Module: Padrino::Cache::Helpers::Fragment


Whereas page-level caching, described in the first section of this document, works by grabbing the entire output of a route, fragment caching gives the developer fine-grained control of what gets cached. This type of caching occurs at whatever level you choose.

Possible uses for fragment caching might include:

  • a 'feed' of some items on a page

  • output fetched (by proxy) from an API on a third-party site

  • parts of your page which are largely static/do not need re-rendering every request

  • any output which is expensive to render

Instance Method Summary

Methods included from Helpers::OutputHelpers

#block_is_template?, #capture_html, #concat_content, #concat_safe_content, #content_for, #content_for?, handlers, register, #yield_content

Instance Method Details

#cache(key, opts = {}, &block) ⇒ Object

This helper is used anywhere in your application you would like to associate a fragment to be cached. It can be used in within a route:


# Caching a fragment
class MyTweets < Padrino::Application
  enable :caching          # turns on caching mechanism

  controller '/tweets' do
    get :feed, :map => '/:username' do
      username = params[:username]

      @feed = cache( "feed_for_#{username}", :expires => 3 ) do
        @tweets = Tweet.all( :username => username )
        render 'partials/feedcontent'

      # Below outputs @feed somewhere in its markup.
      render 'feeds/show'


  • key (String) — cache key
  • opts (Hash) (defaults to: {}) — cache options, e.g :expires
  • Execution (Proc) — result to store in the cache