issue with query filter on django.JSONField

[amirhoseinbidar]

django-filter can not filter on jsonField with NumberFilter

my situation is something like below desctiption

I have a model like this

class Product(model.Model):
    name = models.CharField(max_length=250)
    ....
    extra_data = models.JSONField(default=dict, null=True, blank=True)

assume some of extra_data always have something like { "size": 200 }

my filter is

class ProductFilter(FilterSet):
    extra_size = filters.NumberFilter(field_name="extra_data", lookup_expr="size")
    ....

when i call my end point (EXAMPLE: http://localhost:8001/api/products/rent/product/?extra_size=200) this error will raise

--some text--
.....
TypeError: Object of type Decimal is not JSON serializable

after some debug I found out this error is because NumberFilter turn income numbers to Decimal objects and jsonfield just
can not handle Decimal object

I am not sure this issue is yours or for JSONField but I will report same bug for JSONField

[amirhoseinbidar]

I found out this problem can solve with this way

from django_filters import filters
from django import forms


class IntegerFilter(filters.NumberFilter):
    field_class = forms.IntegerField


class FloatFilter(filters.NumberFilter):
    field_class = forms.FloatField


class IntegerRangeField(filters.RangeField):
    def __init__(self, fields=None, *args, **kwargs):
        if fields is None:
            fields = (
                forms.IntegerField(),
                forms.IntegerField())
        super().__init__(fields, *args, **kwargs)


class FloatRangeField(filters.RangeField):
    def __init__(self, fields=None, *args, **kwargs):
        if fields is None:
            fields = (
                forms.FloatField(),
                forms.FloatField())
        super().__init__(fields, *args, **kwargs)


class IntegerRangeFilter(filters.RangeFilter):
    field_class = IntegerRangeField


class FloatRangeFilter(filters.RangeFilter):
    field_class = FloatRangeField

and inside my filter

class ProductFilter(FilterSet):
    extra_size = filters.IntegerFilter(field_name="extra_data", lookup_expr="size")

I thing it is good idea add this solution to your document

[carltongibson]

Thanks @amirhoseinbidar — I’m going to mark this a duplicate of #1298