October 25, 2012.
Welcome to Django 1.5 alpha!
This is the first in a series of preview/development releases leading up to the eventual release of Django 1.5, scheduled for December 2012. This release is primarily targeted at developers who are interested in trying out new features and testing the Django codebase to help identify and resolve bugs prior to the final 1.5 release.
As such, this release is not intended for production use, and any such use is discouraged.
In particular, we need the community’s help to test Django 1.5’s new Python 3 support – not just to report bugs on Python 3, but also regressions on Python 2. While Django is very conservative with regards to backwards compatibility, mistakes are always possible, and it’s likely that the Python 3 refactoring work introduced some regressions.
Django 1.5 alpha includes various new features and some minor backwards incompatible changes. There are also some features that have been dropped, which are detailed in our deprecation plan, and we’ve begun the deprecation process for some features.
The biggest new feature in Django 1.5 is the configurable User model. Before
Django 1.5, applications that wanted to use Django’s auth framework
(django.contrib.auth
) were forced to use Django’s definition of a “user”.
In Django 1.5, you can now swap out the User
model for one that you write
yourself. This could be a simple extension to the existing User
model – for
example, you could add a Twitter or Facebook ID field – or you could completely
replace the User
with one totally customized for your site.
Django 1.5 is also the first release with Python 3 support! We’re labeling this support “experimental” because we don’t yet consider it production-ready, but everything’s in place for you to start porting your apps to Python 3. Our next release, Django 1.6, will support Python 3 without reservations.
Other notable new features in Django 1.5 include:
Model.save()
now accepts an
update_fields
argument, letting you specify which fields are
written back to the database when you call save()
. This can help
in high-concurrency operations, and can improve performance.StreamingHttpResponse
response class.Wherever possible we try to introduce new features in a backwards-compatible manner per our API stability policy policy. However, as with previous releases, Django 1.5 ships with some minor backwards incompatible changes; people upgrading from previous versions of Django should read that list carefully.
One deprecated feature worth noting is the shift to “new-style” url
tag.
Prior to Django 1.3, syntax like {% url myview %}
was interpreted
incorrectly (Django considered "myview"
to be a literal name of a view, not
a template variable named myview
). Django 1.3 and above introduced the
{% load url from future %}
syntax to bring in the corrected behavior where
myview
was seen as a variable.
The upshot of this is that if you are not using {% load url from future %}
in your templates, you’ll need to change tags like {% url myview %}
to
{% url "myview" %}
. If you were using {% load url from future %}
you
can simply remove that line under Django 1.5
Django 1.5 requires Python 2.6.5 or above, though we highly recommended Python 2.7.3 or above. Support for Python 2.5 and below has been dropped.
This change should affect only a small number of Django users, as most operating-system vendors today are shipping Python 2.6 or newer as their default version. If you’re still using Python 2.5, however, you’ll need to stick to Django 1.4 until you can upgrade your Python version. Per our support policy, Django 1.4 will continue to receive security support until the release of Django 1.6.
Django 1.5 does not run on a Jython final release, because Jython’s latest release doesn’t currently support Python 2.6. However, Jython currently does offer an alpha release featuring 2.7 support, and Django 1.5 supports that alpha release.
Django 1.5 introduces support for Python 3 - specifically, Python 3.2 and above. This comes in the form of a single codebase; you don’t need to install a different version of Django on Python 3. This means that you can write application targeted for just Python 2, just Python 3, or single applications that support both platforms.
However, we’re labeling this support “experimental” for now: although it’s received extensive testing via our automated test suite, it’s received very little real-world testing. We’ve done our best to eliminate bugs, but we can’t be sure we covered all possible uses of Django. Further, Django’s more than a web framework; it’s an ecosystem of pluggable components. At this point, very few third-party applications have been ported to Python 3, so it’s unlikely that a real-world application will have all its dependencies satisfied under Python 3.
Thus, we’re recommending that Django 1.5 not be used in production under Python 3. Instead, use this opportunity to begin porting applications to Python 3. If you’re an author of a pluggable component, we encourage you to start porting now.
We plan to offer first-class, production-ready support for Python 3 in our next release, Django 1.6.
In Django 1.5, you can now use your own model as the store for user-related data. If your project needs a username with more than 30 characters, or if you want to store usernames in a format other than first name/last name, or you want to put custom profile information onto your User object, you can now do so.
If you have a third-party reusable application that references the User model, you may need to make some changes to the way you reference User instances. You should also document any specific features of the User model that your application relies upon.
See the documentation on custom User models for more details.
The method Model.save()
has a new
keyword argument update_fields
. By using this argument it is possible to
save only a select list of model’s fields. This can be useful for performance
reasons or when trying to avoid overwriting concurrent changes.
Deferred instances (those loaded by .only() or .defer()) will automatically save just the loaded fields. If any field is set manually after load, that field will also get updated on save.
See the Model.save()
documentation for
more details.
Before Django 1.5, it was possible to create a streaming response by passing
an iterator to HttpResponse
. But this was unreliable:
any middleware that accessed the content
attribute would consume the iterator prematurely.
You can now explicitly generate a streaming response with the new
StreamingHttpResponse
class. This class exposes a
streaming_content
attribute which
is an iterator.
Since StreamingHttpResponse
does not have a content
attribute, middleware that needs access to the response content must test for
streaming responses and behave accordingly. See process_response for
more information.
{% verbatim %}
template tag¶To make it easier to deal with javascript templates which collide with Django’s
syntax, you can now use the verbatim
block tag to avoid parsing the
tag’s content.
ContentType
instances associated with proxy models¶The methods ContentTypeManager.get_for_model()
and ContentTypeManager.get_for_models()
have a new keyword argument – respectively for_concrete_model
and for_concrete_models
.
By passing False
using this argument it is now possible to retrieve the
ContentType
associated with proxy models.
view
variable in class-based views context¶In all generic class-based views
(or any class-based view inheriting from ContextMixin
), the context dictionary
contains a view
variable that points to the View
instance.
LineString
and
MultiLineString
GEOS objects now support the
interpolate()
and
project()
methods
(so-called linear referencing).wkb
and hex
properties of
GEOSGeometry
objects preserve the Z
dimension.Django 1.5 also includes several smaller improvements worth noting:
True
, False
and None
as the
corresponding Python objects.django.utils.timezone
provides a helper for converting aware
datetimes between time zones. See localtime()
.SystemExit
any more when called by code
from call_command. Any exception raised by the command
(mostly CommandError) is propagated.QuerySet.bulk_create()
now has a batch_size
argument. By default the batch_size is unlimited except for SQLite where
single batch is limited so that 999 parameters per query isn’t exceeded.LOGIN_URL
and LOGIN_REDIRECT_URL
settings now also
accept view function names and
named URL patterns. This allows you to reduce
configuration duplication. More information can be found in the
login_required()
documentation.QuerySet.delete()
and Model.delete()
can now take
fast-path in some cases. The fast-path allows for less queries and less
objects fetched into memory. See QuerySet.delete()
for details.ResolverMatch
is stored on
the request as resolver_match
.django
logger when
DEBUG
is True
are sent to the console (unless you redefine the
logger in your LOGGING
setting).RequestContext
, it is now possible to
look up permissions by using {% if 'someapp.someperm' in perms %}
in templates.404.html
and 500.html
templates in
the root templates directory. Django will output some basic error messages for
both situations when those templates are not found. Of course, it’s still
recommended as good practice to provide those templates in order to present
pretty error pages to the user.django.contrib.auth
provides a new signal that is emitted
whenever a user fails to login successfully. See
user_login_failed
--ignorenonexistent
option to ignore data for fields that no
longer exist.assertXMLEqual()
and
assertXMLNotEqual()
new assertions allow
you to test equality for XML content at a semantic level, without caring for
syntax differences (spaces, attribute order, etc.).警告
In addition to the changes outlined in this section, be sure to review the deprecation plan 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.
For consistency with the other date-based generic views,
YearArchiveView
now passes year
in
the context as a datetime.date
rather than a string. If you are
using {{ year }}
in your templates, you must replace it with {{
year|date:"Y" }}
.
next_year
and previous_year
were also added in the context. They are
calculated according to allow_empty
and allow_future
.
YearArchiveView
and
MonthArchiveView
were documented to
provide a date_list
sorted in ascending order in the context, like their
function-based predecessors, but it actually was in descending order. In 1.5,
the documented order was restored. You may want to add (or remove) the
reversed
keyword when you’re iterating on date_list
in a template:
{% for date in date_list reversed %}
ArchiveIndexView
still provides a
date_list
in descending order.
For consistency with the design of the other generic views,
TemplateView
no longer passes a params
dictionary into the context, instead passing the variables from the URLconf
directly into the context.
request.POST
will no longer include data
posted via HTTP requests with non form-specific content-types in the header.
In prior versions, data posted with content-types other than
multipart/form-data
or application/x-www-form-urlencoded
would still
end up represented in the request.POST
attribute. Developers wishing to access the raw POST data for these cases,
should use the request.body
attribute
instead.
Unlike GET and POST, these HTTP methods aren’t implemented by web browsers. Rather, they’re used in APIs, which transfer data in various formats such as JSON or XML. Since such requests may contain arbitrary data, Django doesn’t attempt to decode their body.
However, the test client used to build a query string for OPTIONS and DELETE requests like for GET, and a request body for PUT requests like for POST. This encoding was arbitrary and inconsistent with Django’s behavior when it receives the requests, so it was removed in Django 1.5.
If you were using the data
parameter in an OPTIONS or a DELETE request,
you must convert it to a query string and append it to the path
parameter.
If you were using the data
parameter in a PUT request without a
content_type
, you must encode your data before passing it to the test
client and set the content_type
argument.
simplejson
no longer used¶As explained below, Django 1.5 deprecates
django.utils.simplejson
in favor of Python 2.6’s built-in json
module. In theory, this change is harmless. Unfortunately, because of
incompatibilities between versions of simplejson
, it may trigger errors
in some circumstances.
JSON-related features in Django 1.4 always used django.utils.simplejson
.
This module was actually:
simplejson
, if one was available (ie. import
simplejson
works), if it was more recent than Django’s built-in copy or it
had the C speedups, orjson
module from the standard library, if it was available (ie.
Python 2.6 or greater), orsimplejson
.In Django 1.5, those features use Python’s json
module, which is based
on version 2.0.9 of simplejson
.
There are no known incompatibilities between Django’s copy of version 2.0.7 and
Python’s copy of version 2.0.9. However, there are some incompatibilities
between other versions of simplejson
:
simplejson
API is documented as always returning unicode
strings, the optional C implementation can return a byte string. This was
fixed in Python 2.7.simplejson.JSONEncoder
gained a namedtuple_as_object
keyword
argument in version 2.2.More information on these incompatibilities is available in ticket #18023.
The net result is that, if you have installed simplejson
and your code
uses Django’s serialization internals directly – for instance
django.core.serializers.json.DjangoJSONEncoder
, the switch from
simplejson
to json
could break your code. (In general, changes to
internals aren’t documented; we’re making an exception here.)
At this point, the maintainers of Django believe that using json
from
the standard library offers the strongest guarantee of backwards-compatibility.
They recommend to use it from now on.
If you have written a custom password hasher,
your encode()
, verify()
or safe_summary()
methods should accept
Unicode parameters (password
, salt
or encoded
). If any of the
hashing methods need byte strings, you can use the
force_bytes()
utility to encode the strings.
When using object pagination,
the previous_page_number()
and next_page_number()
methods of the
Page
object did not check if the returned
number was inside the existing page range.
It does check it now and raises an InvalidPage
exception when the number is either too low or too high.
PostgreSQL’s autocommit option didn’t work as advertised previously. It did work for single transaction block, but after the first block was left the autocommit behavior was never restored. This bug is now fixed in 1.5. While this is only a bug fix, it is worth checking your applications behavior if you are using PostgreSQL together with the autocommit option.
Django’s session middleware will skip saving the session data if the response’s status code is 500.
Prior to Django 1.5, if you attempted to log into the admin interface and mistakenly used your email address instead of your username, the admin interface would provide a warning advising that your email address was not your username. In Django 1.5, the introduction of custom User models has required the removal of this warning. This doesn’t change the login behavior of the admin site; it only affects the warning message that is displayed under one particular mode of login failure.
Some changes have been introduced in the execution of tests that might be backward-incompatible for some testing setups:
django.test.TransactionTestCase
¶Previously, the test database was truncated before each test run in a
TransactionTestCase
.
In order to be able to run unit tests in any order and to make sure they are
always isolated from each other, TransactionTestCase
will
now reset the database after each test run instead.
TransactionTestCase
tests used to reset primary key
sequences automatically together with the database flushing actions described
above.
This has been changed so no sequences are implicitly reset. This can cause
TransactionTestCase
tests that depend on hard-coded
primary key values to break.
The new reset_sequences
attribute can
be used to force the old behavior for TransactionTestCase
that might need it.
In order to make sure all TestCase
code starts with a clean database,
tests are now executed in the following order:
unittest.TestCase
,
SimpleTestCase
, TestCase
and
TransactionTestCase
) are run with no particular ordering
guaranteed nor enforced among them.This should not cause any problems unless you have existing doctests which
assume a TransactionTestCase
executed earlier left some
database state behind or unit tests that rely on some form of state being
preserved after the execution of other tests. Such tests are already very
fragile, and must now be changed to be able to run independently.
The cleaned_data
dictionary is now always present
after form validation. When the form doesn’t validate, it contains only the
fields that passed validation. You should test the success of the validation
with the is_valid()
method and not with the
presence or absence of the cleaned_data
attribute
on the form.
django.forms.ModelMultipleChoiceField
now returns an empty
QuerySet
as the empty value instead of an empty list.int_to_base36()
properly raises a
TypeError
instead of ValueError
for
non-integer inputs.slugify
template filter is now available as a standard python
function at django.utils.text.slugify()
. Similarly, remove_tags
is
available at django.utils.html.remove_tags()
.FILE_UPLOAD_PERMISSIONS
to your
needs. The new default value is 0666
(octal) and the current umask value
is first masked out.&
and |
. These operators are now available using .bitand()
and
.bitor()
instead. The removal of &
and |
was done to be consistent with
Q() expressions and QuerySet
combining where
the operators are used as boolean AND and OR operators.csrf_token
template tag is no longer enclosed in a div. If you need
HTML validation against pre-HTML5 Strict DTDs, you should add a div around it
in your pages.AUTH_PROFILE_MODULE
¶With the introduction of custom User models, there is no longer any need for a built-in mechanism to store user profile data.
You can still define user profiles models that have a one-to-one relation with
the User model - in fact, for many applications needing to associate data with
a User account, this will be an appropriate design pattern to follow. However,
the AUTH_PROFILE_MODULE
setting, and the
get_profile()
method for accessing
the user profile model, should not be used any longer.
HttpResponse
¶Django 1.5 deprecates the ability to stream a response by passing an iterator
to HttpResponse
. If you rely on this behavior, switch to
StreamingHttpResponse
. See above for more details.
In Django 1.7 and above, the iterator will be consumed immediately by
HttpResponse
.
django.utils.simplejson
¶Since Django 1.5 drops support for Python 2.5, we can now rely on the
json
module being available in Python’s standard library, so we’ve
removed our own copy of simplejson
. You should now import json
instead of django.utils.simplejson
.
Unfortunately, this change might have unwanted side-effects, because of
incompatibilities between versions of simplejson
– see the backwards-
incompatible changes section. If you rely on features added to simplejson
after it became Python’s json
, you should import simplejson
explicitly.
django.utils.encoding.StrAndUnicode
¶The StrAndUnicode
mix-in has been deprecated.
Define a __str__
method and apply the
python_2_unicode_compatible()
decorator instead.
django.utils.itercompat.product
¶The django.utils.itercompat.product
function has been deprecated. Use
the built-in itertools.product()
instead.
django.utils.markup
¶The markup contrib module has been deprecated and will follow an accelerated deprecation schedule. Direct use of python markup libraries or 3rd party tag libraries is preferred to Django maintaining this functionality in the framework.
9月 16, 2017