BIG mistake in Field.clean method

[liminspace]

There is code:

if not value and self.default != NOT_PROVIDED:
    if callable(self.default):
        return self.default()
    return self.default

WTF guys? Why if not value you will set default? o_O
If self.default is 1 and value is 0 it is OK! Why you going to change value if it is NOT BOOL(VALUE)?
I have problem with this strange logic all time.
How you can use this library with this mistake?
Why nobody can't fix this stupid mistake???

[liminspace]

My fast solution (with other solutions):

from import_export import resources, fields, widgets
from django.contrib.contenttypes.models import ContentType

class IEField(fields.Field):
    def clean(self, data):
        try:
            value = data[self.column_name]
        except KeyError:
            raise KeyError("Column '%s' not found in dataset. Available "
                           "columns are: %s" % (self.column_name,
                                                list(data.keys())))

        try:
            value = self.widget.clean(value)
        except ValueError as e:
            raise ValueError("Column '%s': %s" % (self.column_name, e))

        return value


class IEModelResource(resources.ModelResource):
    @classmethod
    def field_from_django_field(self, field_name, django_field, readonly):
        FieldWidget = self.widget_from_django_field(django_field)
        widget_kwargs = self.widget_kwargs_for_field(field_name)
        field = IEField(
            attribute=field_name,
            column_name=field_name,
            widget=FieldWidget(**widget_kwargs),
            readonly=readonly,
            default=django_field.default,
        )
        return field


class FloatNullWidget(widgets.NumberWidget):
    def clean(self, value):
        if self.is_empty(value) or value in ('None', ''):
            return None
        return float(str(value).replace(',', '.'))


class ContentTypeWidget(widgets.Widget):
    def clean(self, value):
        return ContentType.objects.get_by_natural_key(*value.split('.'))

    def render(self, value):
        return '{}.{}'.format(value.app_label, value.model)

Use IEField instead fields.Field
Use IEModelResource instead resources.ModelResource
Use ContentTypeWidget for content type field:

class MyResource(IEModelResource):
    content_type = IEField(attribute='content_type', widget=ContentTypeWidget())

    class Meta:
        model = MyModel
        fields = ('id', 'content_type', 'object_id', 'lang', 'text')
        export_order = fields
        skip_unchanged = True
        report_skipped = False
        use_transactions = True

    def get_queryset(self):
        qs = super(MyResource, self).get_queryset()
        return qs.select_related('content_type').order_by('pk')

Use FloatNullWidget for float field with null=True:

lat = IEField(attribute='lat', widget=FloatNullWidget())

[bmihelac]

Hey @liminspace, I think that your language is inappropriate so please stop using it. We are committed to providing a friendly, safe and welcoming environment for all.

Regarding this issue, there is some discussion in #364

I would gladly accept pull request that fixes this issue.