============================================ Django 1.7 release notes - UNDER DEVELOPMENT ============================================ Welcome to Django 1.7! These release notes cover the `new features`_, as well as some `backwards incompatible changes`_ you'll want to be aware of when upgrading from Django 1.6 or older versions. We've also dropped some features, which are detailed in :doc:`our deprecation plan `, and we've `begun the deprecation process for some features`_. .. _`new features`: `What's new in Django 1.7`_ .. _`backwards incompatible changes`: `Backwards incompatible changes in 1.7`_ .. _`begun the deprecation process for some features`: `Features deprecated in 1.7`_ Python compatibility ==================== Django 1.7 requires Python 2.7 or above, though we **highly recommend** the latest minor release. Support for Python 2.6 has been dropped. This change should affect only a small number of Django users, as most operating-system vendors today are shipping Python 2.7 or newer as their default version. If you're still using Python 2.6, however, you'll need to stick to Django 1.6 until you can upgrade your Python version. Per :doc:`our support policy `, Django 1.6 will continue to receive security support until the release of Django 1.8. What's new in Django 1.7 ======================== Schema migrations ~~~~~~~~~~~~~~~~~ Django now has built-in support for schema migrations. It allows models to be updated, changed, and deleted by creating migration files that represent the model changes and which can be run on any development, staging or production database. Migrations are covered in :doc:`their own documentation`, but a few of the key features are: * ``syncdb`` has been deprecated and replaced by ``migrate``. Don't worry - calls to ``syncdb`` will still work as before. * A new ``makemigrations`` command provides an easy way to autodetect changes to your models and make migrations for them. :data:`~django.db.models.signals.pre_syncdb` and :data:`~django.db.models.signals.post_syncdb` have been replaced by :data:`~django.db.models.signals.pre_migrate` and :data:`~django.db.models.signals.post_migrate` respectively. These new signals have slightly different arguments. Check the documentation for details. * The ``allow_syncdb`` method on database routers is now called ``allow_migrate``, but still performs the same function. Routers with ``allow_syncdb`` methods will still work, but that method name is deprecated and you should change it as soon as possible (nothing more than renaming is required). App-loading refactor ~~~~~~~~~~~~~~~~~~~~ Historically, Django applications were tightly linked to models. A singleton known as the "app cache" dealt with both installed applications and models. The models module was used as an identifier for applications in many APIs. As the concept of :doc:`Django applications ` matured, this code showed some shortcomings. It has been refactored into an "app registry" where models modules no longer have a central role and where it's possible to attach configuration data to applications. Improvements thus far include: * It is possible to omit ``models.py`` entirely if an application doesn't have any models. * The name of applications can be customized in the admin with the :attr:`~django.apps.AppConfig.verbose_name` of application configurations. New method on Field subclasses ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ To help power both schema migrations and composite keys, the :class:`~django.db.models.Field` API now has a new required method: ``deconstruct()``. This method takes no arguments, and returns a tuple of four items: * ``name``: The field's attribute name on its parent model, or None if it is not part of a model * ``path``: A dotted, Python path to the class of this field, including the class name. * ``args``: Positional arguments, as a list * ``kwargs``: Keyword arguments, as a dict These four values allow any field to be serialized into a file, as well as allowing the field to be copied safely, both essential parts of these new features. This change should not affect you unless you write custom Field subclasses; if you do, you may need to reimplement the ``deconstruct()`` method if your subclass changes the method signature of ``__init__`` in any way. If your field just inherits from a built-in Django field and doesn't override ``__init__``, no changes are necessary. If you do need to override ``deconstruct()``, a good place to start is the built-in Django fields (``django/db/models/fields/__init__.py``) as several fields, including ``DecimalField`` and ``DateField``, override it and show how to call the method on the superclass and simply add or remove extra arguments. Calling custom ``QuerySet`` methods from the ``Manager`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The :meth:`QuerySet.as_manager() ` class method has been added to :ref:`create Manager with QuerySet methods `. Using a custom manager when traversing reverse relations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ It is now possible to :ref:`specify a custom manager ` when traversing a reverse relationship. New ``Prefetch`` object for advanced ``prefetch_related`` operations. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The new :class:`~django.db.models.Prefetch` object allows customizing prefetch operations. You can specify the ``QuerySet`` used to traverse a given relation or customize the storage location of prefetch results. This enables things like filtering prefetched relations, calling :meth:`~django.db.models.query.QuerySet.select_related()` from a prefetched relation, or prefetching the same relation multiple times with different querysets. See :meth:`~django.db.models.query.QuerySet.prefetch_related()` for more details. Admin shortcuts support time zones ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The "today" and "now" shortcuts next to date and time input widgets in the admin are now operating in the :ref:`current time zone `. Previously, they used the browser time zone, which could result in saving the wrong value when it didn't match the current time zone on the server. In addition, the widgets now display a help message when the browser and server time zone are different, to clarify how the value inserted in the field will be interpreted. Using database cursors as context managers ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Prior to Python 2.7, database cursors could be used as a context manager. The specific backend's cursor defined the behavior of the context manager. The behavior of magic method lookups was changed with Python 2.7 and cursors were no longer usable as context managers. Django 1.7 allows a cursor to be used as a context manager that is a shortcut for the following, instead of backend specific behavior. .. code-block:: python c = connection.cursor() try: c.execute(...) finally: c.close() Minor features ~~~~~~~~~~~~~~ :mod:`django.contrib.admin` ^^^^^^^^^^^^^^^^^^^^^^^^^^^ * You can now implement :attr:`~django.contrib.admin.AdminSite.site_header`, :attr:`~django.contrib.admin.AdminSite.site_title`, and :attr:`~django.contrib.admin.AdminSite.index_title` attributes on a custom :class:`~django.contrib.admin.AdminSite` in order to easily change the admin site's page title and header text. No more needing to override templates! * Buttons in :mod:`django.contrib.admin` now use the ``border-radius`` CSS property for rounded corners rather than GIF background images. * Some admin templates now have ``app-`` and ``model-`` classes in their ```` tag to allow customizing the CSS per app or per model. * The admin changelist cells now have a ``field-`` class in the HTML to enable style customizations. * The admin's search fields can now be customized per-request thanks to the new :meth:`django.contrib.admin.ModelAdmin.get_search_fields` method. * The :meth:`ModelAdmin.get_fields() ` method may be overridden to customize the value of :attr:`ModelAdmin.fields `. * In addition to the existing ``admin.site.register`` syntax, you can use the new :func:`~django.contrib.admin.register` decorator to register a :class:`~django.contrib.admin.ModelAdmin`. * You may specify :meth:`ModelAdmin.list_display_links ` ``= None`` to disable links on the change list page grid. * You may now specify :attr:`ModelAdmin.view_on_site ` to control whether or not to display the "View on site" link. :mod:`django.contrib.auth` ^^^^^^^^^^^^^^^^^^^^^^^^^^ * Any ``**kwargs`` passed to :meth:`~django.contrib.auth.models.User.email_user()` are passed to the underlying :meth:`~django.core.mail.send_mail()` call. * The :func:`~django.contrib.auth.decorators.permission_required` decorator can take a list of permissions as well as a single permission. * You can override the new :meth:`AuthenticationForm.confirm_login_allowed() ` method to more easily customize the login policy. * :func:`django.contrib.auth.views.password_reset` takes an optional ``html_email_template_name`` parameter used to send a multipart HTML email for password resets. :mod:`django.contrib.gis` ^^^^^^^^^^^^^^^^^^^^^^^^^^ * The default OpenLayers library version included in widgets has been updated from 2.11 to 2.13. * Prepared geometries now also support the ``crosses``, ``disjoint``, ``overlaps``, ``touches`` and ``within`` predicates, if GEOS 3.3 or later is installed. :mod:`django.contrib.messages` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * The backends for :mod:`django.contrib.messages` that use cookies, will now follow the :setting:`SESSION_COOKIE_SECURE` and :setting:`SESSION_COOKIE_HTTPONLY` settings. * The :ref:`messages context processor ` now adds a dictionary of default levels under the name ``DEFAULT_MESSAGE_LEVELS``. * :class:`~django.contrib.messages.storage.base.Message` objects now have a ``level_tag`` attribute that contains the string representation of the message level. :mod:`django.contrib.redirects` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * :class:`~django.contrib.redirects.middleware.RedirectFallbackMiddleware` has two new attributes (:attr:`~django.contrib.redirects.middleware.RedirectFallbackMiddleware.response_gone_class` and :attr:`~django.contrib.redirects.middleware.RedirectFallbackMiddleware.response_redirect_class`) that specify the types of :class:`~django.http.HttpResponse` instances the middleware returns. :mod:`django.contrib.sessions` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * The ``"django.contrib.sessions.backends.cached_db"`` session backend now respects :setting:`SESSION_CACHE_ALIAS`. In previous versions, it always used the `default` cache. :mod:`django.contrib.sitemaps` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * The :mod:`sitemap framework` now makes use of :attr:`~django.contrib.sitemaps.Sitemap.lastmod` to set a ``Last-Modified`` header in the response. This makes it possible for the :class:`~django.middleware.http.ConditionalGetMiddleware` to handle conditional ``GET`` requests for sitemaps which set ``lastmod``. :mod:`django.contrib.staticfiles` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * The :ref:`static files storage classes ` may be subclassed to override the permissions that collected static files and directories receive by setting the :attr:`~django.core.files.storage.FileSystemStorage.file_permissions_mode` and :attr:`~django.core.files.storage.FileSystemStorage.directory_permissions_mode` parameters. See :djadmin:`collectstatic` for example usage. :mod:`django.contrib.syndication` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * The :class:`~django.utils.feedgenerator.Atom1Feed` syndication feed's ``updated`` element now utilizes ``updateddate`` instead of ``pubdate``, allowing the ``published`` element to be included in the feed (which relies on ``pubdate``). Cache ^^^^^ * Access to caches configured in :setting:`CACHES` is now available via :data:`django.core.cache.caches`. This dict-like object provides a different instance per thread. It supersedes :func:`django.core.cache.get_cache` which is now deprecated. * If you instanciate cache backends directly, be aware that they aren't thread-safe any more, as :data:`django.core.cache.caches` now yields different instances per thread. Email ^^^^^ * :func:`~django.core.mail.send_mail` now accepts an ``html_message`` parameter for sending a multipart ``text/plain`` and ``text/html`` email. * The SMTP :class:`~django.core.mail.backends.smtp.EmailBackend` now accepts a :attr:`~django.core.mail.backends.smtp.EmailBackend.timeout` parameter. File Uploads ^^^^^^^^^^^^ * The new :attr:`UploadedFile.content_type_extra ` attribute contains extra parameters passed to the ``content-type`` header on a file upload. * The new :setting:`FILE_UPLOAD_DIRECTORY_PERMISSIONS` setting controls the file system permissions of directories created during file upload, like :setting:`FILE_UPLOAD_PERMISSIONS` does for the files themselves. * The :attr:`FileField.upload_to ` attribute is now optional. If it is omitted or given ``None`` or an empty string, a subdirectory won't be used for storing the uploaded files. Forms ^^^^^ * The ``