Rails - Sep 2008 - 1 comment system for multiple models

Hi all,

I have a commenting system I use on different models (posts, reports,
events) meaning that I have some difficulties using depend => destroy
and counter cache.

I now use a sub_id in my comment indicating whether the comment
belongs to a post, event or report eg:
Events table
id | owner_id | category_id | text
0       1          post       ...
1       1          event      ...
2       2          report     ...
3       2          post       ...

Where the owner_id is the id own the post, event or report.


This approach makes it hard to use either counter cache or depend =>
destroy since it will only look at the owner_id. If a user deletes
post 1 it will also delete the comments of both event 1 and report 1.

Someone has a better approach to using 1 comment system for multiple
models or can I overwrite counter cache and depend destoy to make use
of scoping?

All help is greatly appreciated.

Stijn




--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

What you want to use here are polymorphic associations.
They work mostly like what you have done, using two
columns, one for the id, the other for the type.
commentable_id
commentable_type
in your case.

Then you could define associations like
has_many :comments, :as => :commentable, :dependent => :destroy

and Rails would be able to handle al the sub tasks as
it does with common associations.

read the details here:
http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html
since it''s a bit too complex to explain it here

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---