def comments(cls):
#: make the meta data of the subject class
arguments = dict(cls.__commentable__)
arguments['subject_class'] = cls
#: create a comment class
class_name = "%sComment" % cls.__name__
class_bases = (BaseComment,)
class_members = {'__commentable__': arguments}
comment_class = type(class_name, class_bases, class_members)
comment_class.__doc__ = "The comment of the %s." % class_name
#: assign the comment class to the subject class
setattr(cls, class_name, comment_class)
setattr(cls, "comment_class", comment_class)
#: create and return the relationship to the comment
return db.relationship(comment_class, lazy="dynamic",
backref=db.backref("subject", lazy="joined", uselist=False))
def owner(cls):
owner_class = cls.__commentable__['owner_class']
return db.relationship(owner_class, lazy="joined", uselist=False)
