Release Notes

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The Django 1.11.x series is the last to support Python 2. The next major release, Django 2.0, will only support Python 3.5+.

Deprecating warnings are no longer loud by default

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¶

Unlike older versions of Django, Django’s own deprecation warnings are no longer displayed by default. This is consistent with Python’s default behavior.

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Also, the minimum supported version of psycopg2 is increased from 2.4.5 to 2.5.4.

LiveServerTestCase binds to port zero

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¶

Rather than taking a port range and iterating to find a free port, LiveServerTestCase binds to port zero and relies on the operating system to assign a free port. The DJANGO_LIVE_TEST_SERVER_ADDRESS environment variable is no longer used, and as it’s also no longer used, the manage.py test --liveserver option is removed.

If you need to bind LiveServerTestCase to a specific port, use the port attribute added in Django 1.11.2.

Protection against insecure redirects in django.contrib.auth and i18n views

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¶

LoginView, LogoutView (and the deprecated function-based equivalents), and set_language() protect users from being redirected to non-HTTPS next URLs when the app is running over HTTPS.

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To prevent typos from passing silently, get_or_create() and update_or_create() check that their arguments are model fields. This should be backwards-incompatible only in the fact that it might expose a bug in your project.

pytz is a required dependency and support for settings.TIME_ZONE = None is removed

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¶

To simplify Django’s timezone handling, pytz is now a required dependency. It’s automatically installed along with Django.

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from tzlocal import get_localzone

TIME_ZONE = get_localzone().zone

This works similar to settings.TIME_ZONE = None except that it also sets os.environ['TZ']. Let us know if there’s a use case where you find you can’t adapt your code to set a TIME_ZONE.

HTML changes in admin templates

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<p class="help"> is replaced with a <div> tag to allow including lists inside help text.

Read-only fields are wrapped in <div class="readonly">...</div> instead of <p>...</p> to allow any kind of HTML as the field’s content.

Changes due to the introduction of template-based widget rendering

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¶

Some undocumented classes in django.forms.widgets are removed:

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Some widget values, such as <select> options, are now localized if settings.USE_L10N=True. You could revert to the old behavior with custom widget templates that uses the localize template tag to turn off localization.

django.template.backends.django.Template.render() prohibits non-dict context

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¶

For compatibility with multiple template engines, django.template.backends.django.Template.render() (returned from high-level template loader APIs such as loader.get_template()) must receive a dictionary of context rather than Context or RequestContext. If you were passing either of the two classes, pass a dictionary instead – doing so is backwards-compatible with older versions of Django.

Model state changes in migration operations

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¶

To improve the speed of applying migrations, rendering of related models is delayed until an operation that needs them (e.g. RunPython). If you have a custom operation that works with model classes or model instances from the from_state argument in database_forwards() or database_backwards(), you must render model states using the clear_delayed_apps_cache()method as described in writing your own migration operation.

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• If no items in the feed have a pubdate or updateddate attribute, SyndicationFeed.latest_post_date() now returns the current UTC date/time, instead of a datetime without any timezone information.
• CSRF failures are logged to the django.security.csrf logger instead of django.request.

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• ALLOWED_HOSTS validation is no longer disabled when running tests.

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  If your application includes tests with custom host names, you must include those host names in ALLOWED_HOSTS. See Tests and multiple host names.
• Using a foreign key’s id (e.g. 'field_id') in ModelAdmin.list_display displays the related object’s ID.

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  Remove the _id suffix if you want the old behavior of the string representation of the object.
• In model forms, CharField with null=True now saves NULL for blank values instead of empty strings.

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• On Oracle, Model.validate_unique() no longer checks empty strings for uniqueness as the database interprets the value as NULL.
• If you subclass AbstractUser and override clean(), be sure it calls super().

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   BaseUserManager.normalize_email() is called in a new AbstractUser.clean() method so that normalization is applied in cases like model form validation.
• EmailField and URLField no longer accept the strip keyword argument.

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  Remove it because it doesn’t have an effect in older versions of Django as these fields always strip whitespace.
• The checked and selected attribute rendered by form widgets now uses HTML5 boolean syntax

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  rather than XHTML’s checked='checked' and selected='selected'.
• RelatedManager.add(), remove(), clear(), and set() now clear the prefetch_related() cache.
• To prevent possible loss of saved settings, setup_test_environment() now raises an exception if called a second time before calling teardown_test_environment().
• The undocumented DateTimeAwareJSONEncoder alias for DjangoJSONEncoder (renamed in Django 1.0) is removed.
• The cached template loader is now enabled if DEBUG is False and OPTIONS['loaders'] isn’t specified.

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  This could be backwards-incompatible if you have some template tags that aren’t thread safe.
• The prompt for stale content type deletion no longer occurs after running the migrate command. Use the new remove_stale_contenttypes command instead.
• The admin’s widget for IntegerField uses type="number" rather than type="text".

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• Conditional HTTP headers

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  are now parsed and compared according to the RFC 7232 Conditional Requests specification rather than the older RFC 2616.
• patch_response_headers() no longer adds a Last-Modified header. According to the RFC 7234#section-4.2.2, this header is useless alongside other caching headers that provide an explicit expiration time, e.g. Expires or Cache-Control.UpdateCacheMiddleware and add_never_cache_headers() call patch_response_headers() and therefore are also affected by this change.
• In the admin templates, <p class="help"> is replaced with a <div> tag to allow including lists inside help text.
• ConditionalGetMiddleware no longer sets the Date header as Web servers set that header. It also no longer sets the Content-Length header as this is now done by CommonMiddleware.
• get_model() and get_models() now raise AppRegistryNotReady if they’re called before models of all applications have been loaded.

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  Previously they only required the target application’s models to be loaded and thus could return models without all their relations set up. If you need the old behavior of get_model(), set the require_ready argument to False.
• The unused BaseCommand.can_import_settings attribute is removed.

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• The undocumented django.utils.functional.lazy_property is removed

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  .
• For consistency with non-multipart requests, MultiPartParser.parse() now leaves request.POST immutable

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  . If you’re modifying that QueryDict, you must now first copy it, e.g. request.POST.copy().
• Support for cx_Oracle < 5.2 is removed.
• Support for IPython < 1.0 is removed from the shell command.
• The signature of private API Widget.build_attrs() changed from extra_attrs=None

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  from extra_attrs=None, **kwargs to base_attrs,extra_attrs=None.
• File-like objects (e.g., StringIO and BytesIO) uploaded to an ImageField using the test client

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  now require a name attribute with a value that passes the validate_image_file_extension validator. See the note in Client.post().

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Features deprecated in 1.11¶

models.permalink() decorator

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¶

Use django.urls.reverse() instead. For example:

from django.db import models

class MyModel(models.Model):
    ...

    @models.permalink
    def url(self):
        return ('guitarist_detail', [self.slug])

becomes:

from django.db import models
from django.urls import reverse

class MyModel(models.Model):
    ...

    def url(self):
        return reverse('guitarist_detail', args=[self.slug])

Miscellaneous¶

• contrib.auth’s login() and logout() function-based views are deprecated logout() function-based views are deprecated

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  in favor of new class-based views LoginView andLogoutView.
• The unused extra_context parameter of contrib.auth.views.logout_then_login() is deprecated.
• contrib.auth’s password_change(), password_change_done(), password_reset(), password_reset_done(), password_reset_confirm(), and password_reset_complete() function-based views are deprecated

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  in favor of new class-based views PasswordChangeView, PasswordChangeDoneView, PasswordResetView, PasswordResetDoneView,PasswordResetConfirmView, and PasswordResetCompleteView.
• django.test.runner.setup_databases() is moved _databases() is moved

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  to django.test.utils.setup_databases(). The old location is deprecated.
• django.utils.translation.string_concat() is deprecated in favor of django.utils.text.format_lazy(). string_concat(*strings) can be replaced by format_lazy('{}' * len(strings), *strings).
• For the PyLibMCCache cache backend, passing pylibmc behavior settings as top-level attributes of OPTIONS is deprecated. Set them under a behaviors key within OPTIONS instead.
• The host parameter of django.utils.http.is_safe_url() is deprecated in favor of the new allowed_hosts parameter.
• Silencing exceptions raised while rendering the {% include %} template tag

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  is deprecated as the behavior is often more confusing than helpful. In Django 2.1, the exception will be raised.
• DatabaseIntrospection.get_indexes() is deprecated in favor of DatabaseIntrospection.get_constraints().
• authenticate() now passes a request argument to the authenticate() method of authentication backendsauthenticate() method of authentication backends

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  . Support for methods that don’t accept request as the first positional argument will be removed in Django 2.1.
• The USE_ETAGS setting

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  is deprecated in favor of ConditionalGetMiddleware which now adds the ETag header to responses regardless of the setting. CommonMiddleware and django.utils.cache.patch_response_headers() will no longer set ETags when the deprecation ends.
• Model._meta.has_auto_field is deprecated in favor of checking if Model._meta.auto_field is not None.
• Using regular expression groups with iLmsu# in url() is deprecated. The only group that’s useful is (?i) for case-insensitive URLs, however, case-insensitive URLs aren’t a good practice because they create multiple entries for search engines, for example. An alternative solution could be to create a handler404 that looks for uppercase characters in the URL and redirects to a lowercase equivalent.
• The renderer argument is added to the Widget.render() method.

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  Methods that don’t accept that argument will work through a deprecation period.