Problem using build with has_many :through relationship

Hello all,
I’m having problems creating a new record with has_many :through
My application is quite complicated so I’ll try to explain it as easy as
I can.

I have a many to many relationship with Projects, IRBs and Reviews.
Where reviews is the joined model.

In the new project view, I have a link (add IRB). This will add an a
list of IRBs to the new project form.
I have visited a Railscast(#73-75) similar to this.
The difference is I need to search for an IRB# first.
Therefore when use the link it will open a jQuery UI dialog box. Within
the dialog, I have a search bar for ‘irbs’.
When a search is implemented, the results appear in the dialog box. Each
result has a 'irb#, title and a link “add IRB”
This link will add/create the association in the Reviews model.

I have setup everything up similar to a Railscast (163. Self-Referential
Association) but when I click the ‘Add IRB’, I get a “undefined method
`reviews’ for #Array:0x10322cbb8” error.

My project, irb and review models.

  • project model -
    class Project < ActiveRecord::Base
    has_many :reviews
    has_many :irbs, :through => :reviews

-irb model -
class Irb < ActiveRecord::Base


has_many :reviews
has_many :projects, :through => :reviews

  • review model -
    class Review < ActiveRecord::Base
    belongs_to :irb # foreign key - irb_id
    belongs_to :project # foreign key - project_id

  • reviews_controller -
    class ReviewsController < ApplicationController
    def create
    @review = :irb_id => params[:id] )
    flash[:notice] = “IRB added.”
    redirect_to new_project_path
    flash[:error] = “Unable to add IRB.”
    redirect_to new_project_path

    def destroy
    @review =[:id])
    flash[:notice] = “IRB Removed.”
    redirect_to new_project_path


Here’s the partial to which the “Add IRB” link is.

  • _searchresults.html.erb -
    <% content_for :head do %>
    <%= stylesheet_link_tag ‘dialog’ %>
    <% end %>
<% @irbs.each do |irb| %> <% end %>
IRB Search Results
IRB ID Title PI Full Name Actions
<%=h irb.IRB %> <%=h truncate(irb.Title, :length => 30) %> <%=h irb.PI_Full_Name %> <%= link_to 'Add IRB', reviews_path, :id =>, :method => :post %>
<%= will_paginate @irbs %>

Thank you for any advice or help with this.


On Jan 8, 3:48Â pm, John M. [email protected] wrote:

 def create
  @review = :irb_id => params[:id] )

this and

 def destroy
  @review =[:id])

this look weird - Project does not have a reviews method - instances
of it do. Especially in the first case you want to be getting an
appropriate instance of project first and then do on it