Migrating to 1.0

The 1.0 release of django-filter introduces several API changes and refinements that break forwards compatibility. Below is a list of deprecations and instructions on how to migrate to the 1.0 release. A forwards-compatible 0.15 release has also been created to help with migration. It is compatible with both the existing and new APIs and will raise warnings for deprecated behavior.

Enabling warnings

To view the deprecations, you may need to enable warnings within python. This can be achieved with either the -W flag, or with PYTHONWARNINGS environment variable. For example, you could run your test suite like so:

$ python -W once manage.py test

The above would print all warnings once when they first occur. This is useful to know what violations exist in your code (or occasionally in third party code). However, it only prints the last line of the stack trace. You can use the following to raise the full exception instead:

$ python -W error manage.py test

MethodFilter and Filter.action replaced by Filter.method

Details: https://github.com/carltongibson/django-filter/pull/382

The functionality of MethodFilter and Filter.action has been merged together and replaced by the Filter.method parameter. The method parameter takes either a callable or the name of a FilterSet method. The signature now takes an additional name argument that is the name of the model field to be filtered on.

Since method is now a parameter of all filters, inputs are validated and cleaned by its field_class. The function will receive the cleaned value instead of the raw value.

# 0.x
class UserFilter(FilterSet):
    last_login = filters.MethodFilter()

    def filter_last_login(self, qs, value):
        # try to convert value to datetime, which may fail.
        if value and looks_like_a_date(value):
            value = datetime(value)

        return qs.filter(last_login=value})


# 1.0
class UserFilter(FilterSet):
    last_login = filters.CharFilter(method='filter_last_login')

    def filter_last_login(self, qs, name, value):
        return qs.filter(**{name: value})

QuerySet methods are no longer proxied

Details: https://github.com/carltongibson/django-filter/pull/440

The __iter__(), __len__(), __getitem__(), count() methods are no longer proxied from the queryset. To fix this, call the methods on the .qs property itself.

f = UserFilter(request.GET, queryset=User.objects.all())

# 0.x
for obj in f:
    ...

# 1.0
for obj in f.qs:
    ...

Filters no longer autogenerated when Meta.fields is not specified

Details: https://github.com/carltongibson/django-filter/pull/450

FilterSets had an undocumented behavior of autogenerating filters for all model fields when either Meta.fields was not specified or when set to None. This can lead to potentially unsafe data or schema exposure and has been deprecated in favor of explicitly setting Meta.fields to the '__all__' special value. You may also blacklist fields by setting the Meta.exclude attribute.

class UserFilter(FilterSet):
    class Meta:
        model = User
        fields = '__all__'

# or
class UserFilter(FilterSet):
    class Meta:
        model = User
        exclude = ['password']

Move FilterSet options to Meta class

Details: https://github.com/carltongibson/django-filter/issues/430

Several FilterSet options have been moved to the Meta class to prevent potential conflicts with declared filter names. This includes:

  • filter_overrides
  • strict
  • order_by_field
# 0.x
class UserFilter(FilterSet):
    filter_overrides = {}
    strict = STRICTNESS.RAISE_VALIDATION_ERROR
    order_by_field = 'order'
    ...

# 1.0
class UserFilter(FilterSet):
    ...

    class Meta:
        filter_overrides = {}
        strict = STRICTNESS.RAISE_VALIDATION_ERROR
        order_by_field = 'order'

FilterSet ordering replaced by OrderingFilter

Details: https://github.com/carltongibson/django-filter/pull/472

The FilterSet ordering options and methods have been deprecated and replaced by OrderingFilter. Deprecated options include:

  • Meta.order_by
  • Meta.order_by_field

These options retain backwards compatibility with the following caveats:

  • order_by asserts that Meta.fields is not using the dict syntax. This previously was undefined behavior, however the migration code is unable to support it.

  • Prior, if no ordering was specified in the request, the FilterSet implicitly filtered by the first param in the order_by option. This behavior cannot be easily emulated but can be fixed by ensuring that the passed in queryset explicitly calls .order_by().

    filterset = MyFilterSet(queryset=MyModel.objects.order_by('field'))
    

The following methods are deprecated and will raise an assertion if present on the FilterSet:

  • .get_order_by()
  • .get_ordering_field()

To fix this, simply remove the methods from your class. You can subclass OrderingFilter to migrate any custom logic.

Deprecated FILTERS_HELP_TEXT_FILTER and FILTERS_HELP_TEXT_EXCLUDE

Details: https://github.com/carltongibson/django-filter/pull/437

Generated filter labels in 1.0 will be more descriptive, including humanized text about the lookup being performed and if the filter is an exclusion filter.

These settings will no longer have an effect and will be removed in the 1.0 release.