Rails 缓存清扫器

Question

我正在尝试实现一个缓存清扫器，它会过滤特定的控制器操作。

class ProductsController < ActionController  
    caches_action :index  
    cache_sweeper :product_sweeper  

    def index 
        @products = Product.all 
    end 

    def update_some_state
      #... do some stuff which doesn't trigger a product save, but invalidates cache
    end
end 

清扫班：

class ProductSweeper < ActionController::Caching::Sweeper
    observe Product

    #expire fragment after model update
    def after_save
       expire_fragment('all_available_products')   
    end

    #expire different cache after controller method modifying state is called.
    def after_update_some_state
        expire_action(:controller => 'products', :action => 'index') 
    end
end

ActiveRecord 回调“after_save”可以正常工作，但控制器操作“after_update_some_state”的回调似乎永远不会被调用。

Answer 1

看起来我只是在尝试让控制器操作的回调正常工作时丢失了控制器名称。我的清扫器应该是：

class ProductSweeper < ActionController::Caching::Sweeper
    observe Product

    #expire fragment after model update
    def after_save
       expire_fragment('all_available_products')   
    end

    #expire different cache after controller method modifying state is called.
    def after_products_update_some_state
        expire_action(:controller => 'products', :action => 'index') 
    end

    #can also use before:
    def before_products_update_some_state
        #do something before. 
    end
end

Answer 2

我认为你的扫地机应该是这样的：

class ProductSweeper < ActionController::Caching::Sweeper
  observe Product

  def after_save(product)
     expire_cache(product)
  end

  def after_destroy(product)
    expire_cache(product)
  end

  private

  def expire_cache(product)
    expire_fragment('all_available_products')
    expire_page(:controller => 'products', :action => 'index')
  end 

after_index 不是回调，除非你定义它。

在控制器中，您应该指定应该触发清扫器的动作，这些动作应该是create, update, destroy，因此您的控制器声明应该如下所示：

class ProductsController < ActionController  
  caches_action :index  
  cache_sweeper :product_sweeper, :only => [:create, :update, :destroy]  

  def index 
    @products = Product.all 
  end 

  def create
    @product = Product.new(params[:product])

     if @product.save # triggers the sweeper.
       # do something
     else
       # do something else
     end
   end

  # update and stuff ...
end 

希望对你有帮助！