Django 1.0 breaks compatibility with 0.96 in some areas.
This guide will help you port 0.96 projects and apps to 1.0. The first part of this document includes the common changes needed to run with 1.0. If after going through the first part your code still breaks, check the section Less-common Changes for a list of a bunch of less-common compatibility issues.
See also
The 1.0 release notes. That document explains the new features in 1.0 more deeply; the porting guide is more concerned with helping you quickly update your code.
This section describes the changes between 0.96 and 1.0 that most users will need to make.
Change string literals ('foo') into Unicode literals (u'foo'). Django
now uses Unicode strings throughout. In most places, raw strings will continue
to work, but updating to use Unicode literals will prevent some obscure
problems.
See Unicode data for full details.
Common changes to your models file:
maxlength to max_length¶Rename your maxlength argument to max_length (this was changed to be
consistent with form fields):
__str__ with __unicode__¶Replace your model’s __str__ function with a __unicode__ method, and
make sure you use Unicode (u'foo') in that method.
prepopulated_from¶Remove the prepopulated_from argument on model fields. It’s no longer valid
and has been moved to the ModelAdmin class in admin.py. See the
admin, below, for more details about changes to the admin.
core¶Remove the core argument from your model fields. It is no longer
necessary, since the equivalent functionality (part of inline editing) is handled differently by the admin interface now. You don’t
have to worry about inline editing until you get to the admin section,
below. For now, remove all references to core.
class Admin: with admin.py¶Remove all your inner class Admin declarations from your models. They won’t
break anything if you leave them, but they also won’t do anything. To register
apps with the admin you’ll move those declarations to an admin.py file;
see the admin below for more details.
See also
A contributor to djangosnippets has written a script that’ll scan your models.py and generate a corresponding admin.py.
Below is an example models.py file with all the changes you’ll need to make:
Old (0.96) models.py:
class Author(models.Model):
first_name = models.CharField(maxlength=30)
last_name = models.CharField(maxlength=30)
slug = models.CharField(maxlength=60, prepopulate_from=('first_name', 'last_name'))
class Admin:
list_display = ['first_name', 'last_name']
def __str__(self):
return '%s %s' % (self.first_name, self.last_name)
New (1.0) models.py:
class Author(models.Model):
first_name = models.CharField(max_length=30)
last_name = models.CharField(max_length=30)
slug = models.CharField(max_length=60)
def __unicode__(self):
return u'%s %s' % (self.first_name, self.last_name)
New (1.0) admin.py:
from django.contrib import admin
from models import Author
class AuthorAdmin(admin.ModelAdmin):
list_display = ['first_name', 'last_name']
prepopulated_fields = {
'slug': ('first_name', 'last_name')
}
admin.site.register(Author, AuthorAdmin)
One of the biggest changes in 1.0 is the new admin. The Django administrative
interface (django.contrib.admin) has been completely refactored; admin
definitions are now completely decoupled from model definitions, the framework
has been rewritten to use Django’s new form-handling library and redesigned with
extensibility and customization in mind.
Practically, this means you’ll need to rewrite all of your class Admin
declarations. You’ve already seen in models above how to replace your class
Admin with a admin.site.register() call in an admin.py file. Below are
some more details on how to rewrite that Admin declaration into the new
syntax.
The new edit_inline options have all been moved to admin.py. Here’s an
example:
Old (0.96):
class Parent(models.Model):
...
class Child(models.Model):
parent = models.ForeignKey(Parent, edit_inline=models.STACKED, num_in_admin=3)
New (1.0):
class ChildInline(admin.StackedInline):
model = Child
extra = 3
class ParentAdmin(admin.ModelAdmin):
model = Parent
inlines = [ChildInline]
admin.site.register(Parent, ParentAdmin)
See InlineModelAdmin objects for more details.
fields, or use fieldsets¶The old fields syntax was quite confusing, and has been simplified. The old
syntax still works, but you’ll need to use fieldsets instead.
Old (0.96):
class ModelOne(models.Model):
...
class Admin:
fields = (
(None, {'fields': ('foo','bar')}),
)
class ModelTwo(models.Model):
...
class Admin:
fields = (
('group1', {'fields': ('foo','bar'), 'classes': 'collapse'}),
('group2', {'fields': ('spam','eggs'), 'classes': 'collapse wide'}),
)
New (1.0):
class ModelOneAdmin(admin.ModelAdmin):
fields = ('foo', 'bar')
class ModelTwoAdmin(admin.ModelAdmin):
fieldsets = (
('group1', {'fields': ('foo','bar'), 'classes': 'collapse'}),
('group2', {'fields': ('spam','eggs'), 'classes': 'collapse wide'}),
)
See also
urls.py¶If you’re using the admin site, you need to update your root urls.py.
Old (0.96) urls.py:
from django.conf.urls.defaults import *
urlpatterns = patterns('',
(r'^admin/', include('django.contrib.admin.urls')),
# ... the rest of your URLs here ...
)
New (1.0) urls.py:
from django.conf.urls.defaults import *
# The next two lines enable the admin and load each admin.py file:
from django.contrib import admin
admin.autodiscover()
urlpatterns = patterns('',
(r'^admin/(.*)', admin.site.root),
# ... the rest of your URLs here ...
)
django.forms instead of newforms¶Replace django.newforms with django.forms – Django 1.0 renamed the
newforms module (introduced in 0.96) to plain old forms. The
oldforms module was also removed.
If you’re already using the newforms library, and you used our recommended
import statement syntax, all you have to do is change your import
statements.
Old:
from django import newforms as forms
New:
from django import forms
If you’re using the old forms system (formerly known as django.forms and
django.oldforms), you’ll have to rewrite your forms. A good place to start
is the forms documentation
Replace use of uploaded files – that is, entries in request.FILES – as
simple dictionaries with the new
UploadedFile. The old dictionary
syntax no longer works.
Thus, in a view like:
def my_view(request):
f = request.FILES['file_field_name']
...
…you’d need to make the following changes:
| Old (0.96) | New (1.0) |
|---|---|
f['content'] |
f.read() |
f['filename'] |
f.name |
f['content-type'] |
f.content_type |
The internal implementation of django.db.models.FileField have changed.
A visible result of this is that the way you access special attributes (URL,
filename, image size, etc.) of these model fields has changed. You will need to
make the following changes, assuming your model’s
FileField is called myfile:
| Old (0.96) | New (1.0) |
|---|---|
myfile.get_content_filename() |
myfile.content.path |
myfile.get_content_url() |
myfile.content.url |
myfile.get_content_size() |
myfile.content.size |
myfile.save_content_file() |
myfile.content.save() |
myfile.get_content_width() |
myfile.content.width |
myfile.get_content_height() |
myfile.content.height |
Note that the width and height attributes only make sense for
ImageField fields. More details can be found in the
model API documentation.
Paginator instead of ObjectPaginator¶The ObjectPaginator in 0.96 has been removed and replaced with an improved
version, django.core.paginator.Paginator.
By default, the template system now automatically HTML-escapes the output of every variable. To learn more, see Automatic HTML escaping.
To disable auto-escaping for an individual variable, use the safe
filter:
This will be escaped: {{ data }}
This will not be escaped: {{ data|safe }}
To disable auto-escaping for an entire template, wrap the template (or just a
particular section of the template) in the autoescape tag:
{% autoescape off %}
... unescaped template content here ...
{% endautoescape %}
The following changes are smaller, more localized changes. They should only affect more advanced users, but it’s probably worth reading through the list and checking your code for these things.
**kwargs to any registered signal handlers.Signal object instead of through module methods in
django.dispatch.dispatcher.Anonymous and Any sender options; they no longer
exist. You can still receive signals sent by any sender by using
sender=Nonedjango.dispatch.Signal instead of anonymous objects.Here’s quick summary of the code changes you’ll need to make:
| Old (0.96) | New (1.0) |
|---|---|
def callback(sender) |
def callback(sender, **kwargs) |
sig = object() |
sig = django.dispatch.Signal() |
dispatcher.connect(callback, sig) |
sig.connect(callback) |
dispatcher.send(sig, sender) |
sig.send(sender) |
dispatcher.connect(callback, sig, sender=Any) |
sig.connect(callback, sender=None) |
If you were using Django 0.96’s django.contrib.comments app, you’ll need to
upgrade to the new comments app introduced in 1.0. See the upgrade guide
for details.
django.contrib.localflavor.usa has been renamed to
django.contrib.localflavor.us. This change was made to match the naming
scheme of other local flavors. To migrate your code, all you need to do is
change the imports.
SessionBase.get_new_session_key() has been renamed to
_get_new_session_key(). get_new_session_object() no longer exists.
save()¶Previously, loading a row automatically ran the model’s save() method. This
is no longer the case, so any fields (for example: timestamps) that were
auto-populated by a save() now need explicit values in any fixture.
The old EnvironmentError has split into an
ImportError when Django fails to find the settings module
and a RuntimeError when you try to reconfigure settings
after having already used them.
LOGIN_URL has moved¶The LOGIN_URL constant moved from django.contrib.auth into the
settings module. Instead of using from django.contrib.auth import
LOGIN_URL refer to settings.LOGIN_URL.
APPEND_SLASH behavior has been updated¶In 0.96, if a URL didn’t end in a slash or have a period in the final
component of its path, and APPEND_SLASH was True, Django would
redirect to the same URL, but with a slash appended to the end. Now, Django
checks to see whether the pattern without the trailing slash would be matched
by something in your URL patterns. If so, no redirection takes place, because
it is assumed you deliberately wanted to catch that pattern.
For most people, this won’t require any changes. Some people, though, have URL patterns that look like this:
r'/some_prefix/(.*)$'
Previously, those patterns would have been redirected to have a trailing slash. If you always want a slash on such URLs, rewrite the pattern as:
r'/some_prefix/(.*/)$'
get()¶Managers now return a MultipleObjectsReturned
exception instead of AssertionError:
Old (0.96):
try:
Model.objects.get(...)
except AssertionError:
handle_the_error()
New (1.0):
try:
Model.objects.get(...)
except Model.MultipleObjectsReturned:
handle_the_error()
LazyDate has been fired¶The LazyDate helper class no longer exists.
Default field values and query arguments can both be callable objects, so
instances of LazyDate can be replaced with a reference to datetime.datetime.now:
Old (0.96):
class Article(models.Model):
title = models.CharField(maxlength=100)
published = models.DateField(default=LazyDate())
New (1.0):
import datetime
class Article(models.Model):
title = models.CharField(max_length=100)
published = models.DateField(default=datetime.datetime.now)
DecimalField is new, and FloatField is now a proper float¶Old (0.96):
class MyModel(models.Model):
field_name = models.FloatField(max_digits=10, decimal_places=3)
...
New (1.0):
class MyModel(models.Model):
field_name = models.DecimalField(max_digits=10, decimal_places=3)
...
If you forget to make this change, you will see errors about FloatField
not taking a max_digits attribute in __init__, because the new
FloatField takes no precision-related arguments.
If you’re using MySQL or PostgreSQL, no further changes are needed. The
database column types for DecimalField are the same as for the old
FloatField.
If you’re using SQLite, you need to force the database to view the
appropriate columns as decimal types, rather than floats. To do this, you’ll
need to reload your data. Do this after you have made the change to using
DecimalField in your code and updated the Django code.
Warning
Back up your database first!
For SQLite, this means making a copy of the single file that stores the
database (the name of that file is the DATABASE_NAME in your
settings.py file).
To upgrade each application to use a DecimalField, you can do the
following, replacing <app> in the code below with each app’s name:
$ ./manage.py dumpdata --format=xml <app> > data-dump.xml
$ ./manage.py reset <app>
$ ./manage.py loaddata data-dump.xml
Notes:
DecimalField is not used in any of the apps shipped with Django prior
to this change being made, so you do not need to worry about performing
this procedure for any of the standard Django models.If something goes wrong in the above process, just copy your backed up database file over the original file and start again.
django.views.i18n.set_language() now requires a POST request¶Previously, a GET request was used. The old behavior meant that state (the locale used to display the site) could be changed by a GET request, which is against the HTTP specification’s recommendations. Code calling this view must ensure that a POST request is now made, instead of a GET. This means you can no longer use a link to access the view, but must use a form submission of some kind (e.g. a button).
_() is no longer in builtins¶_() (the callable object whose name is a single underscore) is no longer
monkeypatched into builtins – that is, it’s no longer available magically in
every module.
If you were previously relying on _() always being present, you should now
explicitly import ugettext or ugettext_lazy, if appropriate, and alias
it to _ yourself:
from django.utils.translation import ugettext as _
HttpRequest¶HttpRequest objects no longer directly support dictionary-style
access; previously, both GET and POST data were directly
available on the HttpRequest object (e.g., you could check for a
piece of form data by using if 'some_form_key' in request or by
reading request['some_form_key']. This is no longer supported; if
you need access to the combined GET and POST data, use
request.REQUEST instead.
It is strongly suggested, however, that you always explicitly look in
the appropriate dictionary for the type of request you expect to
receive (request.GET or request.POST); relying on the combined
request.REQUEST dictionary can mask the origin of incoming data.
HTTPResponse headers¶django.http.HttpResponse.headers has been renamed to _headers and
HttpResponse now supports containment checking directly.
So use if header in response: instead of if header in response.headers:.
The generic relation classes – GenericForeignKey and GenericRelation
– have moved into the django.contrib.contenttypes module.
django.test.Client.login() has changed¶Old (0.96):
from django.test import Client
c = Client()
c.login('/path/to/login','myuser','mypassword')
New (1.0):
# ... same as above, but then:
c.login(username='myuser', password='mypassword')
django.core.management has been greatly refactored.
Calls to management services in your code now need to use
call_command. For example, if you have some test code that calls flush and
load_data:
from django.core import management
management.flush(verbosity=0, interactive=False)
management.load_data(['test_data'], verbosity=0)
…you’ll need to change this code to read:
from django.core import management
management.call_command('flush', verbosity=0, interactive=False)
management.call_command('loaddata', 'test_data', verbosity=0)
django-admin.py and manage.py now require subcommands to precede
options. So:
$ django-admin.py --settings=foo.bar runserver
…no longer works and should be changed to:
$ django-admin.py runserver --settings=foo.bar
Feed.__init__ has changed¶The __init__() method of the syndication framework’s Feed class now
takes an HttpRequest object as its second parameter, instead of the feed’s
URL. This allows the syndication framework to work without requiring the sites
framework. This only affects code that subclasses Feed and overrides the
__init__() method, and code that calls Feed.__init__() directly.
SortedDictFromList is gone¶django.newforms.forms.SortedDictFromList was removed.
django.utils.datastructures.SortedDict can now be instantiated with
a sequence of tuples.
To update your code:
django.utils.datastructures.SortedDict wherever you were
using django.newforms.forms.SortedDictFromList.django.utils.datastructures.SortedDict.copy doesn’t
return a deepcopy as SortedDictFromList.copy() did, you will need
to update your code if you were relying on a deepcopy. Do this by using
copy.deepcopy directly.Almost all of the database backend-level functions have been renamed and/or
relocated. None of these were documented, but you’ll need to change your code
if you’re using any of these functions, all of which are in django.db:
| Old (0.96) | New (1.0) |
|---|---|
backend.get_autoinc_sql |
connection.ops.autoinc_sql |
backend.get_date_extract_sql |
connection.ops.date_extract_sql |
backend.get_date_trunc_sql |
connection.ops.date_trunc_sql |
backend.get_datetime_cast_sql |
connection.ops.datetime_cast_sql |
backend.get_deferrable_sql |
connection.ops.deferrable_sql |
backend.get_drop_foreignkey_sql |
connection.ops.drop_foreignkey_sql |
backend.get_fulltext_search_sql |
connection.ops.fulltext_search_sql |
backend.get_last_insert_id |
connection.ops.last_insert_id |
backend.get_limit_offset_sql |
connection.ops.limit_offset_sql |
backend.get_max_name_length |
connection.ops.max_name_length |
backend.get_pk_default_value |
connection.ops.pk_default_value |
backend.get_random_function_sql |
connection.ops.random_function_sql |
backend.get_sql_flush |
connection.ops.sql_flush |
backend.get_sql_sequence_reset |
connection.ops.sequence_reset_sql |
backend.get_start_transaction_sql |
connection.ops.start_transaction_sql |
backend.get_tablespace_sql |
connection.ops.tablespace_sql |
backend.quote_name |
connection.ops.quote_name |
backend.get_query_set_class |
connection.ops.query_set_class |
backend.get_field_cast_sql |
connection.ops.field_cast_sql |
backend.get_drop_sequence |
connection.ops.drop_sequence_sql |
backend.OPERATOR_MAPPING |
connection.operators |
backend.allows_group_by_ordinal |
connection.features.allows_group_by_ordinal |
backend.allows_unique_and_pk |
connection.features.allows_unique_and_pk |
backend.autoindexes_primary_keys |
connection.features.autoindexes_primary_keys |
backend.needs_datetime_string_cast |
connection.features.needs_datetime_string_cast |
backend.needs_upper_for_iops |
connection.features.needs_upper_for_iops |
backend.supports_constraints |
connection.features.supports_constraints |
backend.supports_tablespaces |
connection.features.supports_tablespaces |
backend.uses_case_insensitive_names |
connection.features.uses_case_insensitive_names |
backend.uses_custom_queryset |
connection.features.uses_custom_queryset |
Jul 24, 2018