
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_MIGRATE>` test database setting allows
|
|
disabling of migrations during a test database creation.
|
|
|
|
* :class:`~django.test.runner.DiscoverRunner` can now discard output for
|
|
passing tests using the :option:`test --buffer` option.
|
|
|
|
* :class:`~django.test.runner.DiscoverRunner` now skips running the system
|
|
checks on databases not :ref:`referenced by tests<testing-multi-db>`.
|
|
|
|
* :class:`~django.test.TransactionTestCase` teardown is now faster on MySQL
|
|
due to :djadmin:`flush` command improvements. As a side effect the latter
|
|
doesn't automatically reset sequences on teardown anymore. Enable
|
|
:attr:`.TransactionTestCase.reset_sequences` if your tests require this
|
|
feature.
|
|
|
|
URLs
|
|
~~~~
|
|
|
|
* :ref:`Path converters <registering-custom-path-converters>` can now raise
|
|
``ValueError`` in ``to_url()`` to indicate no match when reversing 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.
|
|
|
|
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.
|
|
|
|
* The :setting:`TIME_ZONE <DATABASE-TIME_ZONE>` setting is now allowed on
|
|
databases that support time zones.
|
|
|
|
.. _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.
|
|
|
|
* ``connection.timezone`` property is now ``'UTC'`` by default, or the
|
|
:setting:`TIME_ZONE <DATABASE-TIME_ZONE>` when :setting:`USE_TZ` is ``True``
|
|
on databases that support time zones. Previously, it was ``None`` on
|
|
databases that support time zones.
|
|
|
|
* ``connection._nodb_connection`` property is changed to the
|
|
``connection._nodb_cursor()`` method and now returns a context manager that
|
|
yields a cursor and automatically closes the cursor and connection upon
|
|
exiting the ``with`` statement.
|
|
|
|
* ``DatabaseClient.runshell()`` now requires an additional ``parameters``
|
|
argument as a list of extra arguments to pass on to the command-line client.
|
|
|
|
* The ``sequences`` positional argument of ``DatabaseOperations.sql_flush()``
|
|
is replaced by the boolean keyword-only argument ``reset_sequences``. If
|
|
``True``, the sequences of the truncated tables will be reset.
|
|
|
|
* The ``allow_cascade`` argument of ``DatabaseOperations.sql_flush()`` is now a
|
|
keyword-only argument.
|
|
|
|
* The ``using`` positional argument of
|
|
``DatabaseOperations.execute_sql_flush()`` is removed. The method now uses
|
|
the database of the called instance.
|
|
|
|
* Third-party database backends must implement support for ``JSONField`` or set
|
|
``DatabaseFeatures.supports_json_field`` to ``False``. If storing primitives
|
|
is not supported, set ``DatabaseFeatures.supports_primitives_in_json_field``
|
|
to ``False``. If there is a true datatype for JSON, set
|
|
``DatabaseFeatures.has_native_json_field`` to ``True``. If
|
|
:lookup:`jsonfield.contains` and :lookup:`jsonfield.contained_by` are not
|
|
supported, set ``DatabaseFeatures.supports_json_field_contains`` to
|
|
``False``.
|
|
|
|
* Third party database backends must implement introspection for ``JSONField``
|
|
or set ``can_introspect_json_field`` to ``False``.
|
|
|
|
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.
|
|
|
|
``contrib.admin`` browser support
|
|
---------------------------------
|
|
|
|
The admin no longer supports the legacy Internet Explorer browser. See
|
|
:ref:`the admin FAQ <admin-browser-support>` for details on supported browsers.
|
|
|
|
:attr:`AbstractUser.first_name <django.contrib.auth.models.User.first_name>` ``max_length`` increased to 150
|
|
------------------------------------------------------------------------------------------------------------
|
|
|
|
A migration for :attr:`django.contrib.auth.models.User.first_name` is included.
|
|
If you have a custom user model inheriting from ``AbstractUser``, you'll need
|
|
to generate and apply a database migration for your user model.
|
|
|
|
If you want to preserve the 30 character limit for first names, use a custom
|
|
form::
|
|
|
|
from django import forms
|
|
from django.contrib.auth.forms import UserChangeForm
|
|
|
|
|
|
class MyUserChangeForm(UserChangeForm):
|
|
first_name = forms.CharField(max_length=30, required=False)
|
|
|
|
If you wish to keep this restriction in the admin when editing users, set
|
|
``UserAdmin.form`` to use this form::
|
|
|
|
from django.contrib.auth.admin import UserAdmin
|
|
from django.contrib.auth.models import User
|
|
|
|
|
|
class MyUserAdmin(UserAdmin):
|
|
form = MyUserChangeForm
|
|
|
|
|
|
admin.site.unregister(User)
|
|
admin.site.register(User, MyUserAdmin)
|
|
|
|
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 logic behind the decision to return a redirection fallback or a 204 HTTP
|
|
response from the :func:`~django.views.i18n.set_language` view is now based
|
|
on the ``Accept`` HTTP header instead of the ``X-Requested-With`` HTTP header
|
|
presence.
|
|
|
|
* 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 made public and
|
|
moved to :class:`django.utils.functional.classproperty()`.
|
|
|
|
* :tfilter:`floatformat` template filter now outputs (positive) ``0`` for
|
|
negative numbers which round to zero.
|
|
|
|
* :attr:`Meta.ordering <django.db.models.Options.ordering>` and
|
|
:attr:`Meta.unique_together <django.db.models.Options.unique_together>`
|
|
options on models in ``django.contrib`` modules that were formerly tuples are
|
|
now lists.
|
|
|
|
* The admin calendar widget now handles two-digit years according to the Open
|
|
Group Specification, i.e. values between 69 and 99 are mapped to the previous
|
|
century, and values between 0 and 68 are mapped to the current century.
|
|
|
|
* Date-only formats are removed from the default list for
|
|
:setting:`DATETIME_INPUT_FORMATS`.
|
|
|
|
* The :class:`~django.forms.FileInput` widget no longer renders with the
|
|
``required`` HTML attribute when initial data exists.
|
|
|
|
* The undocumented ``django.views.debug.ExceptionReporterFilter`` class is
|
|
removed. As per the :ref:`custom-error-reports` documentation, classes to be
|
|
used with :setting:`DEFAULT_EXCEPTION_REPORTER_FILTER` need to inherit from
|
|
:class:`django.views.debug.SafeExceptionReporterFilter`.
|
|
|
|
* The cache timeout set by :func:`~django.views.decorators.cache.cache_page`
|
|
decorator now takes precedence over the ``max-age`` directive from the
|
|
``Cache-Control`` header.
|
|
|
|
* Providing a non-local remote field in the :attr:`.ForeignKey.to_field`
|
|
argument now raises :class:`~django.core.exceptions.FieldError`.
|
|
|
|
* :setting:`SECURE_REFERRER_POLICY` now defaults to ``'same-origin'``. See the
|
|
*What's New* :ref:`Security section <whats-new-security-3.1>` above for more
|
|
details.
|
|
|
|
* :djadmin:`check` management command now runs the ``database`` system checks
|
|
only for database aliases specified using :option:`check --database` option.
|
|
|
|
* :djadmin:`migrate` management command now runs the ``database`` system checks
|
|
only for a database to migrate.
|
|
|
|
* The admin CSS classes ``row1`` and ``row2`` are removed in favor of
|
|
``:nth-child(odd)`` and ``:nth-child(even)`` pseudo-classes.
|
|
|
|
* The :func:`~django.contrib.auth.hashers.make_password` function now requires
|
|
its argument to be a string or bytes. Other types should be explicitly cast
|
|
to one of these.
|
|
|
|
* The undocumented ``version`` parameter to the
|
|
:class:`~django.contrib.gis.db.models.functions.AsKML` function is removed.
|
|
|
|
* :ref:`JSON and YAML serializers <serialization-formats>`, used by
|
|
:djadmin:`dumpdata`, now dump all data with Unicode by default. If you need
|
|
the previous behavior, pass ``ensure_ascii=True`` to JSON serializer, or
|
|
``allow_unicode=False`` to YAML serializer.
|
|
|
|
* The auto-reloader no longer monitors changes in built-in Django translation
|
|
files.
|
|
|
|
* The minimum supported version of ``mysqlclient`` is increased from 1.3.13 to
|
|
1.4.0.
|
|
|
|
* The undocumented ``django.contrib.postgres.forms.InvalidJSONInput`` and
|
|
``django.contrib.postgres.forms.JSONString`` are moved to
|
|
``django.forms.fields``.
|
|
|
|
* The undocumented ``django.contrib.postgres.fields.jsonb.JsonAdapter`` class
|
|
is removed.
|
|
|
|
* The :ttag:`{% localize off %} <localize>` tag and :tfilter:`unlocalize`
|
|
filter no longer respect :setting:`DECIMAL_SEPARATOR` setting.
|
|
|
|
* The minimum supported version of ``asgiref`` is increased from 3.2 to
|
|
3.2.10.
|
|
|
|
* The :doc:`Media </topics/forms/media>` class now renders ``<script>`` tags
|
|
without the ``type`` attribute to follow `WHATWG recommendations
|
|
<https://html.spec.whatwg.org/multipage/scripting.html#the-script-element>`_.
|
|
|
|
* :class:`~django.forms.ModelChoiceIterator`, used by
|
|
:class:`~django.forms.ModelChoiceField` and
|
|
:class:`~django.forms.ModelMultipleChoiceField`, now yields 2-tuple choices
|
|
containing :class:`~django.forms.ModelChoiceIteratorValue` instances as the
|
|
first ``value`` element in each choice. In most cases this proxies
|
|
transparently, but if you need the ``field`` value itself, use the
|
|
:attr:`.ModelChoiceIteratorValue.value` attribute instead.
|
|
|
|
.. _deprecated-features-3.1:
|
|
|
|
Features deprecated in 3.1
|
|
==========================
|
|
|
|
.. _deprecated-jsonfield:
|
|
|
|
PostgreSQL ``JSONField``
|
|
------------------------
|
|
|
|
``django.contrib.postgres.fields.JSONField`` and
|
|
``django.contrib.postgres.forms.JSONField`` are deprecated in favor of
|
|
:class:`.models.JSONField` and
|
|
:class:`forms.JSONField <django.forms.JSONField>`.
|
|
|
|
The undocumented ``django.contrib.postgres.fields.jsonb.KeyTransform`` and
|
|
``django.contrib.postgres.fields.jsonb.KeyTextTransform`` are also deprecated
|
|
in favor of the transforms in ``django.db.models.fields.json``.
|
|
|
|
The new ``JSONField``\s, ``KeyTransform``, and ``KeyTextTransform`` can be used
|
|
on all supported database backends.
|
|
|
|
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`.
|
|
|
|
* The ``django-admin.py`` entry point is deprecated in favor of
|
|
``django-admin``.
|
|
|
|
* The ``HttpRequest.is_ajax()`` method is deprecated as it relied on a
|
|
jQuery-specific way of signifying AJAX calls, while current usage tends to
|
|
use the JavaScript `Fetch API
|
|
<https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API>`_. Depending on
|
|
your use case, you can either write your own AJAX detection method, or use
|
|
the new :meth:`.HttpRequest.accepts` method if your code depends on the
|
|
client ``Accept`` HTTP header.
|
|
|
|
If you are writing your own AJAX detection method, ``request.is_ajax()`` can
|
|
be reproduced exactly as
|
|
``request.headers.get('x-requested-with') == 'XMLHttpRequest'``.
|
|
|
|
* Passing ``None`` as the first argument to
|
|
``django.utils.deprecation.MiddlewareMixin.__init__()`` is deprecated.
|
|
|
|
* The encoding format of cookies values used by
|
|
:class:`~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 4.0.
|
|
|
|
* The encoding format of sessions is different from the format generated by
|
|
older versions of Django. Support for the old format remains until Django
|
|
4.0.
|
|
|
|
* The purely documentational ``providing_args`` argument for
|
|
:class:`~django.dispatch.Signal` is deprecated. If you rely on this
|
|
argument as documentation, you can move the text to a code comment or
|
|
docstring.
|
|
|
|
* Calling ``django.utils.crypto.get_random_string()`` without a ``length``
|
|
argument is deprecated.
|
|
|
|
* The ``list`` message for :class:`~django.forms.ModelMultipleChoiceField` is
|
|
deprecated in favor of ``invalid_list``.
|
|
|
|
* Passing raw column aliases to :meth:`.QuerySet.order_by` is deprecated. The
|
|
same result can be achieved by passing aliases in a
|
|
:class:`~django.db.models.expressions.RawSQL` instead beforehand.
|
|
|
|
* The ``NullBooleanField`` model field is deprecated in favor of
|
|
``BooleanField(null=True, blank=True)``.
|
|
|
|
* ``django.conf.urls.url()`` alias of :func:`django.urls.re_path` is
|
|
deprecated.
|
|
|
|
* The ``{% ifequal %}`` and ``{% ifnotequal %}`` template tags are deprecated
|
|
in favor of :ttag:`{% if %}<if>`. ``{% if %}`` covers all use cases, but if
|
|
you need to continue using these tags, they can be extracted from Django to a
|
|
module and included as a built-in tag in the :class:`'builtins'
|
|
<django.template.backends.django.DjangoTemplates>` option in
|
|
:setting:`OPTIONS <TEMPLATES-OPTIONS>`.
|
|
|
|
* ``DEFAULT_HASHING_ALGORITHM`` transitional setting is deprecated.
|
|
|
|
.. _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.
|