has_many through additional attributes

Question

How do we set additional parameters in has_many through associations?

Thanks. Neelesh

Answer 1

Got the same problem here. Can't find any tutorials how to make it work on-the-fly in Rails 3. But you can still get what you want through the join model itself.

p = Post.new(:title => 'Post', :body => 'Lorem ipsum ...')
t = Tag.new(:title => 'Tag')

p.tags << t
p.save   # saves post, tag and also add record to posttags table, but additional attribute is NULL now
j = PostTag.find_by_post_id_and_tag_id(p,t)
j.user_id = params[:user_id]
j.save   # this finally saves additional attribute

Pretty ugly but this works from me.