Question

I have a many to many relationship between two models, Order and Product. There is a joining table called Lines so that users can add quantities to the products they’d like to order.

I have products nested within orders so my routes look like the following:

  resources :orders do
    resources :products, :controller => "products"    
  end
end

I’ve able to successfully go to the index (orders/id/products) if my index.html.erb is just a placeholder, however when trying to display data I’m having issues.

My Products table that is erroring out (on the <% @products.each… line) looks like the following:

<table>
  <tr>
    <th>URL</th>
    <th></th>
    <th></th>
    <th></th>
  </tr>

<% @products.each do |product| %>
  <tr>
    <td><%= product.url %></td>
    <td><%= link_to 'Show', product %></td>
    <td><%= link_to 'Edit', edit_order_products_path(product) %></td>
    <td><%= link_to 'Destroy', order, :confirm => 'Are you sure?', :method => :delete %></td>
  </tr>
<% end %>

My index method looks like the following:

  def index
    @order = Order.find(params[:order_id])
    @products = Product.all    


    respond_to do |format|
      format.html # index.html.erb
      format.xml  { render :xml => @products }
    end
  end

The error is stating my @products object is nil; however, in the console Product.all returns 4 items.

I’m a newb and this is my first time references nested resources, is it possible I’m simply trying to call it incorrectly using the instance variable @products?

Thanks

Answer 1

1) Do you have any products in your database? It’s good idea to check if you have any using: @products.present?

<% if @products.present? %>
  <% @products.each do |product| %>
   <tr>
    <td><%= product.url %></td>
    <td><%= link_to 'Show', product %></td>
    <td><%= link_to 'Edit', edit_order_products_path(product) %></td>
    <td><%= link_to 'Destroy', order, :confirm => 'Are you sure?', :method => :delete %></td>
   </tr>
 <% end %>
<% else %>
 <tr>
   <td colspan=4>You don't have any products yet.</td>
 </tr>
<% end %>

2) I suppose you want to show only products from this order. If you do, then you should write:

@products = @order.products

instead of

@products = Product.all