Rails 4-如何优化这段代码

Question

让我们说我有这样的代码：

class BooksController < ApplicationController

    def action1
        @books = ...
        @books = @books.someaction param1, param2
    end

    def action2
        @books = ...
        @books = @books.someaction param1, param2
    end

    def action3
        @books = ...
        @books = @books.someaction param1, param2
    end

    ...

    def action84
        @books = ...
        @books = @books.someaction param1, param2
    end

我经常在一个实例变量上运行这个操作。我想把它放在after_action过滤上，但是在呈现之后就会发生这种情况，所以这是没有好处的。

我怎么才能优化这个？

免责声明：，这是一个夸张的案例，而不是一个真实的案例。只是想把问题画得更生动些。我没有一个带有84操作的控制器。

Answer 1

您可以重写render，只是为了让特定的控制器在呈现之前始终完成您的任务。就像这样：

class BooksController < ApplicationController

  def action1
    @books = ...
  end

  def action2
    @books = ...
  end

  private

  def render(*args)
    if @books.present? && param1.present? && param2.present?
      @books = @books.someaction param1, param2
    end
    super
  end

end

Answer 2

只需在控制器中声明一个私有函数，并在操作中使用它：

class BooksController < ApplicationController
  def action1
    @books = ...
    foo
  end

  def action2
    @books = ...
    foo
  end

  def action3
    @books = ...
    foo
  end

  ...

  def action84
    @books = ...
    foo
  end

  private

  def foo
    @books = @books.someaction param1, param2
  end
end

Answer 3

我会看看曝光宝石。这样你就可以做如下的事情：

class BooksController < ApplicationController
    expose(:books) { books.someaction param1, param2 }

    def action1
        books = ...
    end

    def action2
        books = ...
    end

    def action3
        books = ...
    end

    ...

    def action84
        books = ...
    end
end