Rails-based lazy loading, server push with Juggernaut.

lazy_loading.rb

module LazyLoadHelper
   def lazy_load(&block)
      content_id = ActiveSupport::SecureRandom.hex

      EM.add_timer 2 do
        javascript = %{$('##{content_id}').replaceWith('#{
          escape_javascript(capture(&block))
        }')}

        Juggernaut.send_to_channels(javascript, [content_id])
      end
      @juggernaut_channels ||= []
      @juggernaut_channels << content_id
      content_tag('span', image_tag('spinner.gif'), 'id' => content_id)
   end
end


#In the view:

<% lazy_load do %>
  <div> <%= Time.now %> </div>
<% end %>

<%= juggernaut :channels => @juggernaut_channels %>