Ruby on Rails - Nested Loop (with Bootstrap)

Question

On Rails 4. I am trying to do a complex nested each loop with Bootstrap.

I have the models Users, Organizations, and Submissions. Submissions belongs to Users and Organizations--the current user creates new submissions and assigns it to an org (so, Submissions has the attributes :user_id and :organization_id).

I made a little image to illustrate what I am trying to do in the submissions index view:

Listing all of current user's submissions:

Basically, I need to find each organization/year the current user has assigned a submission to, then within that heading, group each current user's submission that belongs to the same org/year.

In order to get this formatting with Bootstrap, I need to have a .in_groups_of(3, false) statement (unless someone can tell me about something different) with a <div class="col-md-4"> layout. Here is my current code in the submission index view, which is not working as expected:

# find all submissions made by the current user, group by the
# submission's :contest_year and :organization_id attributes:

<% current_user.submissions.group([:contest_year, :organization_id]).each do |contest| %>
  <h2><%= contest.contest_year %>: <%= contest.organization.name %></h2>

# here is where it fails, it is finding all the submissions made by the user
# instead of just the submissions that belong under the
# specified contest_year/organization_id heading from above.
# I know I need 'contest' involved in here

  <% current_user.submissions.in_groups_of(3, false).each do |group| %>
    <div class="row">
    <% group.each do |submission| %>
      <div class="col-md-4">
        # submission information here
      </div>
    <% end %>
  </div><br/>
  <% end %>
<% end %>

This code returns something like this instead:

I hope all of this makes sense. So, how do I fix the nested loop so that it behaves like the first image. Thanks very much. Partial submission model/controller:

Submission.rb

  belongs_to :user
  belongs_to :organization

submissions_controller.rb

  def index
    @submissions = Submission.all
  end

Answer 1

You want to narrow the second call to current_user.submissions by organization. Instead of this:

current_user.submissions.in_groups_of(3, false).each do |group|

you want something like:

current_user.submissions.where(organization_id: contest.organization.id).in_groups_of(3, false).each do |group|

you might be able to do this instead:

current_user.submissions.where(organization: contest.organization).in_groups_of(3, false).each do |group|