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			Plaintext
		
	
	
	
	
	
| ========================
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| Django 2.0 release notes
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| ========================
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| 
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| *December 2, 2017*
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| 
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| Welcome to Django 2.0!
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| 
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| These release notes cover the :ref:`new features <whats-new-2.0>`, as well as
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| some :ref:`backwards incompatible changes <backwards-incompatible-2.0>` you'll
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| want to be aware of when upgrading from Django 1.11 or earlier. We've
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| :ref:`dropped some features<removed-features-2.0>` that have reached the end of
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| their deprecation cycle, and we've :ref:`begun the deprecation process for some
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| features <deprecated-features-2.0>`.
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| 
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| This release starts Django's use of a :ref:`loose form of semantic versioning
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| <internal-release-cadence>`, but there aren't any major backwards incompatible
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| changes that might be expected of a 2.0 release. Upgrading should be a similar
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| amount of effort as past feature releases.
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| 
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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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| 
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| Python compatibility
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| ====================
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| 
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| Django 2.0 supports Python 3.4, 3.5, 3.6, and 3.7. We **highly recommend** and
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| only officially support the latest release of each series.
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| 
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| The Django 1.11.x series is the last to support Python 2.7.
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| 
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| Django 2.0 will be the last release series to support Python 3.4. If you plan
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| a deployment of Python 3.4 beyond the end-of-life for Django 2.0 (April 2019),
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| stick with Django 1.11 LTS (supported until April 2020) instead. Note, however,
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| that the end-of-life for Python 3.4 is March 2019.
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| 
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| Third-party library support for older version of Django
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| =======================================================
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| 
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| Following the release of Django 2.0, we suggest that third-party app authors
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| drop support for all versions of Django prior to 1.11. At that time, you should
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| be able to run your package's tests using ``python -Wd`` so that deprecation
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| warnings do appear. After making the deprecation warning fixes, your app should
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| be compatible with Django 2.0.
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| 
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| .. _whats-new-2.0:
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| 
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| What's new in Django 2.0
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| ========================
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| 
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| Simplified URL routing syntax
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| -----------------------------
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| 
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| The new :func:`django.urls.path()` function allows a simpler, more readable URL
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| routing syntax. For example, this example from previous Django releases::
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| 
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|     url(r'^articles/(?P<year>[0-9]{4})/$', views.year_archive),
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| 
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| could be written as::
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| 
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|     path('articles/<int:year>/', views.year_archive),
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| 
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| The new syntax supports type coercion of URL parameters. In the example, the
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| view will receive the ``year`` keyword argument as an integer rather than as
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| a string. Also, the URLs that will match are slightly less constrained in the
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| rewritten example. For example, the year 10000 will now match since the year
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| integers aren't constrained to be exactly four digits long as they are in the
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| regular expression.
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| 
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| The ``django.conf.urls.url()`` function from previous versions is now available
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| as :func:`django.urls.re_path`. The old location remains for backwards
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| compatibility, without an imminent deprecation. The old
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| ``django.conf.urls.include()`` function is now importable from ``django.urls``
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| so you can use ``from django.urls import include, path, re_path`` in your
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| URLconfs.
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| 
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| The :doc:`/topics/http/urls` document is rewritten to feature the new syntax
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| and provide more details.
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| 
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| Mobile-friendly ``contrib.admin``
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| ---------------------------------
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| 
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| The admin is now responsive and supports all major mobile devices. Older
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| browsers may experience varying levels of graceful degradation.
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| 
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| Window expressions
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| ------------------
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| 
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| The new :class:`~django.db.models.expressions.Window` expression allows
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| adding an ``OVER`` clause to querysets. You can use :ref:`window functions
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| <window-functions>` and :ref:`aggregate functions <aggregation-functions>` in
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| the expression.
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| 
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| Minor features
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| --------------
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| 
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| :mod:`django.contrib.admin`
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| ~~~~~~~~~~~~~~~~~~~~~~~~~~~
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| 
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| * The new :attr:`.ModelAdmin.autocomplete_fields` attribute and
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|   :meth:`.ModelAdmin.get_autocomplete_fields` method allow using a
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|   `Select2 <https://select2.org>`_ search widget for ``ForeignKey`` and
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|   ``ManyToManyField``.
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| 
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| :mod:`django.contrib.auth`
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| ~~~~~~~~~~~~~~~~~~~~~~~~~~
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| 
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| * The default iteration count for the PBKDF2 password hasher is increased from
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|   36,000 to 100,000.
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| 
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| :mod:`django.contrib.gis`
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| ~~~~~~~~~~~~~~~~~~~~~~~~~
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| 
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| * Added MySQL support for the
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|   :class:`~django.contrib.gis.db.models.functions.AsGeoJSON` function,
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|   :class:`~django.contrib.gis.db.models.functions.GeoHash` function,
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|   :class:`~django.contrib.gis.db.models.functions.IsValid` function,
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|   :lookup:`isvalid` lookup, and :ref:`distance lookups <distance-lookups>`.
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| 
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| * Added the :class:`~django.contrib.gis.db.models.functions.Azimuth` and
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|   :class:`~django.contrib.gis.db.models.functions.LineLocatePoint` functions,
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|   supported on PostGIS and SpatiaLite.
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| 
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| * Any :class:`~django.contrib.gis.geos.GEOSGeometry` imported from GeoJSON now
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|   has its SRID set.
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| 
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| * Added the :attr:`.OSMWidget.default_zoom` attribute to customize the map's
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|   default zoom level.
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| 
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| * Made metadata readable and editable on rasters through the
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|   :attr:`~django.contrib.gis.gdal.GDALRaster.metadata`,
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|   :attr:`~django.contrib.gis.gdal.GDALRaster.info`, and
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|   :attr:`~django.contrib.gis.gdal.GDALBand.metadata` attributes.
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| 
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| * Allowed passing driver-specific creation options to
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|   :class:`~django.contrib.gis.gdal.GDALRaster` objects using ``papsz_options``.
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| 
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| * Allowed creating :class:`~django.contrib.gis.gdal.GDALRaster` objects in
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|   GDAL's internal virtual filesystem. Rasters can now be :ref:`created from and
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|   converted to binary data <gdal-raster-vsimem>` in-memory.
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| 
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| * The new :meth:`GDALBand.color_interp()
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|   <django.contrib.gis.gdal.GDALBand.color_interp>` method returns the color
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|   interpretation for the band.
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| 
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| :mod:`django.contrib.postgres`
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| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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| 
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| * The new ``distinct`` argument for
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|   :class:`~django.contrib.postgres.aggregates.ArrayAgg` determines if
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|   concatenated values will be distinct.
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| 
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| * The new :class:`~django.contrib.postgres.functions.RandomUUID` database
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|   function returns a version 4 UUID. It requires use of PostgreSQL's
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|   ``pgcrypto`` extension which can be activated using the new
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|   :class:`~django.contrib.postgres.operations.CryptoExtension` migration
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|   operation.
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| 
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| * :class:`django.contrib.postgres.indexes.GinIndex` now supports the
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|   ``fastupdate`` and ``gin_pending_list_limit`` parameters.
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| 
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| * The new :class:`~django.contrib.postgres.indexes.GistIndex` class allows
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|   creating ``GiST`` indexes in the database. The new
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|   :class:`~django.contrib.postgres.operations.BtreeGistExtension` migration
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|   operation installs the ``btree_gist`` extension to add support for operator
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|   classes that aren't built-in.
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| 
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| * :djadmin:`inspectdb` can now introspect ``JSONField`` and various
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|   ``RangeField``\s (``django.contrib.postgres`` must be in ``INSTALLED_APPS``).
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| 
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| :mod:`django.contrib.sitemaps`
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| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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| 
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| * Added the ``protocol`` keyword argument to the
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|   :class:`~django.contrib.sitemaps.GenericSitemap` constructor.
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| 
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| Cache
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| ~~~~~
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| 
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| * ``cache.set_many()`` now returns a list of keys that failed to be inserted.
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|   For the built-in backends, failed inserts can only happen on memcached.
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| 
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| File Storage
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| ~~~~~~~~~~~~
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| 
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| * :meth:`File.open() <django.core.files.File.open>` can be used as a context
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|   manager, e.g. ``with file.open() as f:``.
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| 
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| Forms
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| ~~~~~
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| 
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| * The new ``date_attrs`` and ``time_attrs`` arguments for
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|   :class:`~django.forms.SplitDateTimeWidget` and
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|   :class:`~django.forms.SplitHiddenDateTimeWidget` allow specifying different
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|   HTML attributes for the ``DateInput`` and ``TimeInput`` (or hidden)
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|   subwidgets.
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| 
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| * The new :meth:`Form.errors.get_json_data()
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|   <django.forms.Form.errors.get_json_data>` method returns form errors as
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|   a dictionary suitable for including in a JSON response.
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| 
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| Generic Views
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| ~~~~~~~~~~~~~
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| 
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| * The new :attr:`.ContextMixin.extra_context` attribute allows adding context
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|   in ``View.as_view()``.
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| 
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| Management Commands
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| ~~~~~~~~~~~~~~~~~~~
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| 
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| * :djadmin:`inspectdb` now translates MySQL's unsigned integer columns to
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|   ``PositiveIntegerField`` or ``PositiveSmallIntegerField``.
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| 
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| * The new :option:`makemessages --add-location` option controls the comment
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|   format in PO files.
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| 
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| * :djadmin:`loaddata` can now :ref:`read from stdin <loading-fixtures-stdin>`.
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| 
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| * The new :option:`diffsettings --output` option allows formatting the output
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|   in a unified diff format.
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| 
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| * On Oracle, :djadmin:`inspectdb` can now introspect ``AutoField`` if the
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|   column is created as an identity column.
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| 
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| * On MySQL, :djadmin:`dbshell` now supports client-side TLS certificates.
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| 
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| Migrations
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| ~~~~~~~~~~
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| 
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| * The new :option:`squashmigrations --squashed-name` option allows naming the
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|   squashed migration.
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| 
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| Models
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| ~~~~~~
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| 
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| * The new :class:`~django.db.models.functions.StrIndex` database function
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|   finds the starting index of a string inside another string.
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| 
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| * On Oracle, ``AutoField`` and ``BigAutoField`` are now created as `identity
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|   columns <https://docs.oracle.com/en/database/oracle/oracle-database/18/drdaa/
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|   intro-to-tools-and-products-supporting-migraiton.html#GUID-14E4817B-F3BC-4D99
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|   -B471-A0ACDC303CC9>`__.
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| 
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| * The new ``chunk_size`` parameter of :meth:`.QuerySet.iterator` controls the
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|   number of rows fetched by the Python database client when streaming results
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|   from the database. For databases that don't support server-side cursors, it
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|   controls the number of results Django fetches from the database adapter.
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| 
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| * :meth:`.QuerySet.earliest`, :meth:`.QuerySet.latest`, and
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|   :attr:`Meta.get_latest_by <django.db.models.Options.get_latest_by>` now
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|   allow ordering by several fields.
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| 
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| * Added the :class:`~django.db.models.functions.ExtractQuarter` function to
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|   extract the quarter from :class:`~django.db.models.DateField` and
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|   :class:`~django.db.models.DateTimeField`, and exposed it through the
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|   :lookup:`quarter` lookup.
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| 
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| * Added the :class:`~django.db.models.functions.TruncQuarter` function to
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|   truncate :class:`~django.db.models.DateField` and
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|   :class:`~django.db.models.DateTimeField` to the first day of a quarter.
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| 
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| * Added the :attr:`~django.db.models.Index.db_tablespace` parameter to
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|   class-based indexes.
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| 
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| * If the database supports a native duration field (Oracle and PostgreSQL),
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|   :class:`~django.db.models.functions.Extract` now works with
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|   :class:`~django.db.models.DurationField`.
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| 
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| * Added the ``of`` argument to :meth:`.QuerySet.select_for_update()`, supported
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|   on PostgreSQL and Oracle, to lock only rows from specific tables rather than
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|   all selected tables. It may be helpful particularly when
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|   :meth:`~.QuerySet.select_for_update()` is used in conjunction with
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|   :meth:`~.QuerySet.select_related()`.
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| 
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| * The new ``field_name`` parameter of :meth:`.QuerySet.in_bulk` allows fetching
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|   results based on any unique model field.
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| 
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| * :meth:`.CursorWrapper.callproc()` now takes an optional dictionary of keyword
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|   parameters, if the backend supports this feature. Of Django's built-in
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|   backends, only Oracle supports it.
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| 
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| * The new :meth:`connection.execute_wrapper()
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|   <django.db.backends.base.DatabaseWrapper.execute_wrapper>` method allows
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|   :doc:`installing wrappers around execution of database queries
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|   </topics/db/instrumentation>`.
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| 
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| * The new ``filter`` argument for built-in aggregates allows :ref:`adding
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|   different conditionals <conditional-aggregation>` to multiple aggregations
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|   over the same fields or relations.
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| 
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| * Added support for expressions in :attr:`Meta.ordering
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|   <django.db.models.Options.ordering>`.
 | |
| 
 | |
| * The new ``named`` parameter of :meth:`.QuerySet.values_list` allows fetching
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|   results as named tuples.
 | |
| 
 | |
| * The new :class:`.FilteredRelation` class allows adding an ``ON`` clause to
 | |
|   querysets.
 | |
| 
 | |
| Pagination
 | |
| ~~~~~~~~~~
 | |
| 
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| * Added :meth:`Paginator.get_page() <django.core.paginator.Paginator.get_page>`
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|   to provide the documented pattern of handling invalid page numbers.
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| 
 | |
| Requests and Responses
 | |
| ~~~~~~~~~~~~~~~~~~~~~~
 | |
| 
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| * The :djadmin:`runserver` Web server supports HTTP 1.1.
 | |
| 
 | |
| Templates
 | |
| ~~~~~~~~~
 | |
| 
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| * To increase the usefulness of :meth:`.Engine.get_default` in third-party
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|   apps, it now returns the first engine if multiple ``DjangoTemplates`` engines
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|   are configured in ``TEMPLATES`` rather than raising ``ImproperlyConfigured``.
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| 
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| * Custom template tags may now accept keyword-only arguments.
 | |
| 
 | |
| Tests
 | |
| ~~~~~
 | |
| 
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| * Added threading support to :class:`~django.test.LiveServerTestCase`.
 | |
| 
 | |
| * Added settings that allow customizing the test tablespace parameters for
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|   Oracle: :setting:`DATAFILE_SIZE`, :setting:`DATAFILE_TMP_SIZE`,
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|   :setting:`DATAFILE_EXTSIZE`, and :setting:`DATAFILE_TMP_EXTSIZE`.
 | |
| 
 | |
| Validators
 | |
| ~~~~~~~~~~
 | |
| 
 | |
| * The new :class:`.ProhibitNullCharactersValidator` disallows the null
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|   character in the input of the :class:`~django.forms.CharField` form field
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|   and its subclasses. Null character input was observed from vulnerability
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|   scanning tools. Most databases silently discard null characters, but
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|   psycopg2 2.7+ raises an exception when trying to save a null character to
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|   a char/text field with PostgreSQL.
 | |
| 
 | |
| .. _backwards-incompatible-2.0:
 | |
| 
 | |
| Backwards incompatible changes in 2.0
 | |
| =====================================
 | |
| 
 | |
| Removed support for bytestrings in some places
 | |
| ----------------------------------------------
 | |
| 
 | |
| To support native Python 2 strings, older Django versions had to accept both
 | |
| bytestrings and Unicode strings. Now that Python 2 support is dropped,
 | |
| bytestrings should only be encountered around input/output boundaries (handling
 | |
| of binary fields or HTTP streams, for example). You might have to update your
 | |
| code to limit bytestring usage to a minimum, as Django no longer accepts
 | |
| bytestrings in certain code paths. Python's :option:`-b` option may help detect
 | |
| that mistake in your code.
 | |
| 
 | |
| For example, ``reverse()`` now uses ``str()`` instead of ``force_text()`` to
 | |
| coerce the ``args`` and ``kwargs`` it receives, prior to their placement in
 | |
| the URL. For bytestrings, this creates a string with an undesired ``b`` prefix
 | |
| as well as additional quotes (``str(b'foo')`` is ``"b'foo'"``). To adapt, call
 | |
| ``decode()`` on the bytestring before passing it to ``reverse()``.
 | |
| 
 | |
| Database backend API
 | |
| --------------------
 | |
| 
 | |
| This section describes changes that may be needed in third-party database
 | |
| backends.
 | |
| 
 | |
| * The ``DatabaseOperations.datetime_cast_date_sql()``,
 | |
|   ``datetime_cast_time_sql()``, ``datetime_trunc_sql()``,
 | |
|   ``datetime_extract_sql()``, and ``date_interval_sql()`` methods now return
 | |
|   only the SQL to perform the operation instead of SQL and a list of
 | |
|   parameters.
 | |
| 
 | |
| * Third-party database backends should add a ``DatabaseWrapper.display_name``
 | |
|   attribute with the name of the database that your backend works with. Django
 | |
|   may use it in various messages, such as in system checks.
 | |
| 
 | |
| * The first argument of ``SchemaEditor._alter_column_type_sql()`` is now
 | |
|   ``model`` rather than ``table``.
 | |
| 
 | |
| * The first argument of ``SchemaEditor._create_index_name()`` is now
 | |
|   ``table_name`` rather than ``model``.
 | |
| 
 | |
| * To enable ``FOR UPDATE OF`` support, set
 | |
|   ``DatabaseFeatures.has_select_for_update_of = True``. If the database
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|   requires that the arguments to ``OF`` be columns rather than tables, set
 | |
|   ``DatabaseFeatures.select_for_update_of_column = True``.
 | |
| 
 | |
| * To enable support for :class:`~django.db.models.expressions.Window`
 | |
|   expressions, set ``DatabaseFeatures.supports_over_clause`` to ``True``. You
 | |
|   may need to customize the ``DatabaseOperations.window_start_rows_start_end()``
 | |
|   and/or ``window_start_range_start_end()`` methods.
 | |
| 
 | |
| * Third-party database backends should add a
 | |
|   ``DatabaseOperations.cast_char_field_without_max_length`` attribute with the
 | |
|   database data type that will be used in the
 | |
|   :class:`~django.db.models.functions.Cast` function for a ``CharField`` if the
 | |
|   ``max_length`` argument isn't provided.
 | |
| 
 | |
| * The first argument of ``DatabaseCreation._clone_test_db()`` and
 | |
|   ``get_test_db_clone_settings()`` is now ``suffix`` rather
 | |
|   than ``number`` (in case you want to rename the signatures in your backend
 | |
|   for consistency). ``django.test`` also now passes those values as strings
 | |
|   rather than as integers.
 | |
| 
 | |
| * Third-party database backends should add a
 | |
|   ``DatabaseIntrospection.get_sequences()`` method based on the stub in
 | |
|   ``BaseDatabaseIntrospection``.
 | |
| 
 | |
| Dropped support for Oracle 11.2
 | |
| -------------------------------
 | |
| 
 | |
| The end of upstream support for Oracle 11.2 is Dec. 2020. Django 1.11 will be
 | |
| supported until April 2020 which almost reaches this date. Django 2.0
 | |
| officially supports Oracle 12.1+.
 | |
| 
 | |
| Default MySQL isolation level is read committed
 | |
| -----------------------------------------------
 | |
| 
 | |
| MySQL's default isolation level, repeatable read, may cause data loss in
 | |
| typical Django usage. To prevent that and for consistency with other databases,
 | |
| the default isolation level is now read committed. You can use the
 | |
| :setting:`DATABASES` setting to :ref:`use a different isolation level
 | |
| <mysql-isolation-level>`, if needed.
 | |
| 
 | |
| :attr:`AbstractUser.last_name <django.contrib.auth.models.User.last_name>` ``max_length`` increased to 150
 | |
| ----------------------------------------------------------------------------------------------------------
 | |
| 
 | |
| A migration for :attr:`django.contrib.auth.models.User.last_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 last names, use a custom
 | |
| form::
 | |
| 
 | |
|     from django.contrib.auth.forms import UserChangeForm
 | |
| 
 | |
|     class MyUserChangeForm(UserChangeForm):
 | |
|         last_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)
 | |
| 
 | |
| ``QuerySet.reverse()`` and ``last()`` are prohibited after slicing
 | |
| ------------------------------------------------------------------
 | |
| 
 | |
| Calling ``QuerySet.reverse()`` or ``last()`` on a sliced queryset leads to
 | |
| unexpected results due to the slice being applied after reordering. This is
 | |
| now prohibited, e.g.::
 | |
| 
 | |
|     >>> Model.objects.all()[:2].reverse()
 | |
|     Traceback (most recent call last):
 | |
|     ...
 | |
|     TypeError: Cannot reverse a query once a slice has been taken.
 | |
| 
 | |
| Form fields no longer accept optional arguments as positional arguments
 | |
| -----------------------------------------------------------------------
 | |
| 
 | |
| To help prevent runtime errors due to incorrect ordering of form field
 | |
| arguments, optional arguments of built-in form fields are no longer accepted
 | |
| as positional arguments. For example::
 | |
| 
 | |
|     forms.IntegerField(25, 10)
 | |
| 
 | |
| raises an exception and should be replaced with::
 | |
| 
 | |
|     forms.IntegerField(max_value=25, min_value=10)
 | |
| 
 | |
| ``call_command()`` validates the options it receives
 | |
| ----------------------------------------------------
 | |
| 
 | |
| ``call_command()`` now validates that the argument parser of the command being
 | |
| called defines all of the options passed to ``call_command()``.
 | |
| 
 | |
| For custom management commands that use options not created using
 | |
| ``parser.add_argument()``, add a ``stealth_options`` attribute on the command::
 | |
| 
 | |
|     class MyCommand(BaseCommand):
 | |
|         stealth_options = ('option_name', ...)
 | |
| 
 | |
| Indexes no longer accept positional arguments
 | |
| ---------------------------------------------
 | |
| 
 | |
| For example::
 | |
| 
 | |
|     models.Index(['headline', '-pub_date'], 'index_name')
 | |
| 
 | |
| raises an exception and should be replaced with::
 | |
| 
 | |
|     models.Index(fields=['headline', '-pub_date'], name='index_name')
 | |
| 
 | |
| Foreign key constraints are now enabled on SQLite
 | |
| -------------------------------------------------
 | |
| 
 | |
| This will appear as a backwards-incompatible change (``IntegrityError:
 | |
| FOREIGN KEY constraint failed``) if attempting to save an existing model
 | |
| instance that's violating a foreign key constraint.
 | |
| 
 | |
| Foreign keys are now created with ``DEFERRABLE INITIALLY DEFERRED`` instead of
 | |
| ``DEFERRABLE IMMEDIATE``. Thus, tables may need to be rebuilt to recreate
 | |
| foreign keys with the new definition, particularly if you're using a pattern
 | |
| like this::
 | |
| 
 | |
|     from django.db import transaction
 | |
| 
 | |
|     with transaction.atomic():
 | |
|         Book.objects.create(author_id=1)
 | |
|         Author.objects.create(id=1)
 | |
| 
 | |
| If you don't recreate the foreign key as ``DEFERRED``, the first ``create()``
 | |
| would fail now that foreign key constraints are enforced.
 | |
| 
 | |
| Backup your database first! After upgrading to Django 2.0, you can then
 | |
| rebuild tables using a script similar to this::
 | |
| 
 | |
|     from django.apps import apps
 | |
|     from django.db import connection
 | |
| 
 | |
|     for app in apps.get_app_configs():
 | |
|         for model in app.get_models(include_auto_created=True):
 | |
|             if model._meta.managed and not (model._meta.proxy or model._meta.swapped):
 | |
|                 for base in model.__bases__:
 | |
|                     if hasattr(base, '_meta'):
 | |
|                         base._meta.local_many_to_many = []
 | |
|                 model._meta.local_many_to_many = []
 | |
|                 with connection.schema_editor() as editor:
 | |
|                     editor._remake_table(model)
 | |
| 
 | |
| This script hasn't received extensive testing and needs adaption for various
 | |
| cases such as multiple databases. Feel free to contribute improvements.
 | |
| 
 | |
| In addition, because of a table alteration limitation of SQLite, it's prohibited
 | |
| to perform :class:`~django.db.migrations.operations.RenameModel` and
 | |
| :class:`~django.db.migrations.operations.RenameField` operations on models or
 | |
| fields referenced by other models in a transaction. In order to allow migrations
 | |
| containing these operations to be applied, you must set the
 | |
| ``Migration.atomic`` attribute to ``False``.
 | |
| 
 | |
| Miscellaneous
 | |
| -------------
 | |
| 
 | |
| * The ``SessionAuthenticationMiddleware`` class is removed. It provided no
 | |
|   functionality since session authentication is unconditionally enabled in
 | |
|   Django 1.10.
 | |
| 
 | |
| * The default HTTP error handlers (``handler404``, etc.) are now callables
 | |
|   instead of dotted Python path strings. Django favors callable references
 | |
|   since they provide better performance and debugging experience.
 | |
| 
 | |
| * :class:`~django.views.generic.base.RedirectView` no longer silences
 | |
|   ``NoReverseMatch`` if the ``pattern_name`` doesn't exist.
 | |
| 
 | |
| * When :setting:`USE_L10N` is off, :class:`~django.forms.FloatField` and
 | |
|   :class:`~django.forms.DecimalField` now respect :setting:`DECIMAL_SEPARATOR`
 | |
|   and :setting:`THOUSAND_SEPARATOR` during validation. For example, with the
 | |
|   settings::
 | |
| 
 | |
|      USE_L10N = False
 | |
|      USE_THOUSAND_SEPARATOR = True
 | |
|      DECIMAL_SEPARATOR = ','
 | |
|      THOUSAND_SEPARATOR = '.'
 | |
| 
 | |
|   an input of ``"1.345"`` is now converted to ``1345`` instead of ``1.345``.
 | |
| 
 | |
| * Subclasses of :class:`~django.contrib.auth.models.AbstractBaseUser` are no
 | |
|   longer required to implement ``get_short_name()`` and ``get_full_name()``.
 | |
|   (The base implementations that raise ``NotImplementedError`` are removed.)
 | |
|   ``django.contrib.admin`` uses these methods if implemented but doesn't
 | |
|   require them. Third-party apps that use these methods may want to adopt a
 | |
|   similar approach.
 | |
| 
 | |
| * The ``FIRST_DAY_OF_WEEK`` and ``NUMBER_GROUPING`` format settings are now
 | |
|   kept as integers in JavaScript and JSON i18n view outputs.
 | |
| 
 | |
| * :meth:`~django.test.TransactionTestCase.assertNumQueries` now ignores
 | |
|   connection configuration queries. Previously, if a test opened a new database
 | |
|   connection, those queries could be included as part of the
 | |
|   ``assertNumQueries()`` count.
 | |
| 
 | |
| * The default size of the Oracle test tablespace is increased from 20M to 50M
 | |
|   and the default autoextend size is increased from 10M to 25M.
 | |
| 
 | |
| * To improve performance when streaming large result sets from the database,
 | |
|   :meth:`.QuerySet.iterator` now fetches 2000 rows at a time instead of 100.
 | |
|   The old behavior can be restored using the ``chunk_size`` parameter. For
 | |
|   example::
 | |
| 
 | |
|       Book.objects.iterator(chunk_size=100)
 | |
| 
 | |
| * Providing unknown package names in the ``packages`` argument of the
 | |
|   :class:`~django.views.i18n.JavaScriptCatalog` view now raises ``ValueError``
 | |
|   instead of passing silently.
 | |
| 
 | |
| * A model instance's primary key now appears in the default ``Model.__str__()``
 | |
|   method, e.g. ``Question object (1)``.
 | |
| 
 | |
| * ``makemigrations`` now detects changes to the model field ``limit_choices_to``
 | |
|   option. Add this to your existing migrations or accept an auto-generated
 | |
|   migration for fields that use it.
 | |
| 
 | |
| * Performing queries that require :ref:`automatic spatial transformations
 | |
|   <automatic-spatial-transformations>` now raises ``NotImplementedError``
 | |
|   on MySQL instead of silently using non-transformed geometries.
 | |
| 
 | |
| * ``django.core.exceptions.DjangoRuntimeWarning`` is removed. It was only used
 | |
|   in the cache backend as an intermediate class in ``CacheKeyWarning``'s
 | |
|   inheritance of ``RuntimeWarning``.
 | |
| 
 | |
| * Renamed ``BaseExpression._output_field`` to ``output_field``. You may need
 | |
|   to update custom expressions.
 | |
| 
 | |
| * In older versions, forms and formsets combine their ``Media`` with widget
 | |
|   ``Media`` by concatenating the two. The combining now tries to :ref:`preserve
 | |
|   the relative order of elements in each list <form-media-asset-order>`.
 | |
|   ``MediaOrderConflictWarning`` is issued if the order can't be preserved.
 | |
| 
 | |
| * ``django.contrib.gis.gdal.OGRException`` is removed. It's been an alias for
 | |
|   ``GDALException`` since Django 1.8.
 | |
| 
 | |
| * Support for GEOS 3.3.x is dropped.
 | |
| 
 | |
| * The way data is selected for ``GeometryField`` is changed to improve
 | |
|   performance, and in raw SQL queries, those fields must now be wrapped in
 | |
|   ``connection.ops.select``. See the :ref:`Raw queries note<gis-raw-sql>` in
 | |
|   the GIS tutorial for an example.
 | |
| 
 | |
| .. _deprecated-features-2.0:
 | |
| 
 | |
| Features deprecated in 2.0
 | |
| ==========================
 | |
| 
 | |
| ``context`` argument of ``Field.from_db_value()`` and ``Expression.convert_value()``
 | |
| ------------------------------------------------------------------------------------
 | |
| 
 | |
| The ``context`` argument of ``Field.from_db_value()`` and
 | |
| ``Expression.convert_value()`` is unused as it's always an empty dictionary.
 | |
| The signature of both methods is now::
 | |
| 
 | |
|     (self, value, expression, connection)
 | |
| 
 | |
| instead of::
 | |
| 
 | |
|     (self, value, expression, connection, context)
 | |
| 
 | |
| Support for the old signature in custom fields and expressions remains until
 | |
| Django 3.0.
 | |
| 
 | |
| Miscellaneous
 | |
| -------------
 | |
| 
 | |
| * The ``django.db.backends.postgresql_psycopg2`` module is deprecated in favor
 | |
|   of ``django.db.backends.postgresql``. It's been an alias since Django 1.9.
 | |
|   This only affects code that imports from the module directly. The
 | |
|   ``DATABASES`` setting can still use
 | |
|   ``'django.db.backends.postgresql_psycopg2'``, though you can simplify that by
 | |
|   using the ``'django.db.backends.postgresql'`` name added in Django 1.9.
 | |
| 
 | |
| * ``django.shortcuts.render_to_response()`` is deprecated in favor of
 | |
|   :func:`django.shortcuts.render`. ``render()`` takes the same arguments
 | |
|   except that it also requires a ``request``.
 | |
| 
 | |
| * The ``DEFAULT_CONTENT_TYPE`` setting is deprecated. It doesn't interact well
 | |
|   with third-party apps and is obsolete since HTML5 has mostly superseded
 | |
|   XHTML.
 | |
| 
 | |
| * ``HttpRequest.xreadlines()`` is deprecated in favor of iterating over the
 | |
|   request.
 | |
| 
 | |
| * The ``field_name`` keyword argument to :meth:`.QuerySet.earliest` and
 | |
|   :meth:`.QuerySet.latest` is deprecated in favor of passing the field
 | |
|   names as arguments. Write ``.earliest('pub_date')`` instead of
 | |
|   ``.earliest(field_name='pub_date')``.
 | |
| 
 | |
| .. _removed-features-2.0:
 | |
| 
 | |
| Features removed in 2.0
 | |
| =======================
 | |
| 
 | |
| These features have reached the end of their deprecation cycle and are removed
 | |
| in Django 2.0.
 | |
| 
 | |
| See :ref:`deprecated-features-1.9` for details on these changes, including how
 | |
| to remove usage of these features.
 | |
| 
 | |
| * The ``weak`` argument to ``django.dispatch.signals.Signal.disconnect()`` is
 | |
|   removed.
 | |
| 
 | |
| * ``django.db.backends.base.BaseDatabaseOperations.check_aggregate_support()``
 | |
|   is removed.
 | |
| 
 | |
| * The ``django.forms.extras`` package is removed.
 | |
| 
 | |
| * The ``assignment_tag`` helper is removed.
 | |
| 
 | |
| * The ``host`` argument to ``SimpleTestCase.assertsRedirects()`` is removed.
 | |
|   The compatibility layer which allows absolute URLs to be considered equal to
 | |
|   relative ones when the path is identical is also removed.
 | |
| 
 | |
| * ``Field.rel`` and ``Field.remote_field.to`` are removed.
 | |
| 
 | |
| * The ``on_delete`` argument for ``ForeignKey`` and ``OneToOneField`` is now
 | |
|   required in models and migrations. Consider squashing migrations so that you
 | |
|   have fewer of them to update.
 | |
| 
 | |
| * ``django.db.models.fields.add_lazy_relation()`` is removed.
 | |
| 
 | |
| * When time zone support is enabled, database backends that don't support time
 | |
|   zones no longer convert aware datetimes to naive values in UTC anymore when
 | |
|   such values are passed as parameters to SQL queries executed outside of the
 | |
|   ORM, e.g. with ``cursor.execute()``.
 | |
| 
 | |
| * ``django.contrib.auth.tests.utils.skipIfCustomUser()`` is removed.
 | |
| 
 | |
| * The ``GeoManager`` and ``GeoQuerySet`` classes are removed.
 | |
| 
 | |
| * The ``django.contrib.gis.geoip`` module is removed.
 | |
| 
 | |
| * The ``supports_recursion`` check for template loaders is removed from:
 | |
| 
 | |
|   * ``django.template.engine.Engine.find_template()``
 | |
|   * ``django.template.loader_tags.ExtendsNode.find_template()``
 | |
|   * ``django.template.loaders.base.Loader.supports_recursion()``
 | |
|   * ``django.template.loaders.cached.Loader.supports_recursion()``
 | |
| 
 | |
| * The ``load_template`` and ``load_template_sources`` template loader methods
 | |
|   are removed.
 | |
| 
 | |
| * The ``template_dirs`` argument for template loaders is removed:
 | |
| 
 | |
|   * ``django.template.loaders.base.Loader.get_template()``
 | |
|   * ``django.template.loaders.cached.Loader.cache_key()``
 | |
|   * ``django.template.loaders.cached.Loader.get_template()``
 | |
|   * ``django.template.loaders.cached.Loader.get_template_sources()``
 | |
|   * ``django.template.loaders.filesystem.Loader.get_template_sources()``
 | |
| 
 | |
| * ``django.template.loaders.base.Loader.__call__()`` is removed.
 | |
| 
 | |
| * Support for custom error views that don't accept an ``exception`` parameter
 | |
|   is removed.
 | |
| 
 | |
| * The ``mime_type`` attribute of ``django.utils.feedgenerator.Atom1Feed`` and
 | |
|   ``django.utils.feedgenerator.RssFeed`` is removed.
 | |
| 
 | |
| * The ``app_name`` argument to ``include()`` is removed.
 | |
| 
 | |
| * Support for passing a 3-tuple (including ``admin.site.urls``) as the first
 | |
|   argument to ``include()`` is removed.
 | |
| 
 | |
| * Support for setting a URL instance namespace without an application namespace
 | |
|   is removed.
 | |
| 
 | |
| * ``Field._get_val_from_obj()`` is removed.
 | |
| 
 | |
| * ``django.template.loaders.eggs.Loader`` is removed.
 | |
| 
 | |
| * The ``current_app`` parameter to the ``contrib.auth`` function-based views is
 | |
|   removed.
 | |
| 
 | |
| * The ``callable_obj`` keyword argument to
 | |
|   ``SimpleTestCase.assertRaisesMessage()`` is removed.
 | |
| 
 | |
| * Support for the ``allow_tags`` attribute on ``ModelAdmin`` methods is
 | |
|   removed.
 | |
| 
 | |
| * The ``enclosure`` keyword argument to ``SyndicationFeed.add_item()`` is
 | |
|   removed.
 | |
| 
 | |
| * The ``django.template.loader.LoaderOrigin`` and
 | |
|   ``django.template.base.StringOrigin`` aliases for
 | |
|   ``django.template.base.Origin`` are removed.
 | |
| 
 | |
| See :ref:`deprecated-features-1.10` for details on these changes.
 | |
| 
 | |
| * The ``makemigrations --exit`` option is removed.
 | |
| 
 | |
| * Support for direct assignment to a reverse foreign key or many-to-many
 | |
|   relation is removed.
 | |
| 
 | |
| * The ``get_srid()`` and ``set_srid()`` methods of
 | |
|   ``django.contrib.gis.geos.GEOSGeometry`` are removed.
 | |
| 
 | |
| * The ``get_x()``, ``set_x()``, ``get_y()``, ``set_y()``, ``get_z()``, and
 | |
|   ``set_z()`` methods of ``django.contrib.gis.geos.Point`` are removed.
 | |
| 
 | |
| * The ``get_coords()`` and ``set_coords()`` methods of
 | |
|   ``django.contrib.gis.geos.Point`` are removed.
 | |
| 
 | |
| * The ``cascaded_union`` property of ``django.contrib.gis.geos.MultiPolygon``
 | |
|   is removed.
 | |
| 
 | |
| * ``django.utils.functional.allow_lazy()`` is removed.
 | |
| 
 | |
| * The ``shell --plain`` option is removed.
 | |
| 
 | |
| * The ``django.core.urlresolvers`` module is removed in favor of its new
 | |
|   location, ``django.urls``.
 | |
| 
 | |
| * ``CommaSeparatedIntegerField`` is removed, except for support in historical
 | |
|   migrations.
 | |
| 
 | |
| * The template ``Context.has_key()`` method is removed.
 | |
| 
 | |
| * Support for the ``django.core.files.storage.Storage.accessed_time()``,
 | |
|   ``created_time()``, and ``modified_time()`` methods is removed.
 | |
| 
 | |
| * Support for query lookups using the model name when
 | |
|   ``Meta.default_related_name`` is set is removed.
 | |
| 
 | |
| * The MySQL ``__search`` lookup is removed.
 | |
| 
 | |
| * The shim for supporting custom related manager classes without a
 | |
|   ``_apply_rel_filters()`` method is removed.
 | |
| 
 | |
| * Using ``User.is_authenticated()`` and ``User.is_anonymous()`` as methods
 | |
|   rather than properties is no longer supported.
 | |
| 
 | |
| * The ``Model._meta.virtual_fields`` attribute is removed.
 | |
| 
 | |
| * The keyword arguments ``virtual_only`` in ``Field.contribute_to_class()`` and
 | |
|   ``virtual`` in ``Model._meta.add_field()`` are removed.
 | |
| 
 | |
| * The ``javascript_catalog()`` and ``json_catalog()`` views are removed.
 | |
| 
 | |
| * ``django.contrib.gis.utils.precision_wkt()`` is removed.
 | |
| 
 | |
| * In multi-table inheritance, implicit promotion of a ``OneToOneField`` to a
 | |
|   ``parent_link`` is removed.
 | |
| 
 | |
| * Support for ``Widget._format_value()`` is removed.
 | |
| 
 | |
| * ``FileField`` methods ``get_directory_name()`` and ``get_filename()`` are
 | |
|   removed.
 | |
| 
 | |
| * The ``mark_for_escaping()`` function and the classes it uses: ``EscapeData``,
 | |
|   ``EscapeBytes``, ``EscapeText``, ``EscapeString``, and ``EscapeUnicode`` are
 | |
|   removed.
 | |
| 
 | |
| * The ``escape`` filter now uses ``django.utils.html.conditional_escape()``.
 | |
| 
 | |
| * ``Manager.use_for_related_fields`` is removed.
 | |
| 
 | |
| * Model ``Manager`` inheritance follows MRO inheritance rules. The requirement
 | |
|   to use ``Meta.manager_inheritance_from_future`` to opt-in to the behavior is
 | |
|   removed.
 | |
| 
 | |
| * Support for old-style middleware using ``settings.MIDDLEWARE_CLASSES`` is
 | |
|   removed.
 |