Rails 中的缓存

需要缓存的

• 全静态页面
• 数据库密集访问 但又几乎无变化的动态页面
• 动态页面的片段

 

 

开发环境开启缓存

/config/environments/development.rb

 

config.action_controller.perform_caching = true  

  

 

 

如果动态页面不经常更改，可以使用页面级的缓存。Page Cache AND Fragment Cache

页面和分段缓存二者均在控制器级别发生。

 

清单 1. 页面缓存 Page Cache

 

class FooController < ApplicationController
  caches_page :privacy_policy, :user_agreement 
end

 

 

清单 2. 分段缓存 Fragment Cache 【不涉及request 的动态params】

 

<% cache 'gifts_index' do %>
    <h3>
      Here, you can make the world a better place with a single gift. Donation gifts 
      are also a wonderful way to honor friends and family. Just imagine what we
      can achieve together.
    </h3>
    <h2 class="lightBlue"><%= @event_title %></h2>
    <div id="homefeatureitems">
        <% for gift in @event_gifts %>
          <%= render :partial => 'gifts/listable', :locals => { :gift => gift } %>
        <% end %>
    </div>
    ...
<% end %>

  

 

清单 3. 分段缓存 Fragment Cache 【URL标识】

 

<% cache @cause.permalink(params[:id]) do %>

  

 

页面缓存优势是速度快。缺点是伪静态，不走后台。

实际上，很多action都有before filter。如果要先身份认证才能访问页面，页面缓存不行。

动作缓存让你能够利用控制器上的任何过滤器。

 

清单 4. 动作缓存

class FoooController < ApplicationController
      caches_action :secret_page, :secret_list 
end

 

 

 

最后 cache expire

• 缓存到期失效
• 数据更新

 

清单 5. 基于时间的缓存到期

# -*- encoding : utf-8 -*-
class HomeController < ApplicationController
  layout "home_manage"
  skip_before_filter :verify_authenticity_token, :only => [:upload_img]

  caches_action :index, :expires_in => 1.days
  # before_filter :get_vote
end

 

清单 6. 使缓存失效

# -*- encoding : utf-8 -*-
class HomeSweeper < ActionController::Caching::Sweeper
  observe HomeRecommend, HomeKv, HomeBanner, FitLiteral, FitImage, Question, OwnerEnter,
          HomeImageLibPhoto, HomeDesignShow, HomeLifeVideo, IBanner

  def after_create(model)
    # expire_action("/index")
    expire_index
  end

  def after_update(model)
    # expire_action("/index")
    expire_index
  end

  def after_destroy(model)
    # expire_action("/index")
    expire_index
  end

  def expire_index
    cache_key = "views/#{request.host_with_port}/index"
    Rails.cache.delete(cache_key)
  end
end

 

 

参考链接：

https://www.ibm.com/developerworks/cn/web/wa-rails1/

评论

1 楼 FZtree 2014-10-03  

ActionController::Base.expire_page(app.url_for(:controller => 'foo',
                                               :action => 'bar',
                                              nly_path => true))