#169 Dynamic Page Caching (revised)

Feb 11, 2012 | 7 minutes | Performance, Ajax, Caching

Page caching is great for speeding up the performance of a page, but what if it contains user-specific content? Learn how to load content in dynamically through JavaScript in this episode.

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Episode 89: Page Caching (revised)

          products_controller.rb
        
caches_page :index

def index
  @page_caching = true
  @products = Product.all
  sleep 2
end

          config/environments/development.rb
        
config.action_controller.perform_caching = true

          app/assets/javascripts/products.js.coffee
        
jQuery ->
  if $('#products').length
    $.getScript('/users/current')

          views/users/show.js.erb
        
<% if admin? %>
  $('.admin').show();
<% end %>
$('#container').prepend('<%=j render("layouts/dynamic_header") %>');

          views/layouts/application.html.erb
        
<%= csrf_meta_tag unless @page_caching %>
...
<%= render "layouts/dynamic_header" unless @page_caching %>

          views/layouts/_dynamic_header.html.erb
        
<div id="user_status">
  <% if current_user %>
    Logged in as <strong><%= current_user.name %></strong>.
    <%= link_to "Log out", logout_path %>
  <% else %>
    <%= link_to "Sign up", signup_path %> or
    <%= link_to "log in", login_path %>
  <% end %>
</div>

<% flash.each do |name, msg| %>
  <%= content_tag :div, msg, id: "flash_#{name}" %>
<% end %>

          app/assets/products.css.scss
        
#products .admin {
  display: none;
}