Serialize the @property methods in a Python class

Question

Is there a way to have any @property definitions passed through to a json serializer when serializing a Django model class?

example:

class FooBar(obj         


        

Answer 1

Things have changed a bit since 2010, so the answer of @user85461 seems to no longer be working with Django 1.8 and Python 3.4. This is an updated answer with what seems to work for me.

from django.core.serializers.base import Serializer as BaseSerializer
from django.core.serializers.python import Serializer as PythonSerializer
from django.core.serializers.json import Serializer as JsonSerializer
from django.utils import six

class ExtBaseSerializer(BaseSerializer):
    """ Abstract serializer class; everything is the same as Django's base except from the marked lines """
    def serialize(self, queryset, **options):
        self.options = options

        self.stream = options.pop('stream', six.StringIO())
        self.selected_fields = options.pop('fields', None)
        self.selected_props = options.pop('props', None)  # added this
        self.use_natural_keys = options.pop('use_natural_keys', False)
        self.use_natural_foreign_keys = options.pop('use_natural_foreign_keys', False)
        self.use_natural_primary_keys = options.pop('use_natural_primary_keys', False)

        self.start_serialization()
        self.first = True
        for obj in queryset:
            self.start_object(obj)
            concrete_model = obj._meta.concrete_model
            for field in concrete_model._meta.local_fields:
                if field.serialize:
                    if field.rel is None:
                        if self.selected_fields is None or field.attname in self.selected_fields:
                            self.handle_field(obj, field)
                    else:
                        if self.selected_fields is None or field.attname[:-3] in self.selected_fields:
                            self.handle_fk_field(obj, field)
            for field in concrete_model._meta.many_to_many:
                if field.serialize:
                    if self.selected_fields is None or field.attname in self.selected_fields:
                        self.handle_m2m_field(obj, field)
            # added this loop
            if self.selected_props:
                for field in self.selected_props:
                    self.handle_prop(obj, field)
            self.end_object(obj)
            if self.first:
                self.first = False
        self.end_serialization()
        return self.getvalue()

    # added this function
    def handle_prop(self, obj, field):
        self._current[field] = getattr(obj, field)


class ExtPythonSerializer(ExtBaseSerializer, PythonSerializer):
    pass


class ExtJsonSerializer(ExtPythonSerializer, JsonSerializer):
    pass

Usage:

>>> ExtJsonSerializer().serialize(MyModel.objects.all(), fields=['myfield', ...], props=['myprop', ...])