在DRF中删除与PrimaryKeyRelatedField的ManyToMany关系

from rest_framework import serializers

class UserSerializer(serializers.ModelSerializer):
    roles = serializers.PrimaryKeyRelatedField(many=True, queryset=Role.objects.all())

    class Meta:
        model = User
        fields = ['id', 'username', 'roles']

from rest_framework import viewsets

class UserViewSet(viewsets.ModelViewSet):
    queryset = User.objects.all()
    serializer_class = UserSerializer

    def update(self, request, *args, **kwargs):
        instance = self.get_object()
        roles = request.data.get('roles', [])
        instance.roles.set(roles)  # 更新角色列表
        instance.save()
        return super().update(request, *args, **kwargs)