Ticket #15124: 15124ticket.v2.diff

File 15124ticket.v2.diff, 51.2 KB (added by chomik, 3 years ago)

change marked as backwards incompatibile in release notes

  • docs/releases/index.txt

    8181.. toctree::
    8282   :maxdepth: 1
     84   1.4-beta-1
    8485   1.4-alpha-1
    8586   1.3-beta-1
    8687   1.3-alpha-1
  • docs/releases/1.4-beta-1.txt

     2Django 1.4 beta release notes
     5December 22, 2011.
     7Welcome to Django 1.4 beta!
     9This is the first in a series of preview/development releases leading up to
     10the eventual release of Django 1.4, scheduled for March 2012. This release is
     11primarily targeted at developers who are interested in trying out new features
     12and testing the Django codebase to help identify and resolve bugs prior to the
     13final 1.4 release.
     15As such, this release is *not* intended for production use, and any such use
     16is discouraged.
     18Django 1.4 beta includes various `new features`_ and some minor `backwards
     19incompatible changes`_. There are also some features that have been dropped,
     20which are detailed in :doc:`our deprecation plan </internals/deprecation>`,
     21and we've `begun the deprecation process for some features`_.
     23.. _new features: `What's new in Django 1.4`_
     24.. _backwards incompatible changes: `Backwards incompatible changes in 1.4`_
     25.. _begun the deprecation process for some features: `Features deprecated in 1.4`_
     27Python compatibility
     30While not a new feature, it's important to note that Django 1.4 introduces the
     31second shift in our Python compatibility policy since Django's initial public
     32debut. Django 1.2 dropped support for Python 2.3; now Django 1.4 drops support
     33for Python 2.4. As such, the minimum Python version required for Django is now
     342.5, and Django is tested and supported on Python 2.5, 2.6 and 2.7.
     36This change should affect only a small number of Django users, as most
     37operating-system vendors today are shipping Python 2.5 or newer as their default
     38version. If you're still using Python 2.4, however, you'll need to stick to
     39Django 1.3 until you can upgrade; per :doc:`our support policy
     40</internals/release-process>`, Django 1.3 will continue to receive security
     41support until the release of Django 1.5.
     43Django does not support Python 3.x at this time. A document outlining our full
     44timeline for deprecating Python 2.x and moving to Python 3.x will be published
     45before the release of Django 1.4.
     47What's new in Django 1.4
     50Support for in-browser testing frameworks
     53Django 1.4 now supports integration with in-browser testing frameworks such
     54as Selenium_ or Windmill_ thanks to the :class:`django.test.LiveServerTestCase`
     55base class, allowing you to test the interactions between your site's front and
     56back ends more comprehensively. See the
     57:class:`documentation<django.test.LiveServerTestCase>` for more details and
     58concrete examples.
     60.. _Windmill: http://www.getwindmill.com/
     61.. _Selenium: http://seleniumhq.org/
     63``SELECT FOR UPDATE`` support
     66Django 1.4 now includes a :meth:`QuerySet.select_for_update()
     67<django.db.models.query.QuerySet.select_for_update>` method which generates a
     68``SELECT ... FOR UPDATE`` SQL query. This will lock rows until the end of the
     69transaction, meaning that other transactions cannot modify or delete rows
     70matched by a ``FOR UPDATE`` query.
     72For more details, see the documentation for
     75``Model.objects.bulk_create`` in the ORM
     78This method allows for more efficient creation of multiple objects in the ORM.
     79It can provide significant performance increases if you have many objects.
     80Django makes use of this internally, meaning some operations (such as database
     81setup for test suites) have seen a performance benefit as a result.
     83See the :meth:`~django.db.models.query.QuerySet.bulk_create` docs for more
     89Similar to :meth:`~django.db.models.query.QuerySet.select_related` but with a
     90different strategy and broader scope,
     91:meth:`~django.db.models.query.QuerySet.prefetch_related` has been added to
     92:class:`~django.db.models.query.QuerySet`. This method returns a new
     93``QuerySet`` that will prefetch each of the specified related lookups in a
     94single batch as soon as the query begins to be evaluated. Unlike
     95``select_related``, it does the joins in Python, not in the database, and
     96supports many-to-many relationships,
     97:class:`~django.contrib.contenttypes.generic.GenericForeignKey` and more. This
     98allows you to fix a very common performance problem in which your code ends up
     99doing O(n) database queries (or worse) if objects on your primary ``QuerySet``
     100each have many related objects that you also need.
     102Improved password hashing
     105Django's auth system (``django.contrib.auth``) stores passwords using a one-way
     106algorithm. Django 1.3 uses the SHA1_ algorithm, but increasing processor speeds
     107and theoretical attacks have revealed that SHA1 isn't as secure as we'd like.
     108Thus, Django 1.4 introduces a new password storage system: by default Django now
     109uses the PBKDF2_ algorithm (as recommended by NIST_). You can also easily choose
     110a different algorithm (including the popular bcrypt_ algorithm). For more
     111details, see :ref:`auth_password_storage`.
     113.. _sha1: http://en.wikipedia.org/wiki/SHA1
     114.. _pbkdf2: http://en.wikipedia.org/wiki/PBKDF2
     115.. _nist: http://csrc.nist.gov/publications/nistpubs/800-132/nist-sp800-132.pdf
     116.. _bcrypt: http://en.wikipedia.org/wiki/Bcrypt
     119HTML5 Doctype
     122We've switched the admin and other bundled templates to use the HTML5
     123doctype. While Django will be careful to maintain compatibility with older
     124browsers, this change means that you can use any HTML5 features you need in
     125admin pages without having to lose HTML validity or override the provided
     126templates to change the doctype.
     128List filters in admin interface
     131Prior to Django 1.4, the :mod:`~django.contrib.admin` app allowed you to specify
     132change list filters by specifying a field lookup, but didn't allow you to create
     133custom filters. This has been rectified with a simple API (previously used
     134internally and known as "FilterSpec"). For more details, see the documentation
     135for :attr:`~django.contrib.admin.ModelAdmin.list_filter`.
     137Multiple sort in admin interface
     140The admin change list now supports sorting on multiple columns. It respects all
     141elements of the :attr:`~django.contrib.admin.ModelAdmin.ordering` attribute, and
     142sorting on multiple columns by clicking on headers is designed to mimic the
     143behavior of desktop GUIs. The
     144:meth:`~django.contrib.admin.ModelAdmin.get_ordering` method for specifying the
     145ordering dynamically (e.g. depending on the request) has also been added.
     147New ``ModelAdmin`` methods
     150A new :meth:`~django.contrib.admin.ModelAdmin.save_related` method was added to
     151:mod:`~django.contrib.admin.ModelAdmin` to ease customization of how
     152related objects are saved in the admin.
     154Two other new methods,
     155:meth:`~django.contrib.admin.ModelAdmin.get_list_display` and
     157were added to :class:`~django.contrib.admin.ModelAdmin` to enable the dynamic
     158customization of fields and links displayed on the admin change list.
     160Admin inlines respect user permissions
     163Admin inlines will now only allow those actions for which the user has
     164permission. For ``ManyToMany`` relationships with an auto-created intermediate
     165model (which does not have its own permissions), the change permission for the
     166related model determines if the user has the permission to add, change or
     167delete relationships.
     169Tools for cryptographic signing
     172Django 1.4 adds both a low-level API for signing values and a high-level API
     173for setting and reading signed cookies, one of the most common uses of
     174signing in Web applications.
     176See the :doc:`cryptographic signing </topics/signing>` docs for more
     179Cookie-based session backend
     182Django 1.4 introduces a new cookie-based backend for the session framework
     183which uses the tools for :doc:`cryptographic signing </topics/signing>` to
     184store the session data in the client's browser.
     186See the :ref:`cookie-based session backend <cookie-session-backend>` docs for
     187more information.
     189New form wizard
     192The previous ``FormWizard`` from the formtools contrib app has been
     193replaced with a new implementation based on the class-based views
     194introduced in Django 1.3. It features a pluggable storage API and doesn't
     195require the wizard to pass around hidden fields for every previous step.
     197Django 1.4 ships with a session-based storage backend and a cookie-based
     198storage backend. The latter uses the tools for
     199:doc:`cryptographic signing </topics/signing>` also introduced in
     200Django 1.4 to store the wizard's state in the user's cookies.
     202See the :doc:`form wizard </ref/contrib/formtools/form-wizard>` docs for
     203more information.
     208A lazily evaluated version of :func:`django.core.urlresolvers.reverse` was
     209added to allow using URL reversals before the project's URLConf gets loaded.
     211Translating URL patterns
     214Django 1.4 gained the ability to look for a language prefix in the URL pattern
     215when using the new :func:`~django.conf.urls.i18n.i18n_patterns` helper function.
     216Additionally, it's now possible to define translatable URL patterns using
     217:func:`~django.utils.translation.ugettext_lazy`. See
     218:ref:`url-internationalization` for more information about the language prefix
     219and how to internationalize URL patterns.
     221Contextual translation support for ``{% trans %}`` and ``{% blocktrans %}``
     224The :ref:`contextual translation<contextual-markers>` support introduced in
     225Django 1.3 via the ``pgettext`` function has been extended to the
     226:ttag:`trans` and :ttag:`blocktrans` template tags using the new ``context``
     229Customizable ``SingleObjectMixin`` URLConf kwargs
     232Two new attributes,
     236have been added to :class:`~django.views.generic.detail.SingleObjectMixin` to
     237enable the customization of URLConf keyword arguments used for single
     238object generic views.
     240Assignment template tags
     243A new :ref:`assignment_tag<howto-custom-template-tags-assignment-tags>` helper
     244function was added to ``template.Library`` to ease the creation of template
     245tags that store data in a specified context variable.
     247``*args`` and ``**kwargs`` support for template tag helper functions
     250The :ref:`simple_tag<howto-custom-template-tags-simple-tags>`,
     251:ref:`inclusion_tag <howto-custom-template-tags-inclusion-tags>` and
     252newly introduced
     253:ref:`assignment_tag<howto-custom-template-tags-assignment-tags>` template
     254helper functions may now accept any number of positional or keyword arguments.
     255For example:
     257.. code-block:: python
     259    @register.simple_tag
     260    def my_tag(a, b, *args, **kwargs):
     261        warning = kwargs['warning']
     262        profile = kwargs['profile']
     263        ...
     264        return ...
     266Then in the template any number of arguments may be passed to the template tag.
     267For example:
     269.. code-block:: html+django
     271    {% my_tag 123 "abcd" book.title warning=message|lower profile=user.profile %}
     273No wrapping of exceptions in ``TEMPLATE_DEBUG`` mode
     276In previous versions of Django, whenever the :setting:`TEMPLATE_DEBUG` setting
     277was ``True``, any exception raised during template rendering (even exceptions
     278unrelated to template syntax) were wrapped in ``TemplateSyntaxError`` and
     279re-raised. This was done in order to provide detailed template source location
     280information in the debug 500 page.
     282In Django 1.4, exceptions are no longer wrapped. Instead, the original
     283exception is annotated with the source information. This means that catching
     284exceptions from template rendering is now consistent regardless of the value of
     285:setting:`TEMPLATE_DEBUG`, and there's no need to catch and unwrap
     286``TemplateSyntaxError`` in order to catch other errors.
     288``truncatechars`` template filter
     291Added a filter which truncates a string to be no longer than the specified
     292number of characters. Truncated strings end with a translatable ellipsis
     293sequence ("..."). See the documentation for :tfilter:`truncatechars` for
     294more details.
     296``static`` template tag
     299The :mod:`staticfiles<django.contrib.staticfiles>` contrib app has a new
     300:ttag:`static<staticfiles-static>` template tag to refer to files saved with
     301the :setting:`STATICFILES_STORAGE` storage backend. It uses the storage
     302backend's ``url`` method and therefore supports advanced features such as
     303:ref:`serving files from a cloud service<staticfiles-from-cdn>`.
     305``CachedStaticFilesStorage`` storage backend
     308In addition to the `static template tag`_, the
     309:mod:`staticfiles<django.contrib.staticfiles>` contrib app now has a
     310:class:`~django.contrib.staticfiles.storage.CachedStaticFilesStorage` backend
     311which caches the files it saves (when running the :djadmin:`collectstatic`
     312management command) by appending the MD5 hash of the file's content to the
     313filename. For example, the file ``css/styles.css`` would also be saved as
     316See the :class:`~django.contrib.staticfiles.storage.CachedStaticFilesStorage`
     317docs for more information.
     319Simple clickjacking protection
     322We've added a middleware to provide easy protection against `clickjacking
     323<http://en.wikipedia.org/wiki/Clickjacking>`_ using the ``X-Frame-Options``
     324header. It's not enabled by default for backwards compatibility reasons, but
     325you'll almost certainly want to :doc:`enable it </ref/clickjacking/>` to help
     326plug that security hole for browsers that support the header.
     328CSRF improvements
     331We've made various improvements to our CSRF features, including the
     332:func:`~django.views.decorators.csrf.ensure_csrf_cookie` decorator which can
     333help with AJAX heavy sites, protection for PUT and DELETE requests, and the
     334:setting:`CSRF_COOKIE_SECURE` and :setting:`CSRF_COOKIE_PATH` settings which can
     335improve the security and usefulness of the CSRF protection. See the :doc:`CSRF
     336docs </ref/contrib/csrf>` for more information.
     338Error report filtering
     341Two new function decorators, :func:`sensitive_variables` and
     342:func:`sensitive_post_parameters`, were added to allow designating the
     343local variables and POST parameters which may contain sensitive
     344information and should be filtered out of error reports.
     346All POST parameters are now systematically filtered out of error reports for
     347certain views (``login``, ``password_reset_confirm``, ``password_change``, and
     348``add_view`` in :mod:`django.contrib.auth.views`, as well as
     349``user_change_password`` in the admin app) to prevent the leaking of sensitive
     350information such as user passwords.
     352You may override or customize the default filtering by writing a :ref:`custom
     353filter<custom-error-reports>`. For more information see the docs on
     354:ref:`Filtering error reports<filtering-error-reports>`.
     356Extended IPv6 support
     359The previously added support for IPv6 addresses when using the runserver
     360management command in Django 1.3 has now been further extended by adding
     361a :class:`~django.db.models.fields.GenericIPAddressField` model field,
     362a :class:`~django.forms.fields.GenericIPAddressField` form field and
     363the validators :data:`~django.core.validators.validate_ipv46_address` and
     366Updated default project layout and ``manage.py``
     369Django 1.4 ships with an updated default project layout and ``manage.py`` file
     370for the :djadmin:`startproject` management command. These fix some issues with
     371the previous ``manage.py`` handling of Python import paths that caused double
     372imports, trouble moving from development to deployment, and other
     373difficult-to-debug path issues.
     375The previous ``manage.py`` called functions that are now deprecated, and thus
     376projects upgrading to Django 1.4 should update their ``manage.py``. (The
     377old-style ``manage.py`` will continue to work as before until Django 1.6; in
     3781.5 it will raise ``DeprecationWarning``).
     380The new recommended ``manage.py`` file should look like this::
     382    #!/usr/bin/env python
     383    import os, sys
     385    if __name__ == "__main__":
     386        os.environ.setdefault("DJANGO_SETTINGS_MODULE", "{{ project_name }}.settings")
     388        from django.core.management import execute_from_command_line
     390        execute_from_command_line(sys.argv)
     392``{{ project_name }}`` should be replaced with the Python package name of the
     393actual project.
     395If settings, URLconfs, and apps within the project are imported or referenced
     396using the project name prefix (e.g. ``myproject.settings``, ``ROOT_URLCONF =
     397"myproject.urls"``, etc), the new ``manage.py`` will need to be moved one
     398directory up, so it is outside the project package rather than adjacent to
     399``settings.py`` and ``urls.py``.
     401For instance, with the following layout::
     403    manage.py
     404    mysite/
     405        __init__.py
     406        settings.py
     407        urls.py
     408        myapp/
     409            __init__.py
     410            models.py
     412You could import ``mysite.settings``, ``mysite.urls``, and ``mysite.myapp``,
     413but not ``settings``, ``urls``, or ``myapp`` as top-level modules.
     415Anything imported as a top-level module can be placed adjacent to the new
     416``manage.py``. For instance, to decouple "myapp" from the project module and
     417import it as just ``myapp``, place it outside the ``mysite/`` directory::
     419    manage.py
     420    myapp/
     421        __init__.py
     422        models.py
     423    mysite/
     424        __init__.py
     425        settings.py
     426        urls.py
     428If the same code is imported inconsistently (some places with the project
     429prefix, some places without it), the imports will need to be cleaned up when
     430switching to the new ``manage.py``.
     432Improved WSGI support
     435The :djadmin:`startproject` management command now adds a :file:`wsgi.py`
     436module to the initial project layout, containing a simple WSGI application that
     437can be used for :doc:`deploying with WSGI app
     440The :djadmin:`built-in development server<runserver>` now supports using an
     441externally-defined WSGI callable, so as to make it possible to run runserver
     442with the same WSGI configuration that is used for deployment. A new
     443:setting:`WSGI_APPLICATION` setting is available to configure which WSGI
     444callable :djadmin:`runserver` uses.
     446(The :djadmin:`runfcgi` management command also internally wraps the WSGI
     447callable configured via :setting:`WSGI_APPLICATION`.)
     449Custom project and app templates
     452The :djadmin:`startapp` and :djadmin:`startproject` management commands
     453got a ``--template`` option for specifying a path or URL to a custom app or
     454project template.
     456For example, Django will use the ``/path/to/my_project_template`` directory
     457when running the following command::
     459    django-admin.py startproject --template=/path/to/my_project_template myproject
     461You can also now provide a destination directory as the second
     462argument to both :djadmin:`startapp` and :djadmin:`startproject`::
     464    django-admin.py startapp myapp /path/to/new/app
     465    django-admin.py startproject myproject /path/to/new/project
     467For more information, see the :djadmin:`startapp` and :djadmin:`startproject`
     470Support for time zones
     473Django 1.4 adds :ref:`support for time zones <time-zones>`. When it's enabled,
     474Django stores date and time information in UTC in the database, uses time
     475zone-aware datetime objects internally, and translates them to the end user's
     476time zone in templates and forms.
     478Reasons for using this feature include:
     480- Customizing date and time display for users around the world.
     481- Storing datetimes in UTC for database portability and interoperability.
     482  (This argument doesn't apply to PostgreSQL, because it already stores
     483  timestamps with time zone information in Django 1.3.)
     484- Avoiding data corruption problems around DST transitions.
     486Time zone support is enabled by default in new projects created with
     487:djadmin:`startproject`. If you want to use this feature in an existing
     488project, there is a :ref:`migration guide <time-zones-migration-guide>`.
     490Minor features
     493Django 1.4 also includes several smaller improvements worth noting:
     495* A more usable stacktrace in the technical 500 page: frames in the
     496  stack trace which reference Django's code are dimmed out, while
     497  frames in user code are slightly emphasized. This change makes it
     498  easier to scan a stacktrace for issues in user code.
     500* :doc:`Tablespace support </topics/db/tablespaces>` in PostgreSQL.
     502* Customizable names for :meth:`~django.template.Library.simple_tag`.
     504* In the documentation, a helpful :doc:`security overview </topics/security>`
     505  page.
     507* The :func:`django.contrib.auth.models.check_password` function has been moved
     508  to the :mod:`django.contrib.auth.utils` module. Importing it from the old
     509  location will still work, but you should update your imports.
     511* The :djadmin:`collectstatic` management command gained a ``--clear`` option
     512  to delete all files at the destination before copying or linking the static
     513  files.
     515* It is now possible to load fixtures containing forward references when using
     516  MySQL with the InnoDB database engine.
     518* A new 403 response handler has been added as
     519  ``'django.views.defaults.permission_denied'``. You can set your own handler by
     520  setting the value of :data:`django.conf.urls.handler403`. See the
     521  documentation about :ref:`the 403 (HTTP Forbidden) view<http_forbidden_view>`
     522  for more information.
     524* The :ttag:`trans` template tag now takes an optional ``as`` argument to
     525  be able to retrieve a translation string without displaying it but setting
     526  a template context variable instead.
     528* The :ttag:`if` template tag now supports ``{% elif %}`` clauses.
     530* A new plain text version of the HTTP 500 status code internal error page
     531  served when :setting:`DEBUG` is ``True`` is now sent to the client when
     532  Django detects that the request has originated in JavaScript code
     533  (:meth:`~django.http.HttpRequest.is_ajax` is used for this).
     535  Similarly to its HTML counterpart, it contains a collection of different
     536  pieces of information about the state of the web application.
     538  This should make it easier to read when debugging interaction with
     539  client-side Javascript code.
     541* Added the :djadminopt:`--no-location` option to the :djadmin:`makemessages`
     542  command.
     544* Changed the ``locmem`` cache backend to use
     545  ``pickle.HIGHEST_PROTOCOL`` for better compatibility with the other
     546  cache backends.
     548* Added support in the ORM for generating ``SELECT`` queries containing
     549  ``DISTINCT ON``.
     551  The ``distinct()`` ``QuerySet`` method now accepts an optional list of model
     552  field names. If specified, then the ``DISTINCT`` statement is limited to these
     553  fields. This is only supported in PostgreSQL.
     555  For more details, see the documentation for
     556  :meth:`~django.db.models.query.QuerySet.distinct`.
     558Backwards incompatible changes in 1.4
     561``BooleanField`` set to None when default value not specified
     564In previous versions of Django, a model's ``BooleanField`` would get ``False``
     565value when no default was provided. Now ``None`` value is used.
     570The included administration app ``django.contrib.admin`` has for a long time
     571shipped with a default set of static files such as JavaScript, images and
     572stylesheets. Django 1.3 added a new contrib app ``django.contrib.staticfiles``
     573to handle such files in a generic way and defined conventions for static
     574files included in apps.
     576Starting in Django 1.4 the admin's static files also follow this
     577convention to make it easier to deploy the included files. In previous
     578versions of Django, it was also common to define an ``ADMIN_MEDIA_PREFIX``
     579setting to point to the URL where the admin's static files are served by a
     580web server. This setting has now been deprecated and replaced by the more
     581general setting :setting:`STATIC_URL`. Django will now expect to find the
     582admin static files under the URL ``<STATIC_URL>/admin/``.
     584If you've previously used a URL path for ``ADMIN_MEDIA_PREFIX`` (e.g.
     585``/media/``) simply make sure :setting:`STATIC_URL` and :setting:`STATIC_ROOT`
     586are configured and your web server serves the files correctly. The development
     587server continues to serve the admin files just like before. Don't hesitate to
     588consult the :doc:`static files howto </howto/static-files>` for further
     591In case your ``ADMIN_MEDIA_PREFIX`` is set to an specific domain (e.g.
     592``http://media.example.com/admin/``) make sure to also set your
     593:setting:`STATIC_URL` setting to the correct URL, for example
     596.. warning::
     598    If you're implicitely relying on the path of the admin static files on
     599    your server's file system when you deploy your site, you have to update
     600    that path. The files were moved from :file:`django/contrib/admin/media/`
     601    to :file:`django/contrib/admin/static/admin/`.
     603Supported browsers for the admin
     606Django hasn't had a clear policy on which browsers are supported for using the
     607admin app. Django's new policy formalizes existing practices: `YUI's A-grade`_
     608browsers should provide a fully-functional admin experience, with the notable
     609exception of IE6, which is no longer supported.
     611Released over ten years ago, IE6 imposes many limitations on modern web
     612development. The practical implications of this policy are that contributors
     613are free to improve the admin without consideration for these limitations.
     615This new policy **has no impact** on development outside of the admin. Users of
     616Django are free to develop webapps compatible with any range of browsers.
     618.. _YUI's A-grade: http://yuilibrary.com/yui/docs/tutorials/gbs/
     620Removed admin icons
     623As part of an effort to improve the performance and usability of the admin's
     624changelist sorting interface and of the admin's :attr:`horizontal
     625<django.contrib.admin.ModelAdmin.filter_horizontal>` and :attr:`vertical
     626<django.contrib.admin.ModelAdmin.filter_vertical>` "filter" widgets, some icon
     627files were removed and grouped into two sprite files.
     629Specifically: ``selector-add.gif``, ``selector-addall.gif``,
     630``selector-remove.gif``, ``selector-removeall.gif``,
     631``selector_stacked-add.gif`` and ``selector_stacked-remove.gif`` were
     632combined into ``selector-icons.gif``; and ``arrow-up.gif`` and
     633``arrow-down.gif`` were combined into ``sorting-icons.gif``.
     635If you used those icons to customize the admin then you will want to replace
     636them with your own icons or retrieve them from a previous release.
     638CSS class names in admin forms
     641To avoid conflicts with other common CSS class names (e.g. "button"), a prefix
     642"field-" has been added to all CSS class names automatically generated from the
     643form field names in the main admin forms, stacked inline forms and tabular
     644inline cells. You will need to take that prefix into account in your custom
     645style sheets or javascript files if you previously used plain field names as
     646selectors for custom styles or javascript transformations.
     648Compatibility with old signed data
     651Django 1.3 changed the cryptographic signing mechanisms used in a number of
     652places in Django. While Django 1.3 kept fallbacks that would accept hashes
     653produced by the previous methods, these fallbacks are removed in Django 1.4.
     655So, if you upgrade to Django 1.4 directly from 1.2 or earlier, you may
     656lose/invalidate certain pieces of data that have been cryptographically signed
     657using an old method. To avoid this, use Django 1.3 first for a period of time
     658to allow the signed data to expire naturally. The affected parts are detailed
     659below, with 1) the consequences of ignoring this advice and 2) the amount of
     660time you need to run Django 1.3 for the data to expire or become irrelevant.
     662* ``contrib.sessions`` data integrity check
     664  * consequences: the user will be logged out, and session data will be lost.
     666  * time period: defined by :setting:`SESSION_COOKIE_AGE`.
     668* ``contrib.auth`` password reset hash
     670  * consequences: password reset links from before the upgrade will not work.
     672  * time period: defined by :setting:`PASSWORD_RESET_TIMEOUT_DAYS`.
     674Form-related hashes — these are much shorter lifetime, and are relevant only for
     675the short window where a user might fill in a form generated by the pre-upgrade
     676Django instance, and try to submit it to the upgraded Django instance:
     678* ``contrib.comments`` form security hash
     680  * consequences: the user will see a validation error "Security hash failed".
     682  * time period: the amount of time you expect users to take filling out comment
     683    forms.
     685* ``FormWizard`` security hash
     687  * consequences: the user will see an error about the form having expired,
     688    and will be sent back to the first page of the wizard, losing the data
     689    they have entered so far.
     691  * time period: the amount of time you expect users to take filling out the
     692    affected forms.
     694* CSRF check
     696  * Note: This is actually a Django 1.1 fallback, not Django 1.2,
     697    and applies only if you are upgrading from 1.1.
     699  * consequences: the user will see a 403 error with any CSRF protected POST
     700    form.
     702  * time period: the amount of time you expect user to take filling out
     703    such forms.
     708Starting in the 1.4 release the
     709:class:`~django.contrib.flatpages.middleware.FlatpageFallbackMiddleware` only
     710adds a trailing slash and redirects if the resulting URL refers to an existing
     711flatpage. For example, requesting ``/notaflatpageoravalidurl`` in a previous
     712version would redirect to ``/notaflatpageoravalidurl/``, which would
     713subsequently raise a 404. Requesting ``/notaflatpageoravalidurl`` now will
     714immediately raise a 404. Additionally redirects returned by flatpages are now
     715permanent (301 status code) to match the behavior of the
     718Serialization of :class:`~datetime.datetime` and :class:`~datetime.time`
     721As a consequence of time zone support, and according to the ECMA-262
     722specification, some changes were made to the JSON serializer:
     724- It includes the time zone for aware datetime objects. It raises an exception
     725  for aware time objects.
     726- It includes milliseconds for datetime and time objects. There is still
     727  some precision loss, because Python stores microseconds (6 digits) and JSON
     728  only supports milliseconds (3 digits). However, it's better than discarding
     729  microseconds entirely.
     731The XML serializer was also changed to use the ISO8601 format for datetimes.
     732The letter ``T`` is used to separate the date part from the time part, instead
     733of a space. Time zone information is included in the ``[+-]HH:MM`` format.
     735The serializers will dump datetimes in fixtures with these new formats. They
     736can still load fixtures that use the old format.
     738``supports_timezone`` changed to ``False`` for SQLite
     741The database feature ``supports_timezone`` used to be ``True`` for SQLite.
     742Indeed, if you saved an aware datetime object, SQLite stored a string that
     743included an UTC offset. However, this offset was ignored when loading the value
     744back from the database, which could corrupt the data.
     746In the context of time zone support, this flag was changed to ``False``, and
     747datetimes are now stored without time zone information in SQLite. When
     748:setting:`USE_TZ` is ``False``, if you attempt to save an aware datetime
     749object, Django raises an exception.
     751Database connection's thread-locality
     754``DatabaseWrapper`` objects (i.e. the connection objects referenced by
     755``django.db.connection`` and ``django.db.connections["some_alias"]``) used to
     756be thread-local. They are now global objects in order to be potentially shared
     757between multiple threads. While the individual connection objects are now
     758global, the ``django.db.connections`` dictionary referencing those objects is
     759still thread-local. Therefore if you just use the ORM or
     760``DatabaseWrapper.cursor()`` then the behavior is still the same as before.
     761Note, however, that ``django.db.connection`` does not directly reference the
     762default ``DatabaseWrapper`` object anymore and is now a proxy to access that
     763object's attributes. If you need to access the actual ``DatabaseWrapper``
     764object, use ``django.db.connections[DEFAULT_DB_ALIAS]`` instead.
     766As part of this change, all underlying SQLite connections are now enabled for
     767potential thread-sharing (by passing the ``check_same_thread=False`` attribute
     768to pysqlite). ``DatabaseWrapper`` however preserves the previous behavior by
     769disabling thread-sharing by default, so this does not affect any existing
     770code that purely relies on the ORM or on ``DatabaseWrapper.cursor()``.
     772Finally, while it is now possible to pass connections between threads, Django
     773does not make any effort to synchronize access to the underlying backend.
     774Concurrency behavior is defined by the underlying backend implementation.
     775Check their documentation for details.
     780Django's :doc:`comments app </ref/contrib/comments/index>` has historically
     781supported excluding the comments of a special user group, but we've never
     782documented the feature properly and didn't enforce the exclusion in other parts
     783of the app such as the template tags. To fix this problem, we removed the code
     784from the feed class.
     786If you rely on the feature and want to restore the old behavior, simply use
     787a custom comment model manager to exclude the user group, like this::
     789    from django.conf import settings
     790    from django.contrib.comments.managers import CommentManager
     792    class BanningCommentManager(CommentManager):
     793        def get_query_set(self):
     794            qs = super(BanningCommentManager, self).get_query_set()
     795            if getattr(settings, 'COMMENTS_BANNED_USERS_GROUP', None):
     796                where = ['user_id NOT IN (SELECT user_id FROM auth_user_groups WHERE group_id = %s)']
     797                params = [settings.COMMENTS_BANNED_USERS_GROUP]
     798                qs = qs.extra(where=where, params=params)
     799            return qs
     801Save this model manager in your custom comment app (e.g. in
     802``my_comments_app/managers.py``) and add it your
     803:ref:`custom comment app model <custom-comment-app-api>`::
     805    from django.db import models
     806    from django.contrib.comments.models import Comment
     808    from my_comments_app.managers import BanningCommentManager
     810    class CommentWithTitle(Comment):
     811        title = models.CharField(max_length=300)
     813        objects = BanningCommentManager()
     815For more details, see the documentation about
     816:doc:`customizing the comments framework </ref/contrib/comments/custom>`.
     818`IGNORABLE_404_STARTS` and `IGNORABLE_404_ENDS` settings
     821Until Django 1.3, it was possible to exclude some URLs from Django's
     822:doc:`404 error reporting</howto/error-reporting>` by adding prefixes to
     823:setting:`IGNORABLE_404_STARTS` and suffixes to :setting:`IGNORABLE_404_ENDS`.
     825In Django 1.4, these two settings are superseded by
     826:setting:`IGNORABLE_404_URLS`, which is a list of compiled regular expressions.
     827Django won't send an email for 404 errors on URLs that match any of them.
     829Furthermore, the previous settings had some rather arbitrary default values::
     831    IGNORABLE_404_STARTS = ('/cgi-bin/', '/_vti_bin', '/_vti_inf')
     832    IGNORABLE_404_ENDS = ('mail.pl', 'mailform.pl', 'mail.cgi', 'mailform.cgi',
     833                          'favicon.ico', '.php')
     835It's not Django's role to decide if your website has a legacy ``/cgi-bin/``
     836section or a ``favicon.ico``. As a consequence, the default values of
     837:setting:`IGNORABLE_404_URLS`, :setting:`IGNORABLE_404_STARTS` and
     838:setting:`IGNORABLE_404_ENDS` are all now empty.
     840If you have customized :setting:`IGNORABLE_404_STARTS` or
     841:setting:`IGNORABLE_404_ENDS`, or if you want to keep the old default value,
     842you should add the following lines in your settings file::
     844    import re
     845    IGNORABLE_404_URLS = (
     846        # for each <prefix> in IGNORABLE_404_STARTS
     847        re.compile(r'^<prefix>'),
     848        # for each <suffix> in IGNORABLE_404_ENDS
     849        re.compile(r'<suffix>$'),
     850    )
     852Don't forget to escape characters that have a special meaning in a regular
     855CSRF protection extended to PUT and DELETE
     858Previously, Django's :doc:`CSRF protection </ref/contrib/csrf/>` provided
     859protection against only POST requests. Since use of PUT and DELETE methods in
     860AJAX applications is becoming more common, we now protect all methods not
     861defined as safe by :rfc:`2616` i.e. we exempt GET, HEAD, OPTIONS and TRACE, and
     862enforce protection on everything else.
     864If you are using PUT or DELETE methods in AJAX applications, please see the
     865:ref:`instructions about using AJAX and CSRF <csrf-ajax>`.
     870This was an alias to ``django.template.loader`` since 2005, it has been removed
     871without emitting a warning due to the length of the deprecation. If your code
     872still referenced this please use ``django.template.loader`` instead.
     877This functionality has been removed due to intractable performance and
     878security issues. Any existing usage of ``verify_exists`` should be
     884The ``open`` method of the base Storage class took an obscure parameter
     885``mixin`` which allowed you to dynamically change the base classes of the
     886returned file object. This has been removed. In the rare case you relied on the
     887`mixin` parameter, you can easily achieve the same by overriding the `open`
     888method, e.g.::
     890    from django.core.files import File
     891    from django.core.files.storage import FileSystemStorage
     893    class Spam(File):
     894        """
     895        Spam, spam, spam, spam and spam.
     896        """
     897        def ham(self):
     898            return 'eggs'
     900    class SpamStorage(FileSystemStorage):
     901        """
     902        A custom file storage backend.
     903        """
     904        def open(self, name, mode='rb'):
     905            return Spam(open(self.path(name), mode))
     907YAML deserializer now uses ``yaml.safe_load``
     910``yaml.load`` is able to construct any Python object, which may trigger
     911arbitrary code execution if you process a YAML document that comes from an
     912untrusted source. This feature isn't necessary for Django's YAML deserializer,
     913whose primary use is to load fixtures consisting of simple objects. Even though
     914fixtures are trusted data, for additional security, the YAML deserializer now
     915uses ``yaml.safe_load``.
     917Features deprecated in 1.4
     920Old styles of calling ``cache_page`` decorator
     923Some legacy ways of calling :func:`~django.views.decorators.cache.cache_page`
     924have been deprecated, please see the docs for the correct way to use this
     927Support for PostgreSQL versions older than 8.2
     930Django 1.3 dropped support for PostgreSQL versions older than 8.0 and the
     931relevant documents suggested to use a recent version because of performance
     932reasons but more importantly because end of the upstream support periods for
     933releases 8.0 and 8.1 was near (November 2010).
     935Django 1.4 takes that policy further and sets 8.2 as the minimum PostgreSQL
     936version it officially supports.
     938Request exceptions are now always logged
     941When :doc:`logging support </topics/logging/>` was added to Django in 1.3, the
     942admin error email support was moved into the
     943:class:`django.utils.log.AdminEmailHandler`, attached to the
     944``'django.request'`` logger. In order to maintain the established behavior of
     945error emails, the ``'django.request'`` logger was called only when
     946:setting:`DEBUG` was ``False``.
     948To increase the flexibility of error logging for requests, the
     949``'django.request'`` logger is now called regardless of the value of
     950:setting:`DEBUG`, and the default settings file for new projects now includes a
     951separate filter attached to :class:`django.utils.log.AdminEmailHandler` to
     952prevent admin error emails in ``DEBUG`` mode::
     954   'filters': {
     955        'require_debug_false': {
     956            '()': 'django.utils.log.RequireDebugFalse'
     957        }
     958    },
     959    'handlers': {
     960        'mail_admins': {
     961            'level': 'ERROR',
     962            'filters': ['require_debug_false'],
     963            'class': 'django.utils.log.AdminEmailHandler'
     964        }
     965    },
     967If your project was created prior to this change, your :setting:`LOGGING`
     968setting will not include this new filter. In order to maintain
     969backwards-compatibility, Django will detect that your ``'mail_admins'`` handler
     970configuration includes no ``'filters'`` section, and will automatically add
     971this filter for you and issue a pending-deprecation warning. This will become a
     972deprecation warning in Django 1.5, and in Django 1.6 the
     973backwards-compatibility shim will be removed entirely.
     975The existence of any ``'filters'`` key under the ``'mail_admins'`` handler will
     976disable this backward-compatibility shim and deprecation warning.
     981Until Django 1.3 the functions :func:`~django.conf.urls.include`,
     982:func:`~django.conf.urls.patterns` and :func:`~django.conf.urls.url` plus
     983:data:`~django.conf.urls.handler404`, :data:`~django.conf.urls.handler500`
     984were located in a ``django.conf.urls.defaults`` module.
     986Starting with Django 1.4 they are now available in :mod:`django.conf.urls`.
     991Databrowse has not seen active development for some time, and this does not show
     992any sign of changing. There had been a suggestion for a `GSOC project`_ to
     993integrate the functionality of databrowse into the admin, but no progress was
     994made. While Databrowse has been deprecated, an enhancement of
     995``django.contrib.admin`` providing a similar feature set is still possible.
     997.. _GSOC project: https://code.djangoproject.com/wiki/SummerOfCode2011#Integratedatabrowseintotheadmin
     999The code that powers Databrowse is licensed under the same terms as Django
     1000itself, and so is available to be adopted by an individual or group as
     1001a third-party project.
     1006This function temporarily modified ``sys.path`` in order to make the parent
     1007"project" directory importable under the old flat :djadmin:`startproject`
     1008layout. This function is now deprecated, as its path workarounds are no longer
     1009needed with the new ``manage.py`` and default project layout.
     1011This function was never documented or part of the public API, but was widely
     1012recommended for use in setting up a "Django environment" for a user script.
     1013These uses should be replaced by setting the ``DJANGO_SETTINGS_MODULE``
     1014environment variable or using :func:`django.conf.settings.configure`.
     1019This function was previously used by ``manage.py`` to execute a management
     1020command. It is identical to
     1021``django.core.management.execute_from_command_line``, except that it first
     1022calls ``setup_environ``, which is now deprecated. As such, ``execute_manager``
     1023is also deprecated; ``execute_from_command_line`` can be used instead. Neither
     1024of these functions is documented as part of the public API, but a deprecation
     1025path is needed due to use in existing ``manage.py`` files.
     1027``is_safe`` and ``needs_autoescape`` attributes of template filters
     1030Two flags, ``is_safe`` and ``needs_autoescape``, define how each template filter
     1031interacts with Django's auto-escaping behavior. They used to be attributes of
     1032the filter function::
     1034    @register.filter
     1035    def noop(value):
     1036        return value
     1037    noop.is_safe = True
     1039However, this technique caused some problems in combination with decorators,
     1040especially :func:`@stringfilter <django.template.defaultfilters.stringfilter>`.
     1041Now, the flags are keyword arguments of :meth:`@register.filter
     1044    @register.filter(is_safe=True)
     1045    def noop(value):
     1046        return value
     1048See :ref:`filters and auto-escaping <filters-auto-escaping>` for more information.
     1050Session cookies now have the ``httponly`` flag by default
     1053Session cookies now include the ``httponly`` attribute by default to
     1054help reduce the impact of potential XSS attacks. For strict backwards
     1055compatibility, use ``SESSION_COOKIE_HTTPONLY = False`` in your settings file.
     1057Wildcard expansion of application names in `INSTALLED_APPS`
     1060Until Django 1.3, :setting:`INSTALLED_APPS` accepted wildcards in application
     1061names, like ``django.contrib.*``. The expansion was performed by a
     1062filesystem-based implementation of ``from <package> import *``. Unfortunately,
     1063`this can't be done reliably`_.
     1065This behavior was never documented. Since it is un-pythonic and not obviously
     1066useful, it was removed in Django 1.4. If you relied on it, you must edit your
     1067settings file to list all your applications explicitly.
     1069.. _this can't be done reliably: http://docs.python.org/tutorial/modules.html#importing-from-a-package
     1071``HttpRequest.raw_post_data`` renamed to ``HttpRequest.body``
     1074This attribute was confusingly named ``HttpRequest.raw_post_data``, but it
     1075actually provided the body of the HTTP request. It's been renamed to
     1076``HttpRequest.body``, and ``HttpRequest.raw_post_data`` has been deprecated.
     1079The Django 1.4 roadmap
     1082Before the final Django 1.4 release, several other preview/development releases
     1083will be made available. The current schedule consists of at least the following:
     1085* Week of **January 30, 2012**: First Django 1.4 beta release; final
     1086  feature freeze for Django 1.4.
     1088* Week of **February 27, 2012**: First Django 1.4 release
     1089  candidate; string freeze for translations.
     1091* Week of **March 5, 2012**: Django 1.4 final release.
     1093If necessary, additional alpha, beta or release-candidate packages
     1094will be issued prior to the final 1.4 release. Django 1.4 will be
     1095released approximately one week after the final release candidate.
     1097What you can do to help
     1100In order to provide a high-quality 1.4 release, we need your help. Although this
     1101beta release is, again, *not* intended for production use, you can help the
     1102Django team by trying out the beta codebase in a safe test environment and
     1103reporting any bugs or issues you encounter. The Django ticket tracker is the
     1104central place to search for open issues:
     1106* http://code.djangoproject.com/timeline
     1108Please open new tickets if no existing ticket corresponds to a problem you're
     1109running into.
     1111Additionally, discussion of Django development, including progress toward the
     11121.3 release, takes place daily on the django-developers mailing list:
     1114* http://groups.google.com/group/django-developers
     1116... and in the ``#django-dev`` IRC channel on ``irc.freenode.net``. If you're
     1117interested in helping out with Django's development, feel free to join the
     1118discussions there.
     1120Django's online documentation also includes pointers on how to contribute to
     1123* :doc:`How to contribute to Django </internals/contributing/index>`
     1125Contributions on any level -- developing code, writing documentation or simply
     1126triaging tickets and helping to test proposed bugfixes -- are always welcome and
     1129Several development sprints will also be taking place before the 1.4
     1130release; these will typically be announced in advance on the
     1131django-developers mailing list, and anyone who wants to help is
     1132welcome to join in.
  • tests/regressiontests/model_inheritance_regress/tests.py

    180180        """
    181181        Regression test for #6755
    182182        """
    183         r = Restaurant(serves_pizza=False)
     183        r = Restaurant(serves_pizza=False, serves_hot_dogs=False)
    184184        r.save()
    185185        self.assertEqual(r.id, r.place_ptr_id)
    186186        orig_id = r.id
    187         r = Restaurant(place_ptr_id=orig_id, serves_pizza=True)
     187        r = Restaurant(place_ptr_id=orig_id, serves_pizza=True, serves_hot_dogs=False)
    188188        r.save()
    189189        self.assertEqual(r.id, orig_id)
    190190        self.assertEqual(r.id, r.place_ptr_id)
  • tests/regressiontests/model_fields/tests.py

    211211            select={'string_length': 'LENGTH(string)'})[0]
    212212        self.assertFalse(isinstance(b5.pk, bool))
     214    def test_null_default(self):
     215        # http://code.djangoproject.com/ticket/15124
     216        from django.db import IntegrityError
     217        b = BooleanModel()
     218        self.assertEqual(b.bfield, None)
     219        self.assertRaises(IntegrityError, b.save)
    214221class ChoicesTests(test.TestCase):
    215222    def test_choices_and_field_display(self):
    216223        """
  • django/db/models/fields/__init__.py

    553553    description = _("Boolean (Either True or False)")
    554554    def __init__(self, *args, **kwargs):
    555555        kwargs['blank'] = True
    556         if 'default' not in kwargs and not kwargs.get('null'):
    557             kwargs['default'] = False
    558556        Field.__init__(self, *args, **kwargs)
    560558    def get_internal_type(self):
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