Django 1.2 release notes¶
May 17, 2010.
Welcome to Django 1.2!
Nearly a year in the making, Django 1.2 packs an impressive list of new features and lots of bug fixes. These release notes cover the new features, as well as important changes you’ll want to be aware of when upgrading from Django 1.1 or older versions.
Overview¶
Django 1.2 introduces several large, important new features, including:
- Support for multiple database connections in a single Django instance.
- Model validation inspired by Django’s form validation.
- Vastly improved protection against Cross-Site Request Forgery (CSRF).
- A new user “messages” framework with support for cookie- and session-based message for both anonymous and authenticated users.
- Hooks for object-level permissions, permissions for anonymous users, and more flexible username requirements.
- Customization of email sending via email backends.
- New “smart” if template tag which supports comparison operators.
These are just the highlights; full details and a complete list of features may be found below.
See also
Django Advent covered the release of Django 1.2 with a series of articles and tutorials that cover some of the new features in depth.
Wherever possible these features have been introduced in a backwards-compatible manner per our API stability policy policy.
However, a handful of features have changed in ways that, for some users, will be backwards-incompatible. The big changes are:
Support for Python 2.3 has been dropped. See the full notes below.
The new CSRF protection framework is not backwards-compatible with the old system. Users of the old system will not be affected until the old system is removed in Django 1.4.
However, upgrading to the new CSRF protection framework requires a few important backwards-incompatible changes, detailed in CSRF Protection, below.
Authors of custom
Field
subclasses should be aware that a number of methods have had a change in prototype, detailed under get_db_prep_*() methods on Field, below.The internals of template tags have changed somewhat; authors of custom template tags that need to store state (e.g. custom control flow tags) should ensure that their code follows the new rules for stateful template tags
The
user_passes_test()
,login_required()
, andpermission_required()
, decorators fromdjango.contrib.auth
only apply to functions and no longer work on methods. There’s a simple one-line fix detailed below.
Again, these are just the big features that will affect the most users. Users upgrading from previous versions of Django are heavily encouraged to consult the complete list of backwards-incompatible changes and the list of deprecated features.
Python compatibility¶
While not a new feature, it’s important to note that Django 1.2 introduces the first shift in our Python compatibility policy since Django’s initial public debut. Previous Django releases were tested and supported on 2.x Python versions from 2.3 up; Django 1.2, however, drops official support for Python 2.3. As such, the minimum Python version required for Django is now 2.4, and Django is tested and supported on Python 2.4, 2.5 and 2.6, and will be supported on the as-yet-unreleased Python 2.7.
This change should affect only a small number of Django users, as most operating-system vendors today are shipping Python 2.4 or newer as their default version. If you’re still using Python 2.3, however, you’ll need to stick to Django 1.1 until you can upgrade; per our support policy, Django 1.1 will continue to receive security support until the release of Django 1.3.
A roadmap for Django’s overall 2.x Python support, and eventual transition to Python 3.x, is currently being developed, and will be announced prior to the release of Django 1.3.
What’s new in Django 1.2¶
Support for multiple databases¶
Django 1.2 adds the ability to use more than one database in your Django project. Queries can be issued at a
specific database with the using()
method on QuerySet
objects.
Individual objects can be saved to a specific database by providing a using
argument when you call save()
.
Model validation¶
Model instances now have support for validating their own data, and both model and form fields now accept configurable
lists of validators specifying reusable, encapsulated
validation behavior. Note, however, that validation must still be performed
explicitly. Simply invoking a model instance’s save()
method will not
perform any validation of the instance’s data.
Improved CSRF protection¶
Django now has much improved protection against Cross-Site Request Forgery (CSRF) attacks. This type of attack occurs when a malicious website contains a link, a form button or some JavaScript that is intended to perform some action on your website, using the credentials of a logged-in user who visits the malicious site in their browser. A related type of attack, “login CSRF,” where an attacking site tricks a user’s browser into logging into a site with someone else’s credentials, is also covered.
Messages framework¶
Django now includes a robust and configurable messages framework with built-in support for cookie- and session-based messaging, for both anonymous and authenticated clients. The messages framework replaces the deprecated user message API and allows you to temporarily store messages in one request and retrieve them for display in a subsequent request (usually the next one).
Object-level permissions¶
A foundation for specifying permissions at the per-object level has been added.
Although there is no implementation of this in core, a custom authentication
backend can provide this implementation and it will be used by
django.contrib.auth.models.User
. See the authentication docs for more information.
Permissions for anonymous users¶
If you provide a custom auth backend with supports_anonymous_user
set to
True
, AnonymousUser will check the backend for permissions, just like
User already did. This is useful for centralizing permission handling - apps
can always delegate the question of whether something is allowed or not to
the authorization/authentication backend. See the authentication
docs for more details.
Relaxed requirements for usernames¶
The built-in User
model’s
username
field now allows a wider range
of characters, including @
, +
, .
and -
characters.
Email backends¶
You can now configure the way that Django sends email. Instead of using SMTP to send all email, you can now choose a configurable email backend to send messages. If your hosting provider uses a sandbox or some other non-SMTP technique for sending mail, you can now construct an email backend that will allow Django’s standard mail sending methods to use those facilities.
This also makes it easier to debug mail sending. Django ships with backend implementations that allow you to send email to a file, to the console, or to memory. You can even configure all email to be thrown away.
“Smart” if
tag¶
The if
tag has been upgraded to be much more powerful. First, we’ve
added support for comparison operators. No longer will you have to type:
{% ifnotequal a b %}
...
{% endifnotequal %}
You can now do this:
{% if a != b %}
...
{% endif %}
There’s really no reason to use {% ifequal %}
or {% ifnotequal %}
anymore, unless you’re the nostalgic type.
The operators supported are ==
, !=
, <
, >
, <=
, >=
,
in
and not in
, all of which work like the Python operators, in addition
to and
, or
and not
, which were already supported.
Also, filters may now be used in the if
expression. For example:
<div
{% if user.email|lower == message.recipient|lower %}
class="highlight"
{% endif %}
>{{ message }}</div>
Template caching¶
In previous versions of Django, every time you rendered a template, it
would be reloaded from disk. In Django 1.2, you can use a cached
template loader to load templates once, then
cache the result for every subsequent render. This can lead to a
significant performance improvement if your templates are broken into
lots of smaller subtemplates (using the {% extends %}
or {%
include %}
tags).
As a side effect, it is now much easier to support non-Django template languages.
Class-based template loaders¶
As part of the changes made to introduce Template caching and following a general trend in Django, the template loaders API has been modified to use template loading mechanisms that are encapsulated in Python classes as opposed to functions, the only method available until Django 1.1.
All the template loaders shipped with Django have
been ported to the new API but they still implement the function-based API and
the template core machinery still accepts function-based loaders (builtin or
third party) so there is no immediate need to modify your TEMPLATE_LOADERS
setting in existing projects, things will keep working if you leave it
untouched up to and including the Django 1.3 release.
If you have developed your own custom template loaders we suggest to consider porting them to a class-based implementation because the code for backwards compatibility with function-based loaders starts its deprecation process in Django 1.2 and will be removed in Django 1.4. There is a description of the API these loader classes must implement in the template API reference and you can also examine the source code of the loaders shipped with Django.
Natural keys in fixtures¶
Fixtures can now refer to remote objects using Natural keys. This lookup scheme is an alternative to the normal primary-key based object references in a fixture, improving readability and resolving problems referring to objects whose primary key value may not be predictable or known.
Fast failure for tests¶
Both the test
subcommand of django-admin.py
and the
runtests.py
script used to run Django’s own test suite now support a
--failfast
option. When specified, this option causes the test runner to
exit after encountering a failure instead of continuing with the test run. In
addition, the handling of Ctrl-C
during a test run has been improved to
trigger a graceful exit from the test run that reports details of the tests that
were run before the interruption.
BigIntegerField
¶
Models can now use a 64-bit BigIntegerField
type.
Improved localization¶
Django’s internationalization framework has been expanded with locale-aware formatting and form processing. That means, if enabled, dates and numbers on templates will be displayed using the format specified for the current locale. Django will also use localized formats when parsing data in forms. See Format localization for more details.
readonly_fields
in ModelAdmin
¶
django.contrib.admin.ModelAdmin.readonly_fields
has been added to
enable non-editable fields in add/change pages for models and inlines. Field
and calculated values can be displayed alongside editable fields.
Customizable syntax highlighting¶
You can now use a DJANGO_COLORS
environment variable to modify or
disable the colors used by django-admin.py
to provide syntax
highlighting.
Syndication feeds as views¶
Syndication feeds can now be used directly as
views in your URLconf. This means that you can
maintain complete control over the URL structure of your feeds. Like any other
view, feeds views are passed a request
object, so you can do anything you
would normally do with a view, like user based access control, or making a feed
a named URL.
GeoDjango¶
The most significant new feature for GeoDjango in 1.2 is support for multiple spatial databases. As a result, the following spatial database backends are now included:
django.contrib.gis.db.backends.postgis
django.contrib.gis.db.backends.mysql
django.contrib.gis.db.backends.oracle
django.contrib.gis.db.backends.spatialite
GeoDjango now supports the rich capabilities added in the PostGIS 1.5 release. New features include support for the geography type and enabling of distance queries with non-point geometries on geographic coordinate systems.
Support for 3D geometry fields was added, and may be enabled
by setting the dim
keyword to 3 in your GeometryField
.
The Extent3D
aggregate
and extent3d()
GeoQuerySet
method were added as a part of this feature.
The force_rhr()
, reverse_geom()
, and geohash()
GeoQuerySet
methods are new.
The GEOS interface was updated to use thread-safe C library functions when available on the platform.
The GDAL interface now allows the user to set a
spatial_filter
on the features returned
when iterating over a Layer
.
Finally, GeoDjango’s documentation is now
included with Django’s and is no longer hosted separately at geodjango.org
.
New now
template tag format specifier characters: c
and u
¶
The argument to the now
has gained two new format characters:
c
to specify that a datetime value should be formatted in ISO 8601
format, and u
that allows output of the microseconds part of a
datetime or time value.
These are also available in others parts like the date
and
time
template filters, the humanize
template tag library
and the new format localization framework.
Backwards-incompatible changes in 1.2¶
Wherever possible the new features above have been introduced in a backwards-compatible manner per our API stability policy policy. This means that practically all existing code which worked with Django 1.1 will continue to work with Django 1.2; such code will, however, begin issuing warnings (see below for details).
However, a handful of features have changed in ways that, for some users, will be immediately backwards-incompatible. Those changes are detailed below.
CSRF Protection¶
We’ve made large changes to the way CSRF protection works, detailed in the CSRF documentation. Here are the major changes you should be aware of:
CsrfResponseMiddleware
andCsrfMiddleware
have been deprecated and will be removed completely in Django 1.4, in favor of a template tag that should be inserted into forms.All contrib apps use a
csrf_protect
decorator to protect the view. This requires the use of thecsrf_token
template tag in the template. If you have used custom templates for contrib views, you MUST READ THE UPGRADE INSTRUCTIONS to fix those templates.Documentation removed
The upgrade notes have been removed in current Django docs. Please refer to the docs for Django 1.3 or older to find these instructions.
CsrfViewMiddleware
is included inMIDDLEWARE_CLASSES
by default. This turns on CSRF protection by default, so views that accept POST requests need to be written to work with the middleware. Instructions on how to do this are found in the CSRF docs.All of the CSRF has moved from contrib to core (with backwards compatible imports in the old locations, which are deprecated and will cease to be supported in Django 1.4).
get_db_prep_*()
methods on Field
¶
Prior to Django 1.2, a custom Field
had the option of defining
several functions to support conversion of Python values into
database-compatible values. A custom field might look something like:
class CustomModelField(models.Field):
# ...
def db_type(self):
# ...
def get_db_prep_save(self, value):
# ...
def get_db_prep_value(self, value):
# ...
def get_db_prep_lookup(self, lookup_type, value):
# ...
In 1.2, these three methods have undergone a change in prototype, and two extra methods have been introduced:
class CustomModelField(models.Field):
# ...
def db_type(self, connection):
# ...
def get_prep_value(self, value):
# ...
def get_prep_lookup(self, lookup_type, value):
# ...
def get_db_prep_save(self, value, connection):
# ...
def get_db_prep_value(self, value, connection, prepared=False):
# ...
def get_db_prep_lookup(self, lookup_type, value, connection, prepared=False):
# ...
These changes are required to support multiple databases –
db_type
and get_db_prep_*
can no longer make any assumptions
regarding the database for which it is preparing. The connection
argument now provides the preparation methods with the specific
connection for which the value is being prepared.
The two new methods exist to differentiate general data-preparation
requirements from requirements that are database-specific. The
prepared
argument is used to indicate to the database-preparation
methods whether generic value preparation has been performed. If
an unprepared (i.e., prepared=False
) value is provided to the
get_db_prep_*()
calls, they should invoke the corresponding
get_prep_*()
calls to perform generic data preparation.
We’ve provided conversion functions that will transparently
convert functions adhering to the old prototype into functions
compatible with the new prototype. However, these conversion functions
will be removed in Django 1.4, so you should upgrade your Field
definitions to use the new prototype as soon as possible.
If your get_db_prep_*()
methods made no use of the database
connection, you should be able to upgrade by renaming
get_db_prep_value()
to get_prep_value()
and
get_db_prep_lookup()
to get_prep_lookup()
. If you require
database specific conversions, then you will need to provide an
implementation get_db_prep_*
that uses the connection
argument to resolve database-specific values.
Stateful template tags¶
Template tags that store rendering state on their Node
subclass
have always been vulnerable to thread-safety and other issues; as of
Django 1.2, however, they may also cause problems when used with the
new cached template loader.
All of the built-in Django template tags are safe to use with the cached
loader, but if you’re using custom template tags that come from third
party packages, or from your own code, you should ensure that the
Node
implementation for each tag is thread-safe. For more
information, see
template tag thread safety considerations.
You may also need to update your templates if you were relying on the
implementation of Django’s template tags not being thread safe. The
cycle
tag is the most likely to be affected in this way,
especially when used in conjunction with the include
tag.
Consider the following template fragment:
{% for object in object_list %}
{% include "subtemplate.html" %}
{% endfor %}
with a subtemplate.html
that reads:
{% cycle 'even' 'odd' %}
Using the non-thread-safe, pre-Django 1.2 renderer, this would output:
even odd even odd ...
Using the thread-safe Django 1.2 renderer, you will instead get:
even even even even ...
This is because each rendering of the include
tag is an
independent rendering. When the cycle
tag was not thread safe,
the state of the cycle
tag would leak between multiple
renderings of the same include
. Now that the cycle
tag
is thread safe, this leakage no longer occurs.
user_passes_test
, login_required
and permission_required
¶
django.contrib.auth.decorators
provides the decorators
login_required
, permission_required
and
user_passes_test
. Previously it was possible to use these
decorators both on functions (where the first argument is ‘request’)
and on methods (where the first argument is ‘self’, and the second
argument is ‘request’). Unfortunately, flaws were discovered in the
code supporting this: it only works in limited circumstances, and
produces errors that are very difficult to debug when it does not
work.
For this reason, the ‘auto adapt’ behavior has been removed, and if
you are using these decorators on methods, you will need to manually
apply django.utils.decorators.method_decorator()
to convert the
decorator to one that works with methods. For example, you would
change code from this:
class MyClass(object):
@login_required
def my_view(self, request):
pass
to this:
from django.utils.decorators import method_decorator
class MyClass(object):
@method_decorator(login_required)
def my_view(self, request):
pass
or:
from django.utils.decorators import method_decorator
login_required_m = method_decorator(login_required)
class MyClass(object):
@login_required_m
def my_view(self, request):
pass
For those of you who’ve been following the development trunk, this
change also applies to other decorators introduced since 1.1,
including csrf_protect
, cache_control
and anything created
using decorator_from_middleware
.
if
tag changes¶
Due to new features in the if
template tag, it no longer
accepts ‘and’, ‘or’ and ‘not’ as valid variable names. Previously,
these strings could be used as variable names. Now, the keyword status
is always enforced, and template code such as {% if not %}
or {%
if and %}
will throw a TemplateSyntaxError
. Also, in
is a
new keyword and so is not a valid variable name in this tag.
LazyObject
¶
LazyObject
is an undocumented-but-often-used utility class used for lazily
wrapping other objects of unknown type.
In Django 1.1 and earlier, it handled introspection in a non-standard way,
depending on wrapped objects implementing a public method named
get_all_members()
. Since this could easily lead to name clashes, it has been
changed to use the standard Python introspection method, involving
__members__
and __dir__()
.
If you used LazyObject
in your own code
and implemented the get_all_members()
method for wrapped objects, you’ll need
to make a couple of changes:
First, if your class does not have special requirements for introspection (i.e.,
you have not implemented __getattr__()
or other methods that allow for
attributes not discoverable by normal mechanisms), you can simply remove the
get_all_members()
method. The default implementation on LazyObject
will
do the right thing.
If you have more complex requirements for introspection, first rename the
get_all_members()
method to __dir__()
. This is the standard
introspection method for Python 2.6 and above. If you require support for Python
versions earlier than 2.6, add the following code to the class:
__members__ = property(lambda self: self.__dir__())
__dict__
on model instances¶
Historically, the __dict__
attribute of a model instance has only contained
attributes corresponding to the fields on a model.
In order to support multiple database configurations, Django 1.2 has
added a _state
attribute to object instances. This attribute will
appear in __dict__
for a model instance. If your code relies on
iterating over __dict__
to obtain a list of fields, you must now
be prepared to handle or filter out the _state
attribute.
Test runner exit status code¶
The exit status code of the test runners (tests/runtests.py
and python
manage.py test
) no longer represents the number of failed tests, because a
failure of 256 or more tests resulted in a wrong exit status code. The exit
status code for the test runner is now 0 for success (no failing tests) and 1
for any number of test failures. If needed, the number of test failures can be
found at the end of the test runner’s output.
Cookie encoding¶
To fix bugs with cookies in Internet Explorer, Safari, and possibly
other browsers, our encoding of cookie values was changed so that the
comma and semicolon are treated as non-safe characters, and are
therefore encoded as \054
and \073
respectively. This could
produce backwards incompatibilities, especially if you are storing
comma or semi-colon in cookies and have JavaScript code that parses
and manipulates cookie values client-side.
ModelForm.is_valid()
and ModelForm.errors
¶
Much of the validation work for ModelForms has been moved down to the model
level. As a result, the first time you call ModelForm.is_valid()
, access
ModelForm.errors
or otherwise trigger form validation, your model will be
cleaned in-place. This conversion used to happen when the model was saved. If
you need an unmodified instance of your model, you should pass a copy to the
ModelForm
constructor.
BooleanField
on MySQL¶
In previous versions of Django, a model’s BooleanField
under MySQL
would return its value as either 1
or 0
, instead of True
or False
; for most people this wasn’t a problem because bool
is a subclass of int
in Python. In Django 1.2, however,
BooleanField
on MySQL correctly returns a real bool
. The only
time this should ever be an issue is if you were expecting the
repr
of a BooleanField
to print 1
or 0
.
Changes to the interpretation of max_num
in FormSets¶
As part of enhancements made to the handling of FormSets, the default
value and interpretation of the max_num
parameter to the
django.forms.formsets.formset_factory() and
django.forms.models.modelformset_factory() functions has changed slightly. This
change also affects the way the
max_num
argument is used for
inline admin objects.
Previously, the default value for max_num
was 0
(zero).
FormSets then used the boolean value of max_num
to determine if a
limit was to be imposed on the number of generated forms. The default
value of 0
meant that there was no default limit on the number of
forms in a FormSet.
Starting with 1.2, the default value for max_num
has been changed
to None
, and FormSets will differentiate between a value of
None
and a value of 0
. A value of None
indicates that no
limit on the number of forms is to be imposed; a value of 0
indicates that a maximum of 0 forms should be imposed. This doesn’t
necessarily mean that no forms will be displayed – see the
ModelFormSet documentation for more
details.
If you were manually specifying a value of 0
for max_num
, you
will need to update your FormSet and/or admin definitions.
email_re
¶
An undocumented regular expression for validating email addresses has been moved
from django.form.fields
to django.core.validators
. You will need to
update your imports if you are using it.
Features deprecated in 1.2¶
Finally, Django 1.2 deprecates some features from earlier releases. These features are still supported, but will be gradually phased out over the next few release cycles.
Code taking advantage of any of the features below will raise a
PendingDeprecationWarning
in Django 1.2. This warning will be
silent by default, but may be turned on using Python’s warnings
module, or by running Python with a -Wd
or -Wall
flag.
In Django 1.3, these warnings will become a DeprecationWarning
,
which is not silent. In Django 1.4 support for these features will
be removed entirely.
See also
For more details, see the documentation Django’s release process and our deprecation timeline.`
Specifying databases¶
Prior to Django 1.2, Django used a number of settings to control access to a single database. Django 1.2 introduces support for multiple databases, and as a result the way you define database settings has changed.
Any existing Django settings file will continue to work as expected until Django 1.4. Until then, old-style database settings will be automatically translated to the new-style format.
In the old-style (pre 1.2) format, you had a number of DATABASE_
settings in your settings file. For example:
DATABASE_NAME = 'test_db'
DATABASE_ENGINE = 'postgresql_psycopg2'
DATABASE_USER = 'myusername'
DATABASE_PASSWORD = 's3krit'
These settings are now in a dictionary named
DATABASES
. Each item in the dictionary corresponds to a
single database connection, with the name 'default'
describing the
default database connection. The setting names have also been
shortened. The previous sample settings would now look like this:
DATABASES = {
'default': {
'NAME': 'test_db',
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'USER': 'myusername',
'PASSWORD': 's3krit',
}
}
This affects the following settings:
Old setting | New Setting |
---|---|
DATABASE_ENGINE |
ENGINE |
DATABASE_HOST |
HOST |
DATABASE_NAME |
NAME |
DATABASE_OPTIONS |
OPTIONS |
DATABASE_PASSWORD |
PASSWORD |
DATABASE_PORT |
PORT |
DATABASE_USER |
USER |
TEST_DATABASE_CHARSET |
TEST_CHARSET |
TEST_DATABASE_COLLATION |
TEST_COLLATION |
TEST_DATABASE_NAME |
TEST_NAME |
These changes are also required if you have manually created a database
connection using DatabaseWrapper()
from your database backend of choice.
In addition to the change in structure, Django 1.2 removes the special
handling for the built-in database backends. All database backends
must now be specified by a fully qualified module name (i.e.,
django.db.backends.postgresql_psycopg2
, rather than just
postgresql_psycopg2
).
postgresql
database backend¶
The psycopg1
library has not been updated since October 2005. As a
result, the postgresql
database backend, which uses this library,
has been deprecated.
If you are currently using the postgresql
backend, you should
migrate to using the postgresql_psycopg2
backend. To update your
code, install the psycopg2
library and change the
ENGINE
setting to use
django.db.backends.postgresql_psycopg2
.
CSRF response-rewriting middleware¶
CsrfResponseMiddleware
, the middleware that automatically inserted
CSRF tokens into POST
forms in outgoing pages, has been deprecated
in favor of a template tag method (see above), and will be removed
completely in Django 1.4. CsrfMiddleware
, which includes the
functionality of CsrfResponseMiddleware
and
CsrfViewMiddleware
, has likewise been deprecated.
Also, the CSRF module has moved from contrib to core, and the old imports are deprecated, as described in the upgrading notes.
Documentation removed
The upgrade notes have been removed in current Django docs. Please refer to the docs for Django 1.3 or older to find these instructions.
SMTPConnection
¶
The SMTPConnection
class has been deprecated in favor of a generic
email backend API. Old code that explicitly instantiated an instance
of an SMTPConnection:
from django.core.mail import SMTPConnection
connection = SMTPConnection()
messages = get_notification_email()
connection.send_messages(messages)
…should now call get_connection()
to
instantiate a generic email connection:
from django.core.mail import get_connection
connection = get_connection()
messages = get_notification_email()
connection.send_messages(messages)
Depending on the value of the EMAIL_BACKEND
setting, this
may not return an SMTP connection. If you explicitly require an SMTP
connection with which to send email, you can explicitly request an
SMTP connection:
from django.core.mail import get_connection
connection = get_connection('django.core.mail.backends.smtp.EmailBackend')
messages = get_notification_email()
connection.send_messages(messages)
If your call to construct an instance of SMTPConnection
required
additional arguments, those arguments can be passed to the
get_connection()
call:
connection = get_connection('django.core.mail.backends.smtp.EmailBackend', hostname='localhost', port=1234)
User Messages API¶
The API for storing messages in the user Message
model (via
user.message_set.create
) is now deprecated and will be removed in Django
1.4 according to the standard release process.
To upgrade your code, you need to replace any instances of this:
user.message_set.create('a message')
…with the following:
from django.contrib import messages
messages.add_message(request, messages.INFO, 'a message')
Additionally, if you make use of the method, you need to replace the following:
for message in user.get_and_delete_messages():
...
…with:
from django.contrib import messages
for message in messages.get_messages(request):
...
For more information, see the full messages documentation. You should begin to update your code to use the new API immediately.
Date format helper functions¶
django.utils.translation.get_date_formats()
and
django.utils.translation.get_partial_date_formats()
have been deprecated
in favor of the appropriate calls to django.utils.formats.get_format()
,
which is locale-aware when USE_L10N
is set to True
, and falls
back to default settings if set to False
.
To get the different date formats, instead of writing this:
from django.utils.translation import get_date_formats
date_format, datetime_format, time_format = get_date_formats()
…use:
from django.utils import formats
date_format = formats.get_format('DATE_FORMAT')
datetime_format = formats.get_format('DATETIME_FORMAT')
time_format = formats.get_format('TIME_FORMAT')
Or, when directly formatting a date value:
from django.utils import formats
value_formatted = formats.date_format(value, 'DATETIME_FORMAT')
The same applies to the globals found in django.forms.fields
:
DEFAULT_DATE_INPUT_FORMATS
DEFAULT_TIME_INPUT_FORMATS
DEFAULT_DATETIME_INPUT_FORMATS
Use django.utils.formats.get_format()
to get the appropriate formats.
Function-based test runners¶
Django 1.2 changes the test runner tools to use a class-based approach. Old style function-based test runners will still work, but should be updated to use the new class-based runners.
Feed
in django.contrib.syndication.feeds
¶
The django.contrib.syndication.feeds.Feed
class has been
replaced by the django.contrib.syndication.views.Feed
class.
The old feeds.Feed
class is deprecated, and will be removed in
Django 1.4.
The new class has an almost identical API, but allows instances to be used as views. For example, consider the use of the old framework in the following URLconf:
from django.conf.urls.defaults import *
from myproject.feeds import LatestEntries, LatestEntriesByCategory
feeds = {
'latest': LatestEntries,
'categories': LatestEntriesByCategory,
}
urlpatterns = patterns('',
# ...
(r'^feeds/(?P<url>.*)/$', 'django.contrib.syndication.views.feed',
{'feed_dict': feeds}),
# ...
)
Using the new Feed class, these feeds can be deployed directly as views:
from django.conf.urls.defaults import *
from myproject.feeds import LatestEntries, LatestEntriesByCategory
urlpatterns = patterns('',
# ...
(r'^feeds/latest/$', LatestEntries()),
(r'^feeds/categories/(?P<category_id>\d+)/$', LatestEntriesByCategory()),
# ...
)
If you currently use the feed()
view, the LatestEntries
class would
often not need to be modified apart from subclassing the new
Feed
class. The exception is if
Django was automatically working out the name of the template to use to render
the feed’s description and title elements (if you were not specifying the
title_template
and description_template
attributes). You should ensure
that you always specify title_template
and description_template
attributes, or provide item_title()
and item_description()
methods.
However, LatestEntriesByCategory
uses the get_object()
method
with the bits
argument to specify a specific category to show. In
the new Feed
class,
get_object()
method takes a request
and arguments from the
URL, so it would look like this:
from django.contrib.syndication.views import Feed
from django.shortcuts import get_object_or_404
from myproject.models import Category
class LatestEntriesByCategory(Feed):
def get_object(self, request, category_id):
return get_object_or_404(Category, id=category_id)
# ...
Additionally, the get_feed()
method on Feed
classes now take
different arguments, which may impact you if you use the Feed
classes directly. Instead of just taking an optional url
argument,
it now takes two arguments: the object returned by its own
get_object()
method, and the current request
object.
To take into account Feed
classes not being initialized for each
request, the __init__()
method now takes no arguments by default.
Previously it would have taken the slug
from the URL and the
request
object.
In accordance with RSS best practices, RSS feeds will now include
an atom:link
element. You may need to update your tests to take
this into account.
For more information, see the full syndication framework documentation.
Technical message IDs¶
Up to version 1.1 Django used technical message IDs
to provide localizers the possibility to translate date and time formats. They
were translatable translation strings that could
be recognized because they were all upper case (for example
DATETIME_FORMAT
, DATE_FORMAT
, TIME_FORMAT
).
They have been deprecated in favor of the new Format localization
infrastructure that allows localizers to specify that information in a
formats.py
file in the corresponding django/conf/locale/<locale name>/
directory.
GeoDjango¶
To allow support for multiple databases, the GeoDjango database internals were
changed substantially. The largest backwards-incompatible change is that
the module django.contrib.gis.db.backend
was renamed to
django.contrib.gis.db.backends
, where the full-fledged
spatial database backends now exist. The
following sections provide information on the most-popular APIs that
were affected by these changes.
SpatialBackend
¶
Prior to the creation of the separate spatial backends, the
django.contrib.gis.db.backend.SpatialBackend
object was
provided as an abstraction to introspect on the capabilities of
the spatial database. All of the attributes and routines provided by
SpatialBackend
are now a part of the ops
attribute of the
database backend.
The old module django.contrib.gis.db.backend
is still provided
for backwards-compatibility access to a SpatialBackend
object,
which is just an alias to the ops
module of the
default spatial database connection.
Users that were relying on undocumented modules and objects
within django.contrib.gis.db.backend
, rather the abstractions
provided by SpatialBackend
, are required to modify their code.
For example, the following import which would work in 1.1 and
below:
from django.contrib.gis.db.backend.postgis import PostGISAdaptor
Would need to be changed:
from django.db import connection
PostGISAdaptor = connection.ops.Adapter
SpatialRefSys
and GeometryColumns
models¶
In previous versions of GeoDjango, django.contrib.gis.db.models
had SpatialRefSys
and GeometryColumns
models for querying
the OGC spatial metadata tables spatial_ref_sys
and geometry_columns
,
respectively.
While these aliases are still provided, they are only for the default database connection and exist only if the default connection is using a supported spatial database backend.
Note
Because the table structure of the OGC spatial metadata tables
differs across spatial databases, the SpatialRefSys
and
GeometryColumns
models can no longer be associated with
the gis
application name. Thus, no models will be returned
when using the get_models
method in the following example:
>>> from django.db.models import get_app, get_models
>>> get_models(get_app('gis'))
[]
To get the correct SpatialRefSys
and GeometryColumns
for your spatial database use the methods provided by the spatial backend:
>>> from django.db import connections
>>> SpatialRefSys = connections['my_spatialite'].ops.spatial_ref_sys()
>>> GeometryColumns = connections['my_postgis'].ops.geometry_columns()
Note
When using the models returned from the spatial_ref_sys()
and
geometry_columns()
method, you’ll still need to use the
correct database alias when querying on the non-default connection.
In other words, to ensure that the models in the example above
use the correct database:
sr_qs = SpatialRefSys.objects.using('my_spatialite').filter(...)
gc_qs = GeometryColumns.objects.using('my_postgis').filter(...)
Language code no
¶
The currently used language code for Norwegian Bokmål no
is being
replaced by the more common language code nb
.
Function-based template loaders¶
Django 1.2 changes the template loading mechanism to use a class-based approach. Old style function-based template loaders will still work, but should be updated to use the new class-based template loaders.