id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
35642	After Upgrading from Django 2.2.28 to Django 3.2.25, JSONField is returning data in string rather than dictionary/list	Bittu Ray		"{{{
class CustomPatchedJSONFormField(JSONFormField):

    def prepare_value(self, value):
        """"""
        Exclude returning None in case of {}, returning None makes the field empty when loaded
        from admin instead of returning {},
        which causes an error where empty dict was expected
        """"""
        if value != {} and value in self.empty_values:
            return None
        elif isinstance(value, str):
            return value
        else:
            return super(CustomPatchedJSONFormField, self).prepare_value(value)


class CustomJSONField(JSONField):
    """"""
    Overrides
    1. `formfield` to set our custom JSON field as `form_class`
    2. `from_db_value` to return a json from `str`
    """"""

    def formfield(self, **kwargs):
        defaults = {""form_class"": CustomPatchedJSONFormField}
        defaults.update(kwargs)
        return super(JSONField, self).formfield(**defaults)

    def from_db_value(self, value, expression, connection, context=None):
        
        if isinstance(value, str):
            try:
                return json.loads(value)
            except ValueError:
                return value

        return value
}}}


My Model 


{{{
class MyModel(models.Model):
      field1 = CustomJSONField(default=list)
}}}

when I am creating an object with dictionary as input, it's working perfectly fine, but when I am creating the object input as str or json.dumps, the output is also coming in string format rather than python dictionary or list format

for example


{{{
MyModel.objects.create(field1={""key1:""value""})
a = MyModel.objects.get(id=1)
print(a.field1)
# It prints - {""key1:""value""}
# It's working fine and I am getting the output in dictionary format
# but when I try this :

MyModel.objects.create(field1='{""key1:""value""}')
a = MyModel.objects.get(id=1)
print(a.field1)

# It prints - '{""key1:""value""}'
# The value of field1 is in string format rather than dictionary format

}}}

I am using Postgres as my database and it was working fine till Django 2.2.28




"	Bug	closed	contrib.postgres	3.2	Normal	invalid	jsonfield, django 3.2		Unreviewed	0	0	0	0	0	0