recursive model_to_dict

utils.py

from django.forms.models import model_to_dict as fmodel_to_dict
from django.db.models.related import RelatedObject


def remove_baseattr_name(prefix):
    def inner(value):
        return value[len(prefix)+1:]

    return inner


def model_to_dict(instance, fields=[], exclude=[]):
    """
    example use:
    model_to_dict(mymodel, fields=[], exclude=["related.field.name"])
    """
    basemodel = fmodel_to_dict(instance, fields, exclude)
    # get all foreign keys.
    for fname, type_ in instance._meta._name_map.items():
        if fname not in exclude:
            if type(type_[0]) is RelatedObject:
                basemodel[fname] = []
                for relobj in getattr(instance, fname).all():
                    related_serialize = model_to_dict(
                        relobj,
                        map(remove_baseattr_name(fname), fields),
                        map(remove_baseattr_name(fname), exclude)
                    )
                    del related_serialize[type_[0].field.name]
                    del related_serialize[relobj._meta.pk.name]

                    if hasattr(relobj, '_dump'):
                        related_serialize = relobj._dump(related_serialize)

                    basemodel[fname].append(related_serialize)

    return basemodel