A custom encoder that helps serialize AppEngine's GeoPt and datetime objects

geodateencoder.py

import json
import datetime
from time import mktime
from google.appengine.ext import ndb


__author__ = 'oyewale'


class GeoDateEncoder(json.JSONEncoder):

    def default(self, obj):
        if isinstance(obj, datetime.datetime):
            return int(mktime(obj.timetuple()))
        elif isinstance(obj, ndb.GeoPt):
            return {'lat': obj.lat, 'lon': obj.lon}

        return json.JSONEncoder.default(self, obj)