a little json encoder for use with GAE models

gaejson.py

from django.utils import simplejson as json
from google.appengine.ext import db

class GaeEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, db.Model):
            output = {}
            for key, prop in obj.properties().iteritems():
                if isinstance(prop, db.ListProperty) and prop.item_type == db.Key:
                    output[key] = [ db.get(k) for k in getattr(obj, key) ]
                else:
                    output[key] = getattr(obj, key)
            return output
        elif isinstance(obj, db.Query):
            return [ self.default(k) for k in obj ]
        return super(self, GaeEncoder).default(obj)