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POCollections using has_many, :through relationships
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copied!<p>I want the current user to read and purchase postings in clubs in which he is a member. I would love to do something like the following, but nothing I've read or tried has clicked yet. I will be using many nesting collections of this type, I'm stuck!<br /><br /> <strong>Models</strong></p> <pre><code> class User < ActiveRecord::Base has_many :memberships has_many :clubs, :through => :memberships has_many :products class Membership < ActiveRecord::Base belongs_to :user belongs_to :club class Club < ActiveRecord::Base has_many :memberships has_many :users, :through => :memberships has_many :events class Event < ActiveRecord::Base belongs_to :club class Product < ActiveRecord::Base belongs_to :user has_many :posts class Post < ActiveRecord::Base belongs_to :product belongs_to :event </code></pre> <p><strong>Posts Controller</strong></p> <pre><code>def index @user = current_user @posts_in_my_clubs = @user.memberships.collect { |a| a.products.posts} </code></pre> <p><strong>posts/index.html.erb</strong></p> <pre><code>@posts_in_my_clubs do |post| </code></pre> <p>Gives me the error:</p> <blockquote> <p>undefined method `memberships' for nil:NilClass</p> </blockquote> <p>To which I am not surprised. Additionally I want to be able to select only the posts that will be only at a certain event, etc. </p> <p>A summary of the models: Clubs have many Events & Users. Users have many Products to which they can Post a quantity to sell at different Event dates. Only Users who are members of a Club can post or view posts in a Club. </p> <p>Instead of repeating data in the models, I have made associations, which seem to make the data inaccessible to creating collections in ActiveRecord. I've found in my research <a href="http://ar.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html" rel="nofollow">Association Join Models</a>, and <a href="http://metautonomo.us/projects/metawhere/#associations" rel="nofollow">Intelligent association mapping</a> with metawhere. These links make me feel like I'm getting close.</p> <p>Edit</p> <p>I'm signed in and can access all of the data I need as long as I'm not trying to do a collection like this. For instance I can check if I'm a member of the club by </p> <pre><code>def member?(club) return !!self.clubs.find(club) </code></pre> <p>I am a noob, so I must be missing something obvious here. Do I need to break up my collection into steps? i.e. collect user clubs, collect user clubs products, collect user clubs products posts... thanks</p> <p>Logger.info</p> <pre><code> @user = current_user logger.info @user logger.info 'super secret message' # @club_posts = @user.memberships.collect {|a| a.product.posts} </code></pre> <p>returns</p> <pre><code>#<User:0x5b202a0> super secret message </code></pre> <p>When I remove the comment, I get the nil error again, for 'product' now (progress!). I sure thought I was logged in before.. tho it was late</p>

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