netbox/netbox/utilities/filters.py

87 lines
3.0 KiB
Python

from __future__ import unicode_literals
import itertools
import django_filters
from django import forms
from django.utils.encoding import force_text
from taggit.models import Tag
#
# Filters
#
class NumericInFilter(django_filters.BaseInFilter, django_filters.NumberFilter):
"""
Filters for a set of numeric values. Example: id__in=100,200,300
"""
pass
class NullableCharFieldFilter(django_filters.CharFilter):
"""
Allow matching on null field values by passing a special string used to signify NULL.
"""
null_value = 'NULL'
def filter(self, qs, value):
if value != self.null_value:
return super(NullableCharFieldFilter, self).filter(qs, value)
qs = self.get_method(qs)(**{'{}__isnull'.format(self.name): True})
return qs.distinct() if self.distinct else qs
class NullableModelMultipleChoiceField(forms.ModelMultipleChoiceField):
"""
This field operates like a normal ModelMultipleChoiceField except that it allows for one additional choice which is
used to represent a value of Null. This is accomplished by creating a new iterator which first yields the null
choice before entering the queryset iterator, and by ignoring the null choice during cleaning. The effect is similar
to defining a MultipleChoiceField with:
choices = [(0, 'None')] + [(x.id, x) for x in Foo.objects.all()]
However, the above approach forces immediate evaluation of the queryset, which can cause issues when calculating
database migrations.
"""
iterator = forms.models.ModelChoiceIterator
def __init__(self, null_value=0, null_label='-- None --', *args, **kwargs):
self.null_value = null_value
self.null_label = null_label
super(NullableModelMultipleChoiceField, self).__init__(*args, **kwargs)
def _get_choices(self):
if hasattr(self, '_choices'):
return self._choices
# Prepend the null choice to the queryset iterator
return itertools.chain(
[(self.null_value, self.null_label)],
self.iterator(self),
)
choices = property(_get_choices, forms.ChoiceField._set_choices)
def clean(self, value):
# Strip all instances of the null value before cleaning
if value is not None:
stripped_value = [x for x in value if x != force_text(self.null_value)]
else:
stripped_value = value
super(NullableModelMultipleChoiceField, self).clean(stripped_value)
return value
class TagFilter(django_filters.ModelMultipleChoiceFilter):
"""
Match on one or more assigned tags. If multiple tags are specified (e.g. ?tag=foo&tag=bar), the queryset is filtered
to objects matching all tags.
"""
def __init__(self, *args, **kwargs):
kwargs.setdefault('name', 'tags__slug')
kwargs.setdefault('to_field_name', 'slug')
kwargs.setdefault('conjoined', True)
kwargs.setdefault('queryset', Tag.objects.all())
super(TagFilter, self).__init__(*args, **kwargs)