2.0.txt 29 KB

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  1. ============================================
  2. Django 2.0 release notes - UNDER DEVELOPMENT
  3. ============================================
  4. Welcome to Django 2.0!
  5. These release notes cover the :ref:`new features <whats-new-2.0>`, as well as
  6. some :ref:`backwards incompatible changes <backwards-incompatible-2.0>` you'll
  7. want to be aware of when upgrading from Django 1.11 or earlier. We've
  8. :ref:`dropped some features<removed-features-2.0>` that have reached the end of
  9. their deprecation cycle, and we've :ref:`begun the deprecation process for some
  10. features <deprecated-features-2.0>`.
  11. See the :doc:`/howto/upgrade-version` guide if you're updating an existing
  12. project.
  13. Python compatibility
  14. ====================
  15. Django 2.0 supports Python 3.4, 3.5, and 3.6. We **highly recommend** and only
  16. officially support the latest release of each series.
  17. The Django 1.11.x series is the last to support Python 2.7.
  18. Django 2.0 will be the last release series to support Python 3.4. If you plan
  19. a deployment of Python 3.4 beyond the end-of-life for Django 2.0 (April 2019),
  20. stick with Django 1.11 LTS (supported until April 2020) instead. Note, however,
  21. that the end-of-life for Python 3.4 is March 2019.
  22. Third-party library support for older version of Django
  23. =======================================================
  24. Following the release of Django 2.0, we suggest that third-party app authors
  25. drop support for all versions of Django prior to 1.11. At that time, you should
  26. be able to run your package's tests using ``python -Wd`` so that deprecation
  27. warnings do appear. After making the deprecation warning fixes, your app should
  28. be compatible with Django 2.0.
  29. .. _whats-new-2.0:
  30. What's new in Django 2.0
  31. ========================
  32. Minor features
  33. --------------
  34. :mod:`django.contrib.admin`
  35. ~~~~~~~~~~~~~~~~~~~~~~~~~~~
  36. * ...
  37. :mod:`django.contrib.admindocs`
  38. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  39. * ...
  40. :mod:`django.contrib.auth`
  41. ~~~~~~~~~~~~~~~~~~~~~~~~~~
  42. * The default iteration count for the PBKDF2 password hasher is increased from
  43. 36,000 to 100,000.
  44. :mod:`django.contrib.contenttypes`
  45. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  46. * ...
  47. :mod:`django.contrib.gis`
  48. ~~~~~~~~~~~~~~~~~~~~~~~~~
  49. * Added MySQL support for the
  50. :class:`~django.contrib.gis.db.models.functions.AsGeoJSON` function,
  51. :class:`~django.contrib.gis.db.models.functions.GeoHash` function,
  52. :class:`~django.contrib.gis.db.models.functions.IsValid` function,
  53. :lookup:`isvalid` lookup, and :ref:`distance lookups <distance-lookups>`.
  54. * Added the :class:`~django.contrib.gis.db.models.functions.Azimuth` and
  55. :class:`~django.contrib.gis.db.models.functions.LineLocatePoint` functions,
  56. supported on PostGIS and SpatiaLite.
  57. * Any :class:`~django.contrib.gis.geos.GEOSGeometry` imported from GeoJSON now
  58. has its SRID set.
  59. * Added the :attr:`.OSMWidget.default_zoom` attribute to customize the map's
  60. default zoom level.
  61. * Made metadata readable and editable on rasters through the
  62. :attr:`~django.contrib.gis.gdal.GDALRaster.metadata`,
  63. :attr:`~django.contrib.gis.gdal.GDALRaster.info`, and
  64. :attr:`~django.contrib.gis.gdal.GDALBand.metadata` attributes.
  65. * Allowed passing driver-specific creation options to
  66. :class:`~django.contrib.gis.gdal.GDALRaster` objects using ``papsz_options``.
  67. * Allowed creating :class:`~django.contrib.gis.gdal.GDALRaster` objects in
  68. GDAL's internal virtual filesystem. Rasters can now be :ref:`created from and
  69. converted to binary data <gdal-raster-vsimem>` in-memory.
  70. :mod:`django.contrib.messages`
  71. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  72. * ...
  73. :mod:`django.contrib.postgres`
  74. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  75. * The new ``distinct`` argument for
  76. :class:`~django.contrib.postgres.aggregates.ArrayAgg` determines if
  77. concatenated values will be distinct.
  78. * The new :class:`~django.contrib.postgres.functions.RandomUUID` database
  79. function returns a version 4 UUID. It requires use of PostgreSQL's
  80. ``pgcrypto`` extension which can be activated using the new
  81. :class:`~django.contrib.postgres.operations.CryptoExtension` migration
  82. operation.
  83. * :class:`django.contrib.postgres.indexes.GinIndex` now supports the
  84. ``fastupdate`` and ``gin_pending_list_limit`` parameters.
  85. * The new :class:`~django.contrib.postgres.indexes.GistIndex` class allows
  86. creating ``GiST`` indexes in the database. The new
  87. :class:`~django.contrib.postgres.operations.BtreeGistExtension` migration
  88. operation installs the ``btree_gist`` extension to add support for operator
  89. classes that aren't built-in.
  90. :mod:`django.contrib.redirects`
  91. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  92. * ...
  93. :mod:`django.contrib.sessions`
  94. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  95. * ...
  96. :mod:`django.contrib.sitemaps`
  97. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  98. * Added the ``protocol`` keyword argument to the
  99. :class:`~django.contrib.sitemaps.GenericSitemap` constructor.
  100. :mod:`django.contrib.sites`
  101. ~~~~~~~~~~~~~~~~~~~~~~~~~~~
  102. * ...
  103. :mod:`django.contrib.staticfiles`
  104. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  105. * ...
  106. :mod:`django.contrib.syndication`
  107. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  108. * ...
  109. Cache
  110. ~~~~~
  111. * ...
  112. CSRF
  113. ~~~~
  114. * ...
  115. Database backends
  116. ~~~~~~~~~~~~~~~~~
  117. * ...
  118. Email
  119. ~~~~~
  120. * ...
  121. File Storage
  122. ~~~~~~~~~~~~
  123. * :meth:`File.open() <django.core.files.File.open>` can be used as a context
  124. manager, e.g. ``with file.open() as f:``.
  125. File Uploads
  126. ~~~~~~~~~~~~
  127. * ...
  128. Forms
  129. ~~~~~
  130. * The new ``date_attrs`` and ``time_attrs`` arguments for
  131. :class:`~django.forms.SplitDateTimeWidget` and
  132. :class:`~django.forms.SplitHiddenDateTimeWidget` allow specifying different
  133. HTML attributes for the ``DateInput`` and ``TimeInput`` (or hidden)
  134. subwidgets.
  135. * The new :meth:`Form.errors.get_json_data()
  136. <django.forms.Form.errors.get_json_data>` method returns form errors as
  137. a dictionary suitable for including in a JSON response.
  138. Generic Views
  139. ~~~~~~~~~~~~~
  140. * The new :attr:`.ContextMixin.extra_context` attribute allows adding context
  141. in ``View.as_view()``.
  142. Internationalization
  143. ~~~~~~~~~~~~~~~~~~~~
  144. * ...
  145. Management Commands
  146. ~~~~~~~~~~~~~~~~~~~
  147. * :djadmin:`inspectdb` now translates MySQL's unsigned integer columns to
  148. ``PositiveIntegerField`` or ``PositiveSmallIntegerField``.
  149. * The new :option:`makemessages --add-location` option controls the comment
  150. format in PO files.
  151. * :djadmin:`loaddata` can now :ref:`read from stdin <loading-fixtures-stdin>`.
  152. * The new :option:`diffsettings --output` option allows formatting the output
  153. in a unified diff format.
  154. * On Oracle, :djadmin:`inspectdb` can now introspect ``AutoField`` if the
  155. column is created as an identity column.
  156. * On MySQL, :djadmin:`dbshell` now supports client-side TLS certificates.
  157. Migrations
  158. ~~~~~~~~~~
  159. * The new :option:`squashmigrations --squashed-name` option allows naming
  160. the squashed migration.
  161. Models
  162. ~~~~~~
  163. * The new :class:`~django.db.models.functions.StrIndex` database function
  164. finds the starting index of a string inside another string.
  165. * On Oracle, ``AutoField`` and ``BigAutoField`` are now created as `identity
  166. columns`_.
  167. .. _`identity columns`: https://docs.oracle.com/database/121/DRDAA/migr_tools_feat.htm#DRDAA109
  168. * The new ``chunk_size`` parameter of :meth:`.QuerySet.iterator` controls the
  169. number of rows fetched by the Python database client when streaming results
  170. from the database. For databases that don't support server-side cursors, it
  171. controls the number of results Django fetches from the database adapter.
  172. * :meth:`.QuerySet.earliest`, :meth:`.QuerySet.latest`, and
  173. :attr:`Meta.get_latest_by <django.db.models.Options.get_latest_by>` now
  174. allow ordering by several fields.
  175. * Added the :class:`~django.db.models.functions.datetime.ExtractQuarter`
  176. function to extract the quarter from :class:`~django.db.models.DateField` and
  177. :class:`~django.db.models.DateTimeField`, and exposed it through the
  178. :lookup:`quarter` lookup.
  179. * Added the :class:`~django.db.models.functions.datetime.TruncQuarter`
  180. function to truncate :class:`~django.db.models.DateField` and
  181. :class:`~django.db.models.DateTimeField` to the first day of a quarter.
  182. * Added the :attr:`~django.db.models.Index.db_tablespace` parameter to
  183. class-based indexes.
  184. * If the database supports a native duration field (Oracle and PostgreSQL),
  185. :class:`~django.db.models.functions.datetime.Extract` now works with
  186. :class:`~django.db.models.DurationField`.
  187. * Added the ``of`` argument to :meth:`.QuerySet.select_for_update()`, supported
  188. on PostgreSQL and Oracle, to lock only rows from specific tables rather than
  189. all selected tables. It may be helpful particularly when
  190. :meth:`~.QuerySet.select_for_update()` is used in conjunction with
  191. :meth:`~.QuerySet.select_related()`.
  192. * The new ``field_name`` parameter of :meth:`.QuerySet.in_bulk` allows fetching
  193. results based on any unique model field.
  194. * :meth:`.CursorWrapper.callproc()` now takes an optional dictionary of keyword
  195. parameters, if the backend supports this feature. Of Django's built-in
  196. backends, only Oracle supports it.
  197. * The new ``filter`` argument for built-in aggregates allows :ref:`adding
  198. different conditionals <conditional-aggregation>` to multiple aggregations
  199. over the same fields or relations.
  200. * Added support for expressions in :attr:`Meta.ordering
  201. <django.db.models.Options.ordering>`.
  202. Pagination
  203. ~~~~~~~~~~
  204. * Added :meth:`Paginator.get_page() <django.core.paginator.Paginator.get_page>`
  205. to provide the documented pattern of handling invalid page numbers.
  206. Requests and Responses
  207. ~~~~~~~~~~~~~~~~~~~~~~
  208. * The :djadmin:`runserver` Web server supports HTTP 1.1.
  209. Serialization
  210. ~~~~~~~~~~~~~
  211. * ...
  212. Signals
  213. ~~~~~~~
  214. * ...
  215. Templates
  216. ~~~~~~~~~
  217. * To increase the usefulness of :meth:`.Engine.get_default` in third-party
  218. apps, it now returns the first engine if multiple ``DjangoTemplates`` engines
  219. are configured in ``TEMPLATES`` rather than raising ``ImproperlyConfigured``.
  220. * Custom template tags may now accept keyword-only arguments.
  221. Tests
  222. ~~~~~
  223. * Added threading support to :class:`~django.test.LiveServerTestCase`.
  224. * Added settings that allow customizing the test tablespace parameters for
  225. Oracle: :setting:`DATAFILE_SIZE`, :setting:`DATAFILE_TMP_SIZE`,
  226. :setting:`DATAFILE_EXTSIZE`, and :setting:`DATAFILE_TMP_EXTSIZE`.
  227. URLs
  228. ~~~~
  229. * ...
  230. Validators
  231. ~~~~~~~~~~
  232. * The new :class:`.ProhibitNullCharactersValidator` disallows the null
  233. character in the input of the :class:`~django.forms.CharField` form field
  234. and its subclasses. Null character input was observed from vulnerability
  235. scanning tools. Most databases silently discard null characters, but
  236. psycopg2 2.7+ raises an exception when trying to save a null character to
  237. a char/text field with PostgreSQL.
  238. .. _backwards-incompatible-2.0:
  239. Backwards incompatible changes in 2.0
  240. =====================================
  241. Removed support for bytestrings in some places
  242. ----------------------------------------------
  243. To support native Python 2 strings, older Django versions had to accept both
  244. bytestrings and unicode strings. Now that Python 2 support is dropped,
  245. bytestrings should only be encountered around input/output boundaries (handling
  246. of binary fields or HTTP streams, for example). You might have to update your
  247. code to limit bytestring usage to a minimum, as Django no longer accepts
  248. bytestrings in certain code paths.
  249. Database backend API
  250. --------------------
  251. This section describes changes that may be needed in third-party database
  252. backends.
  253. * The ``DatabaseOperations.datetime_cast_date_sql()``,
  254. ``datetime_cast_time_sql()``, ``datetime_trunc_sql()``,
  255. ``datetime_extract_sql()``, and ``date_interval_sql()`` methods now return
  256. only the SQL to perform the operation instead of SQL and a list of
  257. parameters.
  258. * Third-party database backends should add a ``DatabaseWrapper.display_name``
  259. attribute with the name of the database that your backend works with. Django
  260. may use it in various messages, such as in system checks.
  261. * The first argument of ``SchemaEditor._alter_column_type_sql()`` is now
  262. ``model`` rather than ``table``.
  263. * The first argument of ``SchemaEditor._create_index_name()`` is now
  264. ``table_name`` rather than ``model``.
  265. * To enable ``FOR UPDATE OF`` support, set
  266. ``DatabaseFeatures.has_select_for_update_of = True``. If the database
  267. requires that the arguments to ``OF`` be columns rather than tables, set
  268. ``DatabaseFeatures.select_for_update_of_column = True``.
  269. * Third-party database backends should add a
  270. ``DatabaseOperations.cast_char_field_without_max_length`` attribute with the
  271. database data type that will be used in the
  272. :class:`~django.db.models.functions.Cast` function for a ``CharField`` if the
  273. ``max_length`` argument isn't provided.
  274. Dropped support for Oracle 11.2
  275. -------------------------------
  276. The end of upstream support for Oracle 11.2 is Dec. 2020. Django 1.11 will be
  277. supported until April 2020 which almost reaches this date. Django 2.0
  278. officially supports Oracle 12.1+.
  279. Default MySQL isolation level is read committed
  280. -----------------------------------------------
  281. MySQL's default isolation level, repeatable read, may cause data loss in
  282. typical Django usage. To prevent that and for consistency with other databases,
  283. the default isolation level is now read committed. You can use the
  284. :setting:`DATABASES` setting to :ref:`use a different isolation level
  285. <mysql-isolation-level>`, if needed.
  286. :attr:`AbstractUser.last_name <django.contrib.auth.models.User.last_name>` ``max_length`` increased to 150
  287. ----------------------------------------------------------------------------------------------------------
  288. A migration for :attr:`django.contrib.auth.models.User.last_name` is included.
  289. If you have a custom user model inheriting from ``AbstractUser``, you'll need
  290. to generate and apply a database migration for your user model.
  291. If you want to preserve the 30 character limit for last names, use a custom
  292. form::
  293. from django.contrib.auth.forms import UserChangeForm
  294. class MyUserChangeForm(UserChangeForm):
  295. last_name = forms.CharField(max_length=30, required=False)
  296. If you wish to keep this restriction in the admin when editing users, set
  297. ``UserAdmin.form`` to use this form::
  298. from django.contrib.auth.admin import UserAdmin
  299. from django.contrib.auth.models import User
  300. class MyUserAdmin(UserAdmin):
  301. form = MyUserChangeForm
  302. admin.site.unregister(User)
  303. admin.site.register(User, MyUserAdmin)
  304. ``QuerySet.reverse()`` and ``last()`` are prohibited after slicing
  305. ------------------------------------------------------------------
  306. Calling ``QuerySet.reverse()`` or ``last()`` on a sliced queryset leads to
  307. unexpected results due to the slice being applied after reordering. This is
  308. now prohibited, e.g.::
  309. >>> Model.objects.all()[:2].reverse()
  310. Traceback (most recent call last):
  311. ...
  312. TypeError: Cannot reverse a query once a slice has been taken.
  313. Form fields no longer accept optional arguments as positional arguments
  314. -----------------------------------------------------------------------
  315. To help prevent runtime errors due to incorrect ordering of form field
  316. arguments, optional arguments of built-in form fields are no longer accepted
  317. as positional arguments. For example::
  318. forms.IntegerField(25, 10)
  319. raises an exception and should be replaced with::
  320. forms.IntegerField(max_value=25, min_value=10)
  321. ``call_command()`` validates the options it receives
  322. ----------------------------------------------------
  323. ``call_command()`` now validates that the argument parser of the command being
  324. called defines all of the options passed to ``call_command()``.
  325. For custom management commands that use options not created using
  326. ``parser.add_argument()``, add a ``stealth_options`` attribute on the command::
  327. class MyCommand(BaseCommand):
  328. stealth_options = ('option_name', ...)
  329. Indexes no longer accept positional arguments
  330. ---------------------------------------------
  331. For example::
  332. models.Index(['headline', '-pub_date'], 'index_name')
  333. raises an exception and should be replaced with::
  334. models.Index(fields=['headline', '-pub_date'], name='index_name')
  335. Foreign key constraints are now enabled on SQLite
  336. -------------------------------------------------
  337. This will appear as a backwards-incompatible change (``IntegrityError:
  338. FOREIGN KEY constraint failed``) if attempting to save an existing model
  339. instance that's violating a foreign key constraint.
  340. Foreign keys are now created with ``DEFERRABLE INITIALLY DEFERRED`` instead of
  341. ``DEFERRABLE IMMEDIATE``. Thus, tables may need to be rebuilt to recreate
  342. foreign keys with the new definition, particularly if you're using a pattern
  343. like this::
  344. from django.db import transaction
  345. with transaction.atomic():
  346. Book.objects.create(author_id=1)
  347. Author.objects.create(id=1)
  348. If you don't recreate the foreign key as ``DEFERRED``, the first ``create()``
  349. would fail now that foreign key constraints are enforced.
  350. Backup your database first! After upgrading to Django 2.0, you can then
  351. rebuild tables using a script similar to this::
  352. from django.apps import apps
  353. from django.db import connection
  354. for app in apps.get_app_configs():
  355. for model in app.get_models(include_auto_created=True):
  356. if model._meta.managed and not (model._meta.proxy or model._meta.swapped):
  357. for base in model.__bases__:
  358. if hasattr(base, '_meta'):
  359. base._meta.local_many_to_many = []
  360. model._meta.local_many_to_many = []
  361. with connection.schema_editor() as editor:
  362. editor._remake_table(model)
  363. This script hasn't received extensive testing and needs adaption for various
  364. cases such as multiple databases. Feel free to contribute improvements.
  365. Miscellaneous
  366. -------------
  367. * The ``SessionAuthenticationMiddleware`` class is removed. It provided no
  368. functionality since session authentication is unconditionally enabled in
  369. Django 1.10.
  370. * The default HTTP error handlers (``handler404``, etc.) are now callables
  371. instead of dotted Python path strings. Django favors callable references
  372. since they provide better performance and debugging experience.
  373. * :class:`~django.views.generic.base.RedirectView` no longer silences
  374. ``NoReverseMatch`` if the ``pattern_name`` doesn't exist.
  375. * When :setting:`USE_L10N` is off, :class:`~django.forms.FloatField` and
  376. :class:`~django.forms.DecimalField` now respect :setting:`DECIMAL_SEPARATOR`
  377. and :setting:`THOUSAND_SEPARATOR` during validation. For example, with the
  378. settings::
  379. USE_L10N = False
  380. USE_THOUSAND_SEPARATOR = True
  381. DECIMAL_SEPARATOR = ','
  382. THOUSAND_SEPARATOR = '.'
  383. an input of ``"1.345"`` is now converted to ``1345`` instead of ``1.345``.
  384. * Subclasses of :class:`~django.contrib.auth.models.AbstractBaseUser` are no
  385. longer required to implement ``get_short_name()`` and ``get_full_name()``.
  386. (The base implementations that raise ``NotImplementedError`` are removed.)
  387. ``django.contrib.admin`` uses these methods if implemented but doesn't
  388. require them. Third-party apps that use these methods may want to adopt a
  389. similar approach.
  390. * The ``FIRST_DAY_OF_WEEK`` and ``NUMBER_GROUPING`` format settings are now
  391. kept as integers in JavaScript and JSON i18n view outputs.
  392. * :meth:`~django.test.TransactionTestCase.assertNumQueries` now ignores
  393. connection configuration queries. Previously, if a test opened a new database
  394. connection, those queries could be included as part of the
  395. ``assertNumQueries()`` count.
  396. * The ``PASSWORD_RESET_TIMEOUT_DAYS`` setting is more properly respected in
  397. ``contrib.auth`` password reset. Previously, resets were allowed for one day
  398. longer than expected. For example, with the default of
  399. ``PASSWORD_RESET_TIMEOUT_DAYS = 3``, password reset tokens are now valid for
  400. 72 hours rather than 96 hours.
  401. * The default size of the Oracle test tablespace is increased from 20M to 50M
  402. and the default autoextend size is increased from 10M to 25M.
  403. * To improve performance when streaming large result sets from the database,
  404. :meth:`.QuerySet.iterator` now fetches 2000 rows at a time instead of 100.
  405. The old behavior can be restored using the ``chunk_size`` parameter. For
  406. example::
  407. Book.objects.iterator(chunk_size=100)
  408. * Providing unknown package names in the ``packages`` argument of the
  409. :class:`~django.views.i18n.JavaScriptCatalog` view now raises ``ValueError``
  410. instead of passing silently.
  411. * A model instance's primary key now appears in the default ``Model.__str__()``
  412. method, e.g. ``Question object (1)``.
  413. * ``makemigrations`` now detects changes to the model field ``limit_choices_to``
  414. option. Add this to your existing migrations or accept an auto-generated
  415. migration for fields that use it.
  416. * Performing queries that require :ref:`automatic spatial transformations
  417. <automatic-spatial-transformations>` now raises ``NotImplementedError``
  418. on MySQL instead of silently using non-transformed geometries.
  419. * ``django.core.exceptions.DjangoRuntimeWarning`` is removed. It was only used
  420. in the cache backend as an intermediate class in ``CacheKeyWarning``'s
  421. inheritance of ``RuntimeWarning``.
  422. * Renamed ``BaseExpression._output_field`` to ``output_field``. You may need
  423. to update custom expressions.
  424. * In older versions, forms and formsets combine their ``Media`` with widget
  425. ``Media`` by concatenating the two. The combining now tries to :ref:`preserve
  426. the relative order of elements in each list <form-media-asset-order>`.
  427. ``MediaOrderConflictWarning`` is issued if the order can't be preserved.
  428. * ``django.contrib.gis.gdal.OGRException`` is removed. It's been an alias for
  429. ``GDALException`` since Django 1.8.
  430. .. _deprecated-features-2.0:
  431. Features deprecated in 2.0
  432. ==========================
  433. ``context`` argument of ``Field.from_db_value()`` and ``Expression.convert_value()``
  434. ------------------------------------------------------------------------------------
  435. The ``context`` argument of ``Field.from_db_value()`` and
  436. ``Expression.convert_value()`` is unused as it's always an empty dictionary.
  437. The signature of both methods is now::
  438. (self, value, expression, connection)
  439. instead of::
  440. (self, value, expression, connection, context)
  441. Support for the old signature in custom fields and expressions remains until
  442. Django 3.0.
  443. Miscellaneous
  444. -------------
  445. * The ``django.db.backends.postgresql_psycopg2`` module is deprecated in favor
  446. of ``django.db.backends.postgresql``. It's been an alias since Django 1.9.
  447. This only affects code that imports from the module directly. The
  448. ``DATABASES`` setting can still use
  449. ``'django.db.backends.postgresql_psycopg2'``, though you can simplify that by
  450. using the ``'django.db.backends.postgresql'`` name added in Django 1.9.
  451. * ``django.shortcuts.render_to_response()`` is deprecated in favor of
  452. :func:`django.shortcuts.render`. ``render()`` takes the same arguments
  453. except that is also requires a ``request``.
  454. * The ``DEFAULT_CONTENT_TYPE`` setting is deprecated. It doesn't interact well
  455. well with third-party apps and is obsolete since HTML5 has mostly superseded
  456. XHTML.
  457. * ``HttpRequest.xreadlines()`` is deprecated in favor of iterating over the
  458. request.
  459. * The ``field_name`` keyword argument to :meth:`.QuerySet.earliest` and
  460. :meth:`.QuerySet.latest` is deprecated in favor of passing the field
  461. names as arguments. Write ``.earliest('pub_date')`` instead of
  462. ``.earliest(field_name='pub_date')``.
  463. .. _removed-features-2.0:
  464. Features removed in 2.0
  465. =======================
  466. These features have reached the end of their deprecation cycle and are removed
  467. in Django 2.0. See :ref:`deprecated-features-1.9` and
  468. :ref:`deprecated-features-1.10` for details, including how to remove usage of
  469. these features.
  470. * The ``weak`` argument to ``django.dispatch.signals.Signal.disconnect()`` is
  471. removed.
  472. * ``django.db.backends.base.BaseDatabaseOperations.check_aggregate_support()``
  473. is removed.
  474. * The ``django.forms.extras`` package is removed.
  475. * The ``assignment_tag`` helper is removed.
  476. * The ``host`` argument to ``SimpleTestCase.assertsRedirects()`` is removed.
  477. The compatibility layer which allows absolute URLs to be considered equal to
  478. relative ones when the path is identical is also removed.
  479. * ``Field.rel`` and ``Field.remote_field.to`` are removed.
  480. * The ``on_delete`` argument for ``ForeignKey`` and ``OneToOneField`` are now
  481. required.
  482. * ``django.db.models.fields.add_lazy_relation()`` is removed.
  483. * When time zone support is enabled, database backends that don't support time
  484. zones no longer convert aware datetimes to naive values in UTC anymore when
  485. such values are passed as parameters to SQL queries executed outside of the
  486. ORM, e.g. with ``cursor.execute()``.
  487. * ``django.contrib.auth.tests.utils.skipIfCustomUser()`` is removed.
  488. * The ``GeoManager`` and ``GeoQuerySet`` classes are removed.
  489. * The ``django.contrib.gis.geoip`` module is removed.
  490. * The ``supports_recursion`` check for template loaders is removed from:
  491. * ``django.template.engine.Engine.find_template()``
  492. * ``django.template.loader_tags.ExtendsNode.find_template()``
  493. * ``django.template.loaders.base.Loader.supports_recursion()``
  494. * ``django.template.loaders.cached.Loader.supports_recursion()``
  495. * The ``load_template`` and ``load_template_sources`` template loader methods
  496. are removed.
  497. * The ``template_dirs`` argument for template loaders is removed:
  498. * ``django.template.loaders.base.Loader.get_template()``
  499. * ``django.template.loaders.cached.Loader.cache_key()``
  500. * ``django.template.loaders.cached.Loader.get_template()``
  501. * ``django.template.loaders.cached.Loader.get_template_sources()``
  502. * ``django.template.loaders.filesystem.Loader.get_template_sources()``
  503. * ``django.template.loaders.base.Loader.__call__()`` is removed.
  504. * Support for custom error views that don't accept an ``exception`` parameter
  505. is removed.
  506. * The ``mime_type`` attribute of ``django.utils.feedgenerator.Atom1Feed`` and
  507. ``django.utils.feedgenerator.RssFeed`` is removed.
  508. * The ``app_name`` argument to ``include()`` is removed.
  509. * Support for passing a 3-tuple (including ``admin.site.urls``) as the first
  510. argument to ``include()`` is removed.
  511. * Support for setting a URL instance namespace without an application namespace
  512. is removed.
  513. * ``Field._get_val_from_obj()`` is removed.
  514. * ``django.template.loaders.eggs.Loader`` is removed.
  515. * The ``current_app`` parameter to the ``contrib.auth`` function-based views is
  516. removed.
  517. * The ``callable_obj`` keyword argument to
  518. ``SimpleTestCase.assertRaisesMessage()`` is removed.
  519. * Support for the ``allow_tags`` attribute on ``ModelAdmin`` methods is
  520. removed.
  521. * The ``enclosure`` keyword argument to ``SyndicationFeed.add_item()`` is
  522. removed.
  523. * The ``django.template.loader.LoaderOrigin`` and
  524. ``django.template.base.StringOrigin`` aliases for
  525. ``django.template.base.Origin`` are removed.
  526. * The ``makemigrations --exit`` option is removed.
  527. * Support for direct assignment to a reverse foreign key or many-to-many
  528. relation is removed.
  529. * The ``get_srid()`` and ``set_srid()`` methods of
  530. ``django.contrib.gis.geos.GEOSGeometry`` are removed.
  531. * The ``get_x()``, ``set_x()``, ``get_y()``, ``set_y()``, ``get_z()``, and
  532. ``set_z()`` methods of ``django.contrib.gis.geos.Point`` are removed.
  533. * The ``get_coords()`` and ``set_coords()`` methods of
  534. ``django.contrib.gis.geos.Point`` are removed.
  535. * The ``cascaded_union`` property of ``django.contrib.gis.geos.MultiPolygon``
  536. is removed.
  537. * ``django.utils.functional.allow_lazy()`` is removed.
  538. * The ``shell --plain`` option is removed.
  539. * The ``django.core.urlresolvers`` module is removed.
  540. * ``CommaSeparatedIntegerField`` is removed, except for support in historical
  541. migrations.
  542. * The template ``Context.has_key()`` method is removed.
  543. * Support for the ``django.core.files.storage.Storage.accessed_time()``,
  544. ``created_time()``, and ``modified_time()`` methods is removed.
  545. * Support for query lookups using the model name when
  546. ``Meta.default_related_name`` is set is removed.
  547. * The MySQL ``__search`` lookup is removed.
  548. * The shim for supporting custom related manager classes without a
  549. ``_apply_rel_filters()`` method is removed.
  550. * Using ``User.is_authenticated()`` and ``User.is_anonymous()`` as methods
  551. rather than properties is no longer supported.
  552. * The ``Model._meta.virtual_fields`` attribute is removed.
  553. * The keyword arguments ``virtual_only`` in ``Field.contribute_to_class()`` and
  554. ``virtual`` in ``Model._meta.add_field()`` are removed.
  555. * The ``javascript_catalog()`` and ``json_catalog()`` views are removed.
  556. * ``django.contrib.gis.utils.precision_wkt()`` is removed.
  557. * In multi-table inheritance, implicit promotion of a ``OneToOneField`` to a
  558. ``parent_link`` is removed.
  559. * Support for ``Widget._format_value()`` is removed.
  560. * ``FileField`` methods ``get_directory_name()`` and ``get_filename()`` are
  561. removed.
  562. * The ``mark_for_escaping()`` function and the classes it uses: ``EscapeData``,
  563. ``EscapeBytes``, ``EscapeText``, ``EscapeString``, and ``EscapeUnicode`` are
  564. removed.
  565. * The ``escape`` filter now uses ``django.utils.html.conditional_escape()``.
  566. * ``Manager.use_for_related_fields`` is removed.
  567. * Model ``Manager`` inheritance follows MRO inheritance rules. The requirement
  568. to use ``Meta.manager_inheritance_from_future`` to opt-in to the behavior is
  569. removed.
  570. * Support for old-style middleware using ``settings.MIDDLEWARE_CLASSES`` is
  571. removed.