rails4中使用cache_action, cache_page

TODO: 尚未测试。。。不知道是否需要配置 nginx .... 如果是那样的话速度估计会很快。

refer to: https://github.com/rails/actionpack-page_caching

cache_action一直是接口开发的神器，　但是在rails4 中用法略有不同。

1. in your Gemfile: 

 gem 'actionpack-page_caching'

2 in your controller: 

 class ItemsController < ApplicationController
   before_action :authenticate_user!, except: [:index, :show]
+  caches_page :index, :show

   def create
     @item = Item.new(item_params)
     @item.save
+    expire_page action: 'index'
+    expire_page action: 'show', id: @item.id
     redirect_to edit_item_path(@item), notice: '操作成功'
   end
 
   def update
     @item.update(item_params)
+    expire_page action: 'index'
+    expire_page action: 'show', id: @item.id
     redirect_to :back, notice: '操作成功'
   end
 
   def destroy
     @item.destroy
+    expire_page action: 'index'
+    expire_page action: 'show', id: @item.id
     redirect_to :back, notice: '操作成功'
   end

3. in your config file: 

# config/environments/production.rb 
 Rails.application.configure do
+  config.action_controller.page_cache_directory = "#{Rails.root.to_s}/public/deploy"
   config.action_mailer.default_url_options = { host: 'localhost', port: 3000 }