Question

I have a player, game, shot, round and team model.
When creating a shot, it belongs_to a all of those models. (This is because a team does not always have the same players, but reasons are unimportant.)
My game form accepts_nested_attributes for rounds and my rounds accepts_nested_attributes_for my shots (of which there are always 6 — 3 on each team)

To summarize, I have a nested form for game => rounds => shots and I need shots to have a round_id, player_id, team_id and game_id.

Should I use f.hidden_field, and if so, isn’t that dangerous? Even if I so how do I wire it so that the ids are in the right place?

I posted the views below, if anything else is needed let me know.

rounds/_form.html.erb

<% if @round.errors.any? %>
  <div class="error">
    <% @round.errors.full_messages.each do |msg| %>
      <%= msg %><br/>
    <% end %>
  </div>
<% end %>

<%= form_for @game do |f| %>
  <%= field_set_tag "#{@game.away.name} at #{@game.home.name}" do %>
    <table class="sortable">
      <thead>
        <tr>
          <th>Number</th>
          <th><%= @game.away_players[0].name %></th>
          <th><%= @game.away_players[1].name %></th>
          <th><%= @game.away_players[2].name %></th>
          <th><%= @game.home_players[0].name %></th>
          <th><%= @game.home_players[1].name %></th>
          <th><%= @game.home_players[2].name %></th>
          <th>Remove</th>
        </tr>
      </thead>
      <tbody>
        <%= f.fields_for :rounds do |round_form| %>
            <%= render 'round_fields', :f => round_form %>
        <% end -%>
      </tbody>
    </table>

    <p>
      <%= link_to_add_fields "Add Round", f, :rounds %>
    </p>

    <p>
      <%= f.submit %>
    </p>
  <% end %>
<% end %>

rounds/_round_fields.html.erb

<% 6.times { f.object.shots.build } if f.object.new_record? -%>
<tr>
  <td>
    <%= f.text_field :number, :size => 3 %>
  </td>

  <%= f.fields_for :shots do |shot_form| %>
    <%= render 'shot_fields', :f => shot_form %>
  <% end -%>

  <td>
    <%= f.check_box(:_destroy) %>
    <%= f.hidden_field :id %>
  </td>
</tr>

rounds/_shot_fields.html.erb

<td>
  <%= f.select :cup, [["Miss", 0], 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ["Suicide", 11]], :include_blank => "No Shot" %>
  <%# f.hidden_field :id %>
</td>

Answer 1

Maybe session vars that point to the required variables could work.