Question

我正在使用django-filter和django-rest-framework，我正在尝试实例化一个过滤器，该过滤器接受用于过滤查询集的数字列表

class MyFilter(django_filters.FilterSet):   
    ids = django_filters.NumberFilter(name='id',lookup_type='in')
    class Meta:
        model = MyModel
        fields = ('ids',)

class MyModelViewSet(viewsets.ModelViewSet):
    queryset = MyModel.objects.all()
    serializer_class = MyModelSerializer
    filter_class = MyFilter

如果我传入逗号分隔的整数列表，则完全忽略过滤器。

如果我传入一个整数，它会通过django-filter进入django的表单验证器并抱怨：

'Decimal' object is not iterable

有没有办法创建一个django-filter对象，它可以处理整数列表并正确过滤掉查询集？

Answer 1

无论好坏，我为此创建了一个自定义过滤器：

class IntegerListFilter(django_filters.Filter):
    def filter(self,qs,value):
        if value not in (None,''):
            integers = [int(v) for v in value.split(',')]
            return qs.filter(**{'%s__%s'%(self.name, self.lookup_type):integers})
        return qs

使用方法如下：

class MyFilter(django_filters.FilterSet):   
    ids = IntegerListFilter(name='id',lookup_type='in')
    class Meta:
        model = MyModel
        fields = ('ids',)

class MyModelViewSet(viewsets.ModelViewSet):
    queryset = MyModel.objects.all()
    serializer_class = MyModelSerializer
    filter_class = MyFilter

现在我的界面接受以逗号分隔的整数列表。

Answer 2

这是一个完整的解决方案：

from django_filters import Filter, FilterSet
from rest_framework.filters import DjangoFilterBackend
from rest_framework.viewsets import ModelViewSet
from .models import User
from .serializers import UserSerializer


class ListFilter(Filter):

    def filter(self, qs, value):
        if not value:
            return qs

        self.lookup_type = 'in'
        values = value.split(',')
        return super(ListFilter, self).filter(qs, values)


class UserFilter(FilterSet):
    ids = ListFilter(name='id')

    class Meta:
        model = User
        fields = ['ids']


class UserViewSet(viewsets.ModelViewSet):
    serializer_class = UserSerializer
    queryset = User.objects.all()
    filter_backends = (DjangoFilterBackend,)
    filter_class = UserFilter

Answer 3

我知道这是一个老帖子，但现在有一个更好的解决方案。使其正确的更改已发布here。

他们添加了BaseInFilter和BaseRangeFilter。文档为here。

大图，BaseFilter检查CSV，然后当与另一个过滤器混合时，它会按照您的要求进行操作。您的代码现在可以写成：

class NumberInFilter(filters.BaseInFilter, filters.NumberFilter):
    pass

class MyModelViewSet(viewsets.ModelViewSet):
    ids = NumberInFilter(name='id', lookup_expr='in')

    class Meta:
        model = MyModel
        fields = ['ids']

Answer 4

根据django-filter issues中的帖子：

from django_filters import Filter
from django_filters.fields import Lookup

class ListFilter(Filter):
    def filter(self, qs, value):
        return super(ListFilter, self).filter(qs, Lookup(value.split(u","), "in"))

我亲自在我的项目中使用了这个，没有任何问题，而且无需创建每个类型的过滤器。

Answer 5

根据@yndolok的回答，我得出了一个通用的解决方案。我认为通过id列表进行过滤是一项非常常见的任务，因此应该包含在FilterBackend中：

class ListFilter(django_filters.Filter):

    """Class to filter from list of integers."""

    def filter(self, qs, value):
        """Filter function."""
        if not value:
            return qs
        self.lookup_type = 'in'
        try:
            map(int, value.split(','))
            return super(ListFilter, self).filter(qs, value.split(','))
        except ValueError:
            return super(ListFilter, self).filter(qs, [None])


class FilterBackend(filters.DjangoFilterBackend):

    """A filter backend that includes ListFilter."""

    def get_filter_class(self, view, queryset=None):
        """Append ListFilter to AutoFilterSet."""
        filter_fields = getattr(view, 'filter_fields', None)

        if filter_fields:
            class AutoFilterSet(self.default_filter_set):
                ids = ListFilter(name='id')

                class Meta:
                    model = queryset.model
                    fields = list(filter_fields) + ["ids"]

            return AutoFilterSet

        else:
            return super(FilterBackend, self).get_filter_class(view, queryset)

Answer 6

最新解决方案：

从django_filters导入rest_framework作为过滤器

名称-> field_name

lookup_type-> lookup_expr

class IntegerListFilter(filters.Filter):
    def filter(self,qs,value):
        if value not in (None,''):
            integers = [int(v) for v in value.split(',')]
            return qs.filter(**{'%s__%s'%(self.field_name, self.lookup_expr):integers})
        return qs

class MyFilter(filters.FilterSet):   
    ids = IntegerListFilter(field_name='id',lookup_expr='in')
    class Meta:
        model = MyModel
        fields = ('ids',)

class MyModelViewSet(viewsets.ModelViewSet):
    queryset = MyModel.objects.all()
    serializer_class = MyModelSerializer
    filter_class = MyFilter

Answer 7

正如我在这里DjangoFilterBackend with multiple ids所回答的那样，现在很容易制作一个可以接受列表并验证内容的过滤器

例如：


from django_filters import rest_framework as filters


class NumberInFilter(filters.BaseInFilter, filters.NumberFilter):
    pass

class MyFilter(filters.FilterSet):
    id_in = NumberInFilter(field_name='id', lookup_expr='in')

    class Meta:
        model = MyModel
        fields = ['id_in', ]

这将接受来自get参数的整数列表。例如/endpoint/?id_in=1,2,3

可以通过django-filter URL解析器执行`in``lookup_type`吗？

7 个答案: