重构:如何在Rails更新操作中有效地呈现json

Question

我如何重构这段代码，这样我就不会在使用相同的基本格式时一遍又一遍地重复json对象?我对Ruby on Rails还是有点不舒服，所以我不确定最好的方法是什么。

  # PUT /users/:user_id/profile/:id
  def update
    if request.xhr?
      profile = current_user.profile
      if params[:profile].blank?
        render :json => { :error => "There was no profile data passed in so your profile could not be saved." }, 
               :status => :unprocessable_entity
      else
        if profile.update_attributes(params[:profile])
          render :json => { :interests => 
                              simple_format(h(profile.interests), :class => "pbs tl"),
                            :favorite_music =>
                              simple_format(h(profile.favorite_music), :class => "pbs tl"),
                            :favorite_movies =>
                              simple_format(h(profile.favorite_movies), :class => "pbs tl"),
                            :favorite_books =>
                              simple_format(h(profile.favorite_books), :class => "pbs tl"),
                            :favorite_foods =>
                              simple_format(h(profile.favorite_foods), :class => "pbs tl") },
                 :status => :ok
        else
          render :json => { :error => get_errors_for_class(profile).to_sentence }, 
                 :status => :unprocessable_entity
        end
      end
    end
  end

---

Update:我稍微修改了原始答案，它适用于我。下面是我的修改:

  # within profile.rb
  # create a hash of profile attributes
  def html_to_hash
    %w{interests favorite_music favorite_books favorite_foods}.inject({}) do |hash, property|
      hash[property] = simple_format(h(self.send(property)), :class => 'pbs tl')
      hash
    end    
  end

Answer 1

将这个庞大哈希中的数据设为Profile的方法

class Profile
  def to_hash
    [:interests, :favorite_music, :favorite_books, :favorite_foods].inject({}) do |h, prop|
      h[prop] = simple_format(h(self.send(:prop)), :class => 'pbs tl')
      h
    end
  end
end

然后

# PUT /users/:user_id/profile/:id
  def update
    if request.xhr?
      profile = current_user.profile
      if params[:profile].blank?
        render :json => { :error => "There was no profile data passed in so your profile could not be saved." }, 
               :status => :unprocessable_entity
      else
        if profile.update_attributes(params[:profile])
          render :json => profile.to_hash,
                 :status => :ok
        else
          render :json => { :error => get_errors_for_class(profile).to_sentence }, 
                 :status => :unprocessable_entity
        end
      end
    end
  end

Answer 2

你可以在你的Profile类上创建一个as_json方法，它返回相同的哈希值，然后只做render :json => profile。另一种替代方法是插入ActiveModel::Serializers并告诉它您想要序列化哪些属性以及如何序列化。