#387 Cache Digests

Oct 20, 2012 | 7 minutes | Performance, Caching, Rails 4.0

The cache_digests gem (also included in Rails 4) will automatically add a digest to the fragment cache key based on the template. If a template changes the cache will auto-expire. But watch out for the gotchas!

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Episode 90: Fragment Caching (revised)

          Gemfile
        
gem 'cache_digests'

          models/task.rb
        
belongs_to :project, touch: true

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

          projects/_project.html.erb
        
<% cache project do %>
  <h2><%= link_to project.name, edit_project_path(project) %></h2>
  <ul><%= render partial: 'tasks/task', collection: project.incomplete_tasks %></ul>
<% end %>

          tasks/_task.html.erb
        
<% cache task do %>
  <li>
    <%= task.name %>
    <%= link_to "rename", edit_task_path(task) %>
  </li>
<% end %>