ModelMultipleChoiceFilter - wrong field format in request url

Hi,

I am using django-filters ModelMultipleChoiceFilter. I am running into a problem where values from the input field are not correctly converted to the django-filters format, i.e. filter_field=value_1&filter_field=value_2&.... The value from the input field is treated as one value (none of the separators seem to work, the format of query params in request is like filter_field=value_1,value_2,...).

The filter that I have looks something like this:

from django_filters import rest_framework as filters
from django.contrib.auth.models import User

class TeamFilterSet(filters.FilterSet):
    members = filters.ModelMultipleChoiceFilter(
        label=_('Filter by member IDs'),
        field_name='members',
        queryset=User.objects.all(),
    )

Is it possible to obtain the expected format in the request url or do I have to override the actual filter to get the proper values from the request?

[lderlecki]

Yes, this solution works! Thank you so much for your help!

[tfranzel]

ahh now i get it! the schema you receive comes from django-filter itself. they generate a filter schema themselves but that is pretty much useless almost all of the time because they don’t have the introspection tooling we have.

our extension does not active as it is a different class. we can match subclasses but it is safer not to by default when you do custom stuff.

simply define a new extension based on the existing one. this should do it for you

from drf_spectacular.contrib.django_filters import DjangoFilterExtension

class CustomDjangoFilterExtension(DjangoFilterExtension):
   target_class = 'django_filters.rest_framework.DjangoFilterBackend'
   priority = 1
   match_subclasses = True

edit fyi: https://drf-spectacular.readthedocs.io/en/latest/faq.html#where-should-i-put-my-extensions-my-extensions-are-not-detected