I'm wondering if it is possible to add a field to a Model class with a
mixin.
Here's my hypothetical problem: let's say that I am designing Blog
software -- I know, I know, what an innovation! -- that features Posts
and Comments.
class Post(db.Model):
title = db.StringProperty(required=True)
body = db.TextProperty(required=True)
added = db.DateProperty(auto_add_now=True)
class Comment(db.Model):
author = db.UserProperty()
body = db.TextProperty()
added = db.DateProperty()
edited = db.DateProperty()
I would like Post to have a counter of the number of comments that it
has, so I could change my definition of Post to this:
class Post(db.Model):
title = db.StringProperty(required=True)
body = db.TextProperty(required=True)
added = db.DateProperty(auto_add_now=True)
comments_counter = db.IntegerProperty(required=True, defualt=0)
However, what I would really to do is have a mixin class called
Commentable that will add a variety of useful methods to the class
that mixes it in. It'd be super cool to be able to have
comments_counter added in by it:
class Commentable:
comments_counter = db.IntegerProperty(required=True, default=0)
# Various method definitions excluded for brevity...
class Post(db.Model, Commentable):
title = db.StringProperty(required=True)
body = db.TextProperty(required=True)
added = db.DateProperty(auto_add_now=True)
# comments_counter = db.IntegerProperty(required=True, defualt=0)
# Now, comments_counter is included by Commentable mixin
I gave something like this a try last night, and it didn't seem to
work, so I figured that I'd ask before going too-deeply down a rabbit
hole.
If this won't work, I think that it'd be super cool. It would enable
a wide range of work-and-time saving plugins, such as in the Ruby on
Rails ecosystem.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Google App Engine" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/google-appengine?hl=en
-~----------~----~----~----~------~----~------~--~---
