support skipping disabled related fields

[gbezyuk]

Let's say you have a model named Gallery, having One-to-Many relation to the second model, GalleryPhoto. Also, let's say GalleryPhoto has a boolean is_enabled field.

class Gallery(models.Model, ToDictMixin):
    pass

class GalleryPhoto(models.Model, ToDictMixin):
    gallery = models.ForeignKey(to=Gallery, related_name='photos')
    is_enabled = models.BooleanField(default=True, verbose_name=_('is enabled'))

There should be a way to skip photos with is_enabled=False.

[gbezyuk]

Current workaround for solving this issue is adding custom _to_dict_related_fields_strategy to the parent model:

class Gallery(models.Model, ToDictMixin):
    def _to_dict_related_fields_strategy(self, result):
        related_fields = [rf for rf in self._meta.get_fields() if rf.is_relation]
        for rf in related_fields:
            # TODO recursion using __ive_been_there_already to prevent stack overflow
            if rf.one_to_many:
                if not rf.related_name:
                    continue
                result[rf.related_name] = [
                    i.to_dict(inspect_related_objects=False) for i in getattr(self, rf.related_name).filter(is_enabled=True)]
            if rf.many_to_one or rf.one_to_one:
                related_object = getattr(self, rf.name)
                if hasattr(related_object, 'to_dict'):
                    result[rf.name] = related_object.to_dict(inspect_related_objects=False)
            if rf.many_to_many:
                print('many_to_many', rf.name, rf)

See filter(is_enabled=True) in the snippet.

[gbezyuk]

print('many_to_many', rf.name, rf) TODO remove =)