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. Requests and Responses
  203. ~~~~~~~~~~~~~~~~~~~~~~
  204. * The :djadmin:`runserver` Web server supports HTTP 1.1.
  205. Serialization
  206. ~~~~~~~~~~~~~
  207. * ...
  208. Signals
  209. ~~~~~~~
  210. * ...
  211. Templates
  212. ~~~~~~~~~
  213. * To increase the usefulness of :meth:`.Engine.get_default` in third-party
  214. apps, it now returns the first engine if multiple ``DjangoTemplates`` engines
  215. are configured in ``TEMPLATES`` rather than raising ``ImproperlyConfigured``.
  216. * Custom template tags may now accept keyword-only arguments.
  217. Tests
  218. ~~~~~
  219. * Added threading support to :class:`~django.test.LiveServerTestCase`.
  220. * Added settings that allow customizing the test tablespace parameters for
  221. Oracle: :setting:`DATAFILE_SIZE`, :setting:`DATAFILE_TMP_SIZE`,
  222. :setting:`DATAFILE_EXTSIZE`, and :setting:`DATAFILE_TMP_EXTSIZE`.
  223. URLs
  224. ~~~~
  225. * ...
  226. Validators
  227. ~~~~~~~~~~
  228. * The new :class:`.ProhibitNullCharactersValidator` disallows the null
  229. character in the input of the :class:`~django.forms.CharField` form field
  230. and its subclasses. Null character input was observed from vulnerability
  231. scanning tools. Most databases silently discard null characters, but
  232. psycopg2 2.7+ raises an exception when trying to save a null character to
  233. a char/text field with PostgreSQL.
  234. .. _backwards-incompatible-2.0:
  235. Backwards incompatible changes in 2.0
  236. =====================================
  237. Removed support for bytestrings in some places
  238. ----------------------------------------------
  239. To support native Python 2 strings, older Django versions had to accept both
  240. bytestrings and unicode strings. Now that Python 2 support is dropped,
  241. bytestrings should only be encountered around input/output boundaries (handling
  242. of binary fields or HTTP streams, for example). You might have to update your
  243. code to limit bytestring usage to a minimum, as Django no longer accepts
  244. bytestrings in certain code paths.
  245. Database backend API
  246. --------------------
  247. This section describes changes that may be needed in third-party database
  248. backends.
  249. * The ``DatabaseOperations.datetime_cast_date_sql()``,
  250. ``datetime_cast_time_sql()``, ``datetime_trunc_sql()``,
  251. ``datetime_extract_sql()``, and ``date_interval_sql()`` methods now return
  252. only the SQL to perform the operation instead of SQL and a list of
  253. parameters.
  254. * Third-party database backends should add a ``DatabaseWrapper.display_name``
  255. attribute with the name of the database that your backend works with. Django
  256. may use it in various messages, such as in system checks.
  257. * The first argument of ``SchemaEditor._alter_column_type_sql()`` is now
  258. ``model`` rather than ``table``.
  259. * The first argument of ``SchemaEditor._create_index_name()`` is now
  260. ``table_name`` rather than ``model``.
  261. * To enable ``FOR UPDATE OF`` support, set
  262. ``DatabaseFeatures.has_select_for_update_of = True``. If the database
  263. requires that the arguments to ``OF`` be columns rather than tables, set
  264. ``DatabaseFeatures.select_for_update_of_column = True``.
  265. * Third-party database backends should add a
  266. ``DatabaseOperations.cast_char_field_without_max_length`` attribute with the
  267. database data type that will be used in the
  268. :class:`~django.db.models.functions.Cast` function for a ``CharField`` if the
  269. ``max_length`` argument isn't provided.
  270. Dropped support for Oracle 11.2
  271. -------------------------------
  272. The end of upstream support for Oracle 11.2 is Dec. 2020. Django 1.11 will be
  273. supported until April 2020 which almost reaches this date. Django 2.0
  274. officially supports Oracle 12.1+.
  275. Default MySQL isolation level is read committed
  276. -----------------------------------------------
  277. MySQL's default isolation level, repeatable read, may cause data loss in
  278. typical Django usage. To prevent that and for consistency with other databases,
  279. the default isolation level is now read committed. You can use the
  280. :setting:`DATABASES` setting to :ref:`use a different isolation level
  281. <mysql-isolation-level>`, if needed.
  282. :attr:`AbstractUser.last_name <django.contrib.auth.models.User.last_name>` ``max_length`` increased to 150
  283. ----------------------------------------------------------------------------------------------------------
  284. A migration for :attr:`django.contrib.auth.models.User.last_name` is included.
  285. If you have a custom user model inheriting from ``AbstractUser``, you'll need
  286. to generate and apply a database migration for your user model.
  287. If you want to preserve the 30 character limit for last names, use a custom
  288. form::
  289. from django.contrib.auth.forms import UserChangeForm
  290. class MyUserChangeForm(UserChangeForm):
  291. last_name = forms.CharField(max_length=30, required=False)
  292. If you wish to keep this restriction in the admin when editing users, set
  293. ``UserAdmin.form`` to use this form::
  294. from django.contrib.auth.admin import UserAdmin
  295. from django.contrib.auth.models import User
  296. class MyUserAdmin(UserAdmin):
  297. form = MyUserChangeForm
  298. admin.site.unregister(User)
  299. admin.site.register(User, MyUserAdmin)
  300. ``QuerySet.reverse()`` and ``last()`` are prohibited after slicing
  301. ------------------------------------------------------------------
  302. Calling ``QuerySet.reverse()`` or ``last()`` on a sliced queryset leads to
  303. unexpected results due to the slice being applied after reordering. This is
  304. now prohibited, e.g.::
  305. >>> Model.objects.all()[:2].reverse()
  306. Traceback (most recent call last):
  307. ...
  308. TypeError: Cannot reverse a query once a slice has been taken.
  309. Form fields no longer accept optional arguments as positional arguments
  310. -----------------------------------------------------------------------
  311. To help prevent runtime errors due to incorrect ordering of form field
  312. arguments, optional arguments of built-in form fields are no longer accepted
  313. as positional arguments. For example::
  314. forms.IntegerField(25, 10)
  315. raises an exception and should be replaced with::
  316. forms.IntegerField(max_value=25, min_value=10)
  317. ``call_command()`` validates the options it receives
  318. ----------------------------------------------------
  319. ``call_command()`` now validates that the argument parser of the command being
  320. called defines all of the options passed to ``call_command()``.
  321. For custom management commands that use options not created using
  322. ``parser.add_argument()``, add a ``stealth_options`` attribute on the command::
  323. class MyCommand(BaseCommand):
  324. stealth_options = ('option_name', ...)
  325. Indexes no longer accept positional arguments
  326. ---------------------------------------------
  327. For example::
  328. models.Index(['headline', '-pub_date'], 'index_name')
  329. raises an exception and should be replaced with::
  330. models.Index(fields=['headline', '-pub_date'], name='index_name')
  331. Foreign key constraints are now enabled on SQLite
  332. -------------------------------------------------
  333. This will appear as a backwards-incompatible change (``IntegrityError:
  334. FOREIGN KEY constraint failed``) if attempting to save an existing model
  335. instance that's violating a foreign key constraint.
  336. Foreign keys are now created with ``DEFERRABLE INITIALLY DEFERRED`` instead of
  337. ``DEFERRABLE IMMEDIATE``. Thus, tables may need to be rebuilt to recreate
  338. foreign keys with the new definition, particularly if you're using a pattern
  339. like this::
  340. from django.db import transaction
  341. with transaction.atomic():
  342. Book.objects.create(author_id=1)
  343. Author.objects.create(id=1)
  344. If you don't recreate the foreign key as ``DEFERRED``, the first ``create()``
  345. would fail now that foreign key constraints are enforced.
  346. Backup your database first! After upgrading to Django 2.0, you can then
  347. rebuild tables using a script similar to this::
  348. from django.apps import apps
  349. from django.db import connection
  350. for app in apps.get_app_configs():
  351. for model in app.get_models(include_auto_created=True):
  352. if model._meta.managed and not (model._meta.proxy or model._meta.swapped):
  353. for base in model.__bases__:
  354. if hasattr(base, '_meta'):
  355. base._meta.local_many_to_many = []
  356. model._meta.local_many_to_many = []
  357. with connection.schema_editor() as editor:
  358. editor._remake_table(model)
  359. This script hasn't received extensive testing and needs adaption for various
  360. cases such as multiple databases. Feel free to contribute improvements.
  361. Miscellaneous
  362. -------------
  363. * The ``SessionAuthenticationMiddleware`` class is removed. It provided no
  364. functionality since session authentication is unconditionally enabled in
  365. Django 1.10.
  366. * The default HTTP error handlers (``handler404``, etc.) are now callables
  367. instead of dotted Python path strings. Django favors callable references
  368. since they provide better performance and debugging experience.
  369. * :class:`~django.views.generic.base.RedirectView` no longer silences
  370. ``NoReverseMatch`` if the ``pattern_name`` doesn't exist.
  371. * When :setting:`USE_L10N` is off, :class:`~django.forms.FloatField` and
  372. :class:`~django.forms.DecimalField` now respect :setting:`DECIMAL_SEPARATOR`
  373. and :setting:`THOUSAND_SEPARATOR` during validation. For example, with the
  374. settings::
  375. USE_L10N = False
  376. USE_THOUSAND_SEPARATOR = True
  377. DECIMAL_SEPARATOR = ','
  378. THOUSAND_SEPARATOR = '.'
  379. an input of ``"1.345"`` is now converted to ``1345`` instead of ``1.345``.
  380. * Subclasses of :class:`~django.contrib.auth.models.AbstractBaseUser` are no
  381. longer required to implement ``get_short_name()`` and ``get_full_name()``.
  382. (The base implementations that raise ``NotImplementedError`` are removed.)
  383. ``django.contrib.admin`` uses these methods if implemented but doesn't
  384. require them. Third-party apps that use these methods may want to adopt a
  385. similar approach.
  386. * The ``FIRST_DAY_OF_WEEK`` and ``NUMBER_GROUPING`` format settings are now
  387. kept as integers in JavaScript and JSON i18n view outputs.
  388. * :meth:`~django.test.TransactionTestCase.assertNumQueries` now ignores
  389. connection configuration queries. Previously, if a test opened a new database
  390. connection, those queries could be included as part of the
  391. ``assertNumQueries()`` count.
  392. * The ``PASSWORD_RESET_TIMEOUT_DAYS`` setting is more properly respected in
  393. ``contrib.auth`` password reset. Previously, resets were allowed for one day
  394. longer than expected. For example, with the default of
  395. ``PASSWORD_RESET_TIMEOUT_DAYS = 3``, password reset tokens are now valid for
  396. 72 hours rather than 96 hours.
  397. * The default size of the Oracle test tablespace is increased from 20M to 50M
  398. and the default autoextend size is increased from 10M to 25M.
  399. * To improve performance when streaming large result sets from the database,
  400. :meth:`.QuerySet.iterator` now fetches 2000 rows at a time instead of 100.
  401. The old behavior can be restored using the ``chunk_size`` parameter. For
  402. example::
  403. Book.objects.iterator(chunk_size=100)
  404. * Providing unknown package names in the ``packages`` argument of the
  405. :class:`~django.views.i18n.JavaScriptCatalog` view now raises ``ValueError``
  406. instead of passing silently.
  407. * A model instance's primary key now appears in the default ``Model.__str__()``
  408. method, e.g. ``Question object (1)``.
  409. * ``makemigrations`` now detects changes to the model field ``limit_choices_to``
  410. option. Add this to your existing migrations or accept an auto-generated
  411. migration for fields that use it.
  412. * Performing queries that require :ref:`automatic spatial transformations
  413. <automatic-spatial-transformations>` now raises ``NotImplementedError``
  414. on MySQL instead of silently using non-transformed geometries.
  415. * ``django.core.exceptions.DjangoRuntimeWarning`` is removed. It was only used
  416. in the cache backend as an intermediate class in ``CacheKeyWarning``'s
  417. inheritance of ``RuntimeWarning``.
  418. * Renamed ``BaseExpression._output_field`` to ``output_field``. You may need
  419. to update custom expressions.
  420. * In older versions, forms and formsets combine their ``Media`` with widget
  421. ``Media`` by concatenating the two. The combining now tries to :ref:`preserve
  422. the relative order of elements in each list <form-media-asset-order>`.
  423. ``MediaOrderConflictWarning`` is issued if the order can't be preserved.
  424. * ``django.contrib.gis.gdal.OGRException`` is removed. It's been an alias for
  425. ``GDALException`` since Django 1.8.
  426. .. _deprecated-features-2.0:
  427. Features deprecated in 2.0
  428. ==========================
  429. ``context`` argument of ``Field.from_db_value()`` and ``Expression.convert_value()``
  430. ------------------------------------------------------------------------------------
  431. The ``context`` argument of ``Field.from_db_value()`` and
  432. ``Expression.convert_value()`` is unused as it's always an empty dictionary.
  433. The signature of both methods is now::
  434. (self, value, expression, connection)
  435. instead of::
  436. (self, value, expression, connection, context)
  437. Support for the old signature in custom fields and expressions remains until
  438. Django 3.0.
  439. Miscellaneous
  440. -------------
  441. * The ``django.db.backends.postgresql_psycopg2`` module is deprecated in favor
  442. of ``django.db.backends.postgresql``. It's been an alias since Django 1.9.
  443. This only affects code that imports from the module directly. The
  444. ``DATABASES`` setting can still use
  445. ``'django.db.backends.postgresql_psycopg2'``, though you can simplify that by
  446. using the ``'django.db.backends.postgresql'`` name added in Django 1.9.
  447. * ``django.shortcuts.render_to_response()`` is deprecated in favor of
  448. :func:`django.shortcuts.render`. ``render()`` takes the same arguments
  449. except that is also requires a ``request``.
  450. * The ``DEFAULT_CONTENT_TYPE`` setting is deprecated. It doesn't interact well
  451. well with third-party apps and is obsolete since HTML5 has mostly superseded
  452. XHTML.
  453. * ``HttpRequest.xreadlines()`` is deprecated in favor of iterating over the
  454. request.
  455. * The ``field_name`` keyword argument to :meth:`.QuerySet.earliest` and
  456. :meth:`.QuerySet.latest` is deprecated in favor of passing the field
  457. names as arguments. Write ``.earliest('pub_date')`` instead of
  458. ``.earliest(field_name='pub_date')``.
  459. .. _removed-features-2.0:
  460. Features removed in 2.0
  461. =======================
  462. These features have reached the end of their deprecation cycle and are removed
  463. in Django 2.0. See :ref:`deprecated-features-1.9` and
  464. :ref:`deprecated-features-1.10` for details, including how to remove usage of
  465. these features.
  466. * The ``weak`` argument to ``django.dispatch.signals.Signal.disconnect()`` is
  467. removed.
  468. * ``django.db.backends.base.BaseDatabaseOperations.check_aggregate_support()``
  469. is removed.
  470. * The ``django.forms.extras`` package is removed.
  471. * The ``assignment_tag`` helper is removed.
  472. * The ``host`` argument to ``SimpleTestCase.assertsRedirects()`` is removed.
  473. The compatibility layer which allows absolute URLs to be considered equal to
  474. relative ones when the path is identical is also removed.
  475. * ``Field.rel`` and ``Field.remote_field.to`` are removed.
  476. * The ``on_delete`` argument for ``ForeignKey`` and ``OneToOneField`` are now
  477. required.
  478. * ``django.db.models.fields.add_lazy_relation()`` is removed.
  479. * When time zone support is enabled, database backends that don't support time
  480. zones no longer convert aware datetimes to naive values in UTC anymore when
  481. such values are passed as parameters to SQL queries executed outside of the
  482. ORM, e.g. with ``cursor.execute()``.
  483. * ``django.contrib.auth.tests.utils.skipIfCustomUser()`` is removed.
  484. * The ``GeoManager`` and ``GeoQuerySet`` classes are removed.
  485. * The ``django.contrib.gis.geoip`` module is removed.
  486. * The ``supports_recursion`` check for template loaders is removed from:
  487. * ``django.template.engine.Engine.find_template()``
  488. * ``django.template.loader_tags.ExtendsNode.find_template()``
  489. * ``django.template.loaders.base.Loader.supports_recursion()``
  490. * ``django.template.loaders.cached.Loader.supports_recursion()``
  491. * The ``load_template`` and ``load_template_sources`` template loader methods
  492. are removed.
  493. * The ``template_dirs`` argument for template loaders is removed:
  494. * ``django.template.loaders.base.Loader.get_template()``
  495. * ``django.template.loaders.cached.Loader.cache_key()``
  496. * ``django.template.loaders.cached.Loader.get_template()``
  497. * ``django.template.loaders.cached.Loader.get_template_sources()``
  498. * ``django.template.loaders.filesystem.Loader.get_template_sources()``
  499. * ``django.template.loaders.base.Loader.__call__()`` is removed.
  500. * Support for custom error views that don't accept an ``exception`` parameter
  501. is removed.
  502. * The ``mime_type`` attribute of ``django.utils.feedgenerator.Atom1Feed`` and
  503. ``django.utils.feedgenerator.RssFeed`` is removed.
  504. * The ``app_name`` argument to ``include()`` is removed.
  505. * Support for passing a 3-tuple (including ``admin.site.urls``) as the first
  506. argument to ``include()`` is removed.
  507. * Support for setting a URL instance namespace without an application namespace
  508. is removed.
  509. * ``Field._get_val_from_obj()`` is removed.
  510. * ``django.template.loaders.eggs.Loader`` is removed.
  511. * The ``current_app`` parameter to the ``contrib.auth`` function-based views is
  512. removed.
  513. * The ``callable_obj`` keyword argument to
  514. ``SimpleTestCase.assertRaisesMessage()`` is removed.
  515. * Support for the ``allow_tags`` attribute on ``ModelAdmin`` methods is
  516. removed.
  517. * The ``enclosure`` keyword argument to ``SyndicationFeed.add_item()`` is
  518. removed.
  519. * The ``django.template.loader.LoaderOrigin`` and
  520. ``django.template.base.StringOrigin`` aliases for
  521. ``django.template.base.Origin`` are removed.
  522. * The ``makemigrations --exit`` option is removed.
  523. * Support for direct assignment to a reverse foreign key or many-to-many
  524. relation is removed.
  525. * The ``get_srid()`` and ``set_srid()`` methods of
  526. ``django.contrib.gis.geos.GEOSGeometry`` are removed.
  527. * The ``get_x()``, ``set_x()``, ``get_y()``, ``set_y()``, ``get_z()``, and
  528. ``set_z()`` methods of ``django.contrib.gis.geos.Point`` are removed.
  529. * The ``get_coords()`` and ``set_coords()`` methods of
  530. ``django.contrib.gis.geos.Point`` are removed.
  531. * The ``cascaded_union`` property of ``django.contrib.gis.geos.MultiPolygon``
  532. is removed.
  533. * ``django.utils.functional.allow_lazy()`` is removed.
  534. * The ``shell --plain`` option is removed.
  535. * The ``django.core.urlresolvers`` module is removed.
  536. * ``CommaSeparatedIntegerField`` is removed, except for support in historical
  537. migrations.
  538. * The template ``Context.has_key()`` method is removed.
  539. * Support for the ``django.core.files.storage.Storage.accessed_time()``,
  540. ``created_time()``, and ``modified_time()`` methods is removed.
  541. * Support for query lookups using the model name when
  542. ``Meta.default_related_name`` is set is removed.
  543. * The MySQL ``__search`` lookup is removed.
  544. * The shim for supporting custom related manager classes without a
  545. ``_apply_rel_filters()`` method is removed.
  546. * Using ``User.is_authenticated()`` and ``User.is_anonymous()`` as methods
  547. rather than properties is no longer supported.
  548. * The ``Model._meta.virtual_fields`` attribute is removed.
  549. * The keyword arguments ``virtual_only`` in ``Field.contribute_to_class()`` and
  550. ``virtual`` in ``Model._meta.add_field()`` are removed.
  551. * The ``javascript_catalog()`` and ``json_catalog()`` views are removed.
  552. * ``django.contrib.gis.utils.precision_wkt()`` is removed.
  553. * In multi-table inheritance, implicit promotion of a ``OneToOneField`` to a
  554. ``parent_link`` is removed.
  555. * Support for ``Widget._format_value()`` is removed.
  556. * ``FileField`` methods ``get_directory_name()`` and ``get_filename()`` are
  557. removed.
  558. * The ``mark_for_escaping()`` function and the classes it uses: ``EscapeData``,
  559. ``EscapeBytes``, ``EscapeText``, ``EscapeString``, and ``EscapeUnicode`` are
  560. removed.
  561. * The ``escape`` filter now uses ``django.utils.html.conditional_escape()``.
  562. * ``Manager.use_for_related_fields`` is removed.
  563. * Model ``Manager`` inheritance follows MRO inheritance rules. The requirement
  564. to use ``Meta.manager_inheritance_from_future`` to opt-in to the behavior is
  565. removed.
  566. * Support for old-style middleware using ``settings.MIDDLEWARE_CLASSES`` is
  567. removed.