Custom filter field for django-filter. Control two fields in a flexible manner.

filter.py

from django import forms
import django_filters
from django_filters.filters import Filter

CHOICES = (('AND', 'AND'), ('OR', 'OR'))

class NamePriceWidget(forms.MultiWidget):
    def __init__(self, attrs=None):
        widgets = (
            forms.TextInput(attrs=attrs),
            forms.Select(choices=CHOICES),
            forms.TextInput(attrs=attrs)
            )
        super(NamePriceWidget, self).__init__(widgets, attrs)

    def decompress(self, value):
        if value:
            return [value.start, value.operator, value.value.stop]
        return [None, None, None]

    def format_output(self, rendered_widgets):
        return '-'.join(rendered_widgets)


class NamePriceField(forms.MultiValueField):
    widget = NamePriceWidget

    def __init__(self, *args, **kwargs):
        fields = (
            forms.CharField(),
            forms.ChoiceField(choices=CHOICES),
            forms.DecimalField(),
        )
        super(NamePriceField, self).__init__(fields, *args, **kwargs)

    def compress(self, data_list):
        if data_list:
            return data_list
        return None

from django.db.models import Q

class NamePriceFilter(Filter):
    field_class = NamePriceField

    def filter(self, qs, value):
        if value:
            q_object = Q()

            try:
                operator = {'AND': Q.AND, 'OR': Q.OR}[value[1]]
            except KeyError:
                operator = Q.AND

            if value[0]:
                q_object = Q(name__startswith=value[0])
            if value[2]:
                q_object.add(Q(price__lte=value[2]), operator)
            return qs.filter(q_object)
        return qs