The filter result contains duplicate instance when filter by many_to_many field

[菠菜]

Exmple:

model:
class Tag(models.Model):
key = models.CharField(max_length=64, verbose_name=('键'))
value = models.CharField(max_length=64, verbose_name=('值'))

class Resource(models.Model):
name = models.CharField(max_length=64, verbose_name=('名称'))
tags = models.ManyToManyField('tag.Tag', related_name='resources', verbose_name=('标签'))

view:
class ResourceViewSet(ModelViewSet):
filter_fields = ('tags__key', 'tags__value')
queryset = Resource.objects.all()
serializer_class = ResourceSerializer
...

then create some tags and resources instances and make relation:
tag1 = Tag.objects.create(key='env', value='prod')
tag2 = Tag.objects.create(key='env', value='dev')
resource1 = Resource.objects.create(name='test')
resource.tags.add(*[tag1, tag2])

when i get 127.0.0.1/resource/resources/?tags__key=env
there will return tow obj:
[
{'id': 1, 'name': 'test'},
{'id': 1, 'name': 'test'}
]

version:
Django(3.2) + djangorestframework(3.12.4) + django-filter(21.1)

[Carlton Gibson]

You need to use distinct. See the docs: https://django-filter.readthedocs.io/en/latest/ref/filters.html?highlight=Distinct#distinct

[菠菜]

@carltongibson i think is not a friendly design that the distinct default value is True. if that i have to write the filterset if any model has m_2_m filed. if the default value is True, I only set filter_fields = ('tags__key', 'tags__value') in viewset.