Action and Fragment caching supported by Rails.

rails_cache

Action and Fragment caching supported by Rails.cache, working like caching in HTML templates:

_product.html.erb

<!-- @see https://devcenter.heroku.com/articles/caching-strategies#fragment-caching -->

<% cache(product) do %>
   <div><%= link_to product, product.name %>: <%= product.price%></div>
   <div><%= do_something_comlicated%></div>
<% end %>

index.html.erb

<!-- @see https://devcenter.heroku.com/articles/caching-strategies#fragment-caching -->

<%= render :partial => "product", :collection => @products %>
 
<% cache("top_products", :expires_in => 1.hour) do %>
  <div id="topSellingProducts">
    <% @recent_product = Product.order("units_sold DESC").limit(20) %>
    <%= render :partial => "product", :collection => @recent_products %>
  </div>
<% end %>

product.rb

# @see https://devcenter.heroku.com/articles/caching-strategies#low-level-caching

def Product.out_of_stock
  Rails.cache.fetch("out_of_stock_products", :expires_in => 5.minutes) do
    Product.all.joins(:inventory).conditions.where("inventory.quantity = 0")
  end
end
 
def competing_price
  Rails.cache.fetch("/product/#{id}-#{updated_at}/comp_price", :expires_in => 12.hours) do
    Competitor::API.find_price(id)
  end
end

products_controller.rb

# @see https://devcenter.heroku.com/articles/caching-strategies#action-caching

class ProductsController < ActionController
 
  before_filter :authenticate
  # @see http://guides.rubyonrails.org/caching_with_rails.html#activesupport-cache-ehcachestore
  caches_action :index, expires_in: 60.seconds, unless_exist: true
  # caches_action :index
  caches_action :show, :layout => false
 
  def index
    @products = Product.all
  end
 
  def show
    @product = Product.find(params[:id])
  end
 
  def create
    expire_action :action => :index
  end
 
end