get missing values from defaults

[matejcik]

it would be nice to have something like this:

class User(Document):
    __collection__ = 'users'
    structure = {
        'name': unicode,
        'password': unicode,
        'description': unicode,
    }
    default_values = { 'description': u'i have not filled in a description' }
    use_transparent_defaults = True

u1 = fetch_user_with_description()
print u1.description # prints value from db
u2 = fetch_user_without_description()
print u2.description # takes value from default_values

this looks like a nice alternative to migration suppport for schemaless documents

[namlook]

This is the attended behavior. u2.description should return the filled value. What's wrong ?

[matejcik]

well, it doesn't. (in MongoKit 0.7.2 at least)

with the proposed enhancement, the following code would work:

from mongokit import Document
from mongokit import Connection as KitCon
from pymongo import Connection as MoCon

mc = MoCon()
kc = KitCon()

# create an "unexpected" record directly through PyMongo
mc.example.drop_collection('users')
mtable = mc.example.users
mtable.insert({'name':'hello','password':'world'})

@kc.register
class User(Document):
    __collection__ = 'users'
    structure = {
        'name': unicode,
        'password': unicode,
        'description': unicode,
    }
    default_values = { 'description': u'hello world' }

user = kc.example.User.find_one()
assert user['description'] == u'hello world'