SQLAlchemy models for resources

todo_models.py

class ToDo(BaseObject):
    __tablename__ = 'todo'
    id = Column(Integer, primary_key=True)
    title = Column(Text)
    acl = Column(ArrayType)
    default_acl = [
        (Allow, Everyone, 'view'),
        (Allow, 'group:editors', 'edit')
    ]
    owner_id = Column(Integer, ForeignKey('users.id'))
    owner = relationship('User')

    def __acl__(self=None):
        return getattr(self, 'acl', None) or ToDo.default_acl

    @classmethod
    def by_id(cls, todo_id):
        # Do an int() just in case '1' was passed in
        return Session.query(cls).filter_by(id=int(todo_id)).first()

    @classmethod
    def list(cls):
        return Session.query(cls).order_by(cls.title)


def todo_factory(request):
    todo_id = request.matchdict.get('id')
    if todo_id is None:
        # Return the class
        return ToDo
    todo = ToDo.by_id(int(todo_id))
    if not todo:
        raise HTTPNotFound()
    return todo