django/docs/releases/1.7.txt

============================================
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 </internals/deprecation>`, 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 </internals/release-process>`, 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</topics/migrations>`,
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 renamed to
  :data:`~django.db.models.signals.pre_migrate` and
  :data:`~django.db.models.signals.post_migrate` respectively. The
  ``create_models``/``created_models`` argument has also been deprecated.

* 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).

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() <django.db.models.query.QuerySet.as_manager>`
class method has been added to :ref:`create Manager with QuerySet methods
<create-manager-with-queryset-methods>`.

Using a custom manager when traversing reverse relations
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

It is now possible to :ref:`specify a custom manager
<using-custom-reverse-manager>` when traversing a reverse relationship.

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
<default-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-<app_name>`` and ``model-<model_name>``
  classes in their ``<body>`` tag to allow customizing the CSS per app or per
  model.

* The admin changelist cells now have a ``field-<field_name>`` 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()
  <django.contrib.admin.ModelAdmin.get_fields>` method may be overridden to
  customize the value of :attr:`ModelAdmin.fields
  <django.contrib.admin.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
  <django.contrib.admin.ModelAdmin.list_display_links>` ``= None`` to disable
  links on the change list page grid.

: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()
  <django.contrib.auth.forms.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.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.

: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<django.contrib.sitemaps>` 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.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``).

Email
^^^^^

* :func:`~django.core.mail.send_mail` now accepts an ``html_message``
  parameter for sending a multipart ``text/plain`` and ``text/html`` email.

File Uploads
^^^^^^^^^^^^

* The new :attr:`UploadedFile.content_type_extra
  <django.core.files.uploadedfile.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.

Forms
^^^^^

* The ``<label>`` and ``<input>`` tags rendered by
  :class:`~django.forms.RadioSelect` and
  :class:`~django.forms.CheckboxSelectMultiple` when looping over the radio
  buttons or checkboxes now include ``for`` and ``id`` attributes, respectively.
  Each radio button or checkbox includes an ``id_for_label`` attribute to
  output the element's ID.

* :attr:`Field.choices<django.db.models.Field.choices>` now allows you to
  customize the "empty choice" label by including a tuple with an empty string
  or ``None`` for the key and the custom label as the value. The default blank
  option ``"----------"`` will be omitted in this case.

* :class:`~django.forms.MultiValueField` allows optional subfields by setting
  the ``require_all_fields`` argument to ``False``. The ``required`` attribute
  for each individual field will be respected, and a new ``incomplete``
  validation error will be raised when any required fields are empty.

* The :meth:`~django.forms.Form.clean` method on a form no longer needs to
  return ``self.cleaned_data``. If it does return a changed dictionary then
  that will still be used.

* :attr:`SelectDateWidget.months
  <django.forms.extras.widgets.SelectDateWidget.months>` can be used to
  customize the wording of the months displayed in the select widget.

* The ``min_num`` and ``validate_min`` parameters were added to
  :func:`~django.forms.formsets.formset_factory` to allow validating
  a minimum number of submitted forms.

Internationalization
^^^^^^^^^^^^^^^^^^^^

* The :attr:`django.middleware.locale.LocaleMiddleware.response_redirect_class`
  attribute allows you to customize the redirects issued by the middleware.

Management Commands
^^^^^^^^^^^^^^^^^^^

* The :djadminopt:`--no-color` option for ``django-admin.py`` allows you to
  disable the colorization of management command output.

Models
^^^^^^

* The :meth:`QuerySet.update_or_create()
  <django.db.models.query.QuerySet.update_or_create>` method was added.

* The new :attr:`~django.db.models.Options.default_permissions` model
  ``Meta`` option allows you to customize (or disable) creation of the default
  add, change, and delete permissions.

* :attr:`~django.db.models.Options.app_label` is no longer required for models
  that are defined in a ``models`` package within an app.

* Explicit :class:`~django.db.models.OneToOneField` for
  :ref:`multi-table-inheritance` are now discovered in abstract classes.

* Is it now possible to avoid creating a backward relation for
  :class:`~django.db.models.OneToOneField` by setting its
  :attr:`~django.db.models.ForeignKey.related_name` to
  `'+'` or ending it with `'+'`.

Signals
^^^^^^^

* The ``enter`` argument was added to the
  :data:`~django.test.signals.setting_changed` signal.

Templates
^^^^^^^^^

* The :meth:`Context.push() <django.template.Context.push>` method now returns
  a context manager which automatically calls :meth:`pop()
  <django.template.Context.pop>` upon exiting the ``with`` statement.
  Additionally, :meth:`push() <django.template.Context.push>` now accepts
  parameters that are passed to the ``dict`` constructor used to build the new
  context level.

* The :ttag:`widthratio` template tag now accepts an "as" parameter to capture
  the result in a variable.

* The :ttag:`include` template tag will now also accept anything with a
  ``render()`` method (such as a ``Template``) as an argument. String
  arguments will be looked up using
  :func:`~django.template.loader.get_template` as always.

* It is now possible to :ttag:`include` templates recursively.

* Template objects now have an origin attribute set when
  :setting:`TEMPLATE_DEBUG` is ``True``. This allows template origins to be
  inspected and logged outside of the ``django.template`` infrastructure.

* ``TypeError`` exceptions are not longer silenced when raised during the
  rendering of a template.

* The following functions now accept a ``dirs`` parameter which is a list or
  tuple to override :setting:`TEMPLATE_DIRS`:

  * :func:`django.template.loader.get_template()`
  * :func:`django.template.loader.select_template()`
  * :func:`django.shortcuts.render()`
  * :func:`django.shortcuts.render_to_response()`

* The :tfilter:`time` filter now accepts timzone-related :ref:`format
  specifiers <date-and-time-formatting-specifiers>` ``'e'``, ``'O'`` , ``'T'``
  and ``'Z'`` and is able to digest :ref:`time-zone-aware
  <naive_vs_aware_datetimes>` ``datetime`` instances performing the expected
  rendering.

Tests
^^^^^

* :class:`~django.test.runner.DiscoverRunner` has two new attributes,
  :attr:`~django.test.runner.DiscoverRunner.test_suite` and
  :attr:`~django.test.runner.DiscoverRunner.test_runner`, which facilitate
  overriding the way tests are collected and run.

* The ``fetch_redirect_response`` argument was added to
  :meth:`~django.test.SimpleTestCase.assertRedirects`. Since the test
  client can't fetch externals URLs, this allows you to use ``assertRedirects``
  with redirects that aren't part of your Django app.

Backwards incompatible changes in 1.7
=====================================

.. warning::

    In addition to the changes outlined in this section, be sure to review the
    :doc:`deprecation plan </internals/deprecation>` for any features that
    have been removed. If you haven't updated your code within the
    deprecation timeline for a given feature, its removal may appear as a
    backwards incompatible change.

allow_syncdb/allow_migrate
~~~~~~~~~~~~~~~~~~~~~~~~~~

While Django will still look at ``allow_syncdb`` methods even though they
should be renamed to ``allow_migrate``, there is a subtle difference in which
models get passed to these methods.

For apps with migrations, ``allow_migrate`` will now get passed
:ref:`historical models <historical-models>`, which are special versioned models
without custom attributes, methods or managers. Make sure your ``allow_migrate``
methods are only referring to fields or other items in ``model._meta``.

Passing ``None`` to ``Manager.db_manager()``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In previous versions of Django, it was possible to use
``db_manager(using=None)`` on a model manager instance to obtain a manager
instance using default routing behavior, overriding any manually specified
database routing. In Django 1.7, a value of ``None`` passed to db_manager will
produce a router that *retains* any manually assigned database routing -- the
manager will *not* be reset. This was necessary to resolve an inconsistency in
the way routing information cascaded over joins. See `Ticket #13724`_ for more
details.

.. _Ticket #13724: https://code.djangoproject.com/ticket/13724

pytz may be required
~~~~~~~~~~~~~~~~~~~~

If your project handles datetimes before 1970 or after 2037 and Django raises
a :exc:`~exceptions.ValueError` when encountering them, you will have to
install pytz_. You may be affected by this problem if you use Django's time
zone-related date formats or :mod:`django.contrib.syndication`.

.. _pytz: https://pypi.python.org/pypi/pytz/

Miscellaneous
~~~~~~~~~~~~~

* The :meth:`django.core.files.uploadhandler.FileUploadHandler.new_file()`
  method is now passed an additional ``content_type_extra`` parameter. If you
  have a custom :class:`~django.core.files.uploadhandler.FileUploadHandler`
  that implements ``new_file()``, be sure it accepts this new parameter.

* :class:`ModelFormSet<django.forms.models.BaseModelFormSet>`’s no longer
  delete instances when ``save(commit=False)`` is called. See
  :attr:`~django.forms.formsets.BaseFormSet.can_delete` for instructions on how
  to manually delete objects from deleted forms.

* Loading empty fixtures emits a ``RuntimeWarning`` rather than raising
  :class:`~django.core.management.CommandError`.

* :func:`django.contrib.staticfiles.views.serve` will now raise an
  :exc:`~django.http.Http404` exception instead of
  :exc:`~django.core.exceptions.ImproperlyConfigured` when :setting:`DEBUG`
  is ``False``. This change removes the need to conditionally add the view to
  your root URLconf, which in turn makes it safe to reverse by name. It also
  removes the ability for visitors to generate spurious HTTP 500 errors by
  requesting static files that don't exist or haven't been collected yet.

* The :meth:`django.db.models.Model.__eq__` method is now defined in a
  way where instances of a proxy model and its base model are considered
  equal when primary keys match. Previously only instances of exact same
  class were considered equal on primary key match.

* The :meth:`django.db.models.Model.__eq__` method has changed such that
  two ``Model`` instances without primary key values won't be considered
  equal (unless they are the same instance).

* The :meth:`django.db.models.Model.__hash__` will now raise ``TypeError``
  when called on an instance without a primary key value. This is done to
  avoid mutable ``__hash__`` values in containers.

* :class:`~django.db.models.AutoField` columns in SQLite databases will now be
  created using the ``AUTOINCREMENT`` option, which guarantees monotonic
  increments. This will cause primary key numbering behavior to change on
  SQLite, becoming consistent with most other SQL databases. This will only
  apply to newly created tables. If you have a database created with an older
  version of Django, you will need to migrate it to take advantage of this
  feature. For example, you could do the following:

  #) Use :djadmin:`dumpdata` to save your data.
  #) Rename the existing database file (keep it as a backup).
  #) Run :djadmin:`migrate` to create the updated schema.
  #) Use :djadmin:`loaddata` to import the fixtures you exported in (1).

* ``django.contrib.auth.models.AbstractUser`` no longer defines a
  :meth:`~django.db.models.Model.get_absolute_url()` method. The old definition
  returned  ``"/users/%s/" % urlquote(self.username)`` which was arbitrary
  since applications may or may not define such a url in ``urlpatterns``.
  Define a ``get_absolute_url()`` method on your own custom user object or use
  :setting:`ABSOLUTE_URL_OVERRIDES` if you want a URL for your user.

* The static asset-serving functionality of the
  :class:`django.test.LiveServerTestCase` class has been simplified: Now it's
  only able to serve content already present in :setting:`STATIC_ROOT` when
  tests are run. The ability to transparently serve all the static assets
  (similarly to what one gets with :setting:`DEBUG = True <DEBUG>` at
  development-time) has been moved to a new class that lives in the
  ``staticfiles`` application (the one actually in charge of such feature):
  :class:`django.contrib.staticfiles.testing.StaticLiveServerCase`. In other
  words, ``LiveServerTestCase`` itself is less powerful but at the same time
  has less magic.

  Rationale behind this is removal of dependency of non-contrib code on
  contrib applications.

* The old cache URI syntax (e.g. ``"locmem://"``) is no longer supported. It
  still worked, even though it was not documented or officially supported. If
  you're still using it, please update to the current :setting:`CACHES` syntax.

Features deprecated in 1.7
==========================

``django.utils.dictconfig``/``django.utils.importlib``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

``django.utils.dictconfig`` and ``django.utils.importlib`` were copies of
respectively :mod:`logging.config` and :mod:`importlib` provided for Python
versions prior to 2.7. They have been deprecated.

``django.utils.tzinfo``
~~~~~~~~~~~~~~~~~~~~~~~

``django.utils.tzinfo`` provided two :class:`~datetime.tzinfo` subclasses,
``LocalTimezone`` and ``FixedOffset``. They've been deprecated in favor of
more correct alternatives provided by :mod:`django.utils.timezone`,
:func:`django.utils.timezone.get_default_timezone` and
:func:`django.utils.timezone.get_fixed_timezone`.

``django.utils.unittest``
~~~~~~~~~~~~~~~~~~~~~~~~~

``django.utils.unittest`` provided uniform access to the ``unittest2`` library
on all Python versions. Since ``unittest2`` became the standard library's
:mod:`unittest` module in Python 2.7, and Django 1.7 drops support for older
Python versions, this module isn't useful anymore. It has been deprecated. Use
:mod:`unittest` instead.

``django.utils.datastructures.SortedDict``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

As :class:`~collections.OrderedDict` was added to the standard library in
Python 2.7, :class:`~django.utils.datastructures.SortedDict` is no longer
needed and has been deprecated.

Custom SQL location for models package
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Previously, if models were organized in a package (``myapp/models/``) rather
than simply ``myapp/models.py``, Django would look for :ref:`initial SQL data
<initial-sql>` in ``myapp/models/sql/``. This bug has been fixed so that Django
will search ``myapp/sql/`` as documented. The old location will continue to
work until Django 1.9.

``declared_fieldsets`` attribute on ``ModelAdmin``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

``ModelAdmin.declared_fieldsets`` has been deprecated. Despite being a private
API, it will go through a regular deprecation path. This attribute was mostly
used by methods that bypassed ``ModelAdmin.get_fieldsets()`` but this was
considered a bug and has been addressed.

``syncdb``
~~~~~~~~~~

The ``syncdb`` command has been deprecated in favour of the new ``migrate``
command. ``migrate`` takes the same arguments as ``syncdb`` used to plus a few
more, so it's safe to just change the name you're calling and nothing else.

``util`` modules renamed to ``utils``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following instances of ``util.py`` in the Django codebase have been renamed
to ``utils.py`` in an effort to unify all util and utils references:

* ``django.contrib.admin.util``
* ``django.contrib.gis.db.backends.util``
* ``django.db.backends.util``
* ``django.forms.util``

``get_formsets`` method on ``ModelAdmin``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

``ModelAdmin.get_formsets`` has been deprecated in favor of the new
:meth:`~django.contrib.admin.ModelAdmin.get_formsets_with_inlines`, in order to
better handle the case of selecting showing inlines on a ``ModelAdmin``.

``IPAddressField``
~~~~~~~~~~~~~~~~~~

The :class:`django.db.models.IPAddressField` and
:class:`django.forms.IPAddressField` fields have been deprecated in favor of
:class:`django.db.models.GenericIPAddressField` and
:class:`django.forms.GenericIPAddressField`.

``BaseMemcachedCache._get_memcache_timeout`` method
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The ``BaseMemcachedCache._get_memcache_timeout()`` method has been renamed to
``get_backend_timeout()``. Despite being a private API, it will go through the
normal deprecation.