ruby-on-rails – Rails Paperclip多态样式

# models/Asset.rb
class Asset < ActiveRecord::Base
  # Asset has to exist as a model in order to provide inheritance
  # It can't just be a table in the db like in HABTM. 
end

# models/Audio.rb
class Audio < Asset # !note inheritance from Asset rather than AR!
  # I only ever need the original file
  has_attached_file :file
end

# models/Video.rb
class Video < Asset
  has_attached_file :file,:styles => {
      :thumbnail => '180x180',:ipod => ['320x480',:mp4]
      },:processors => "video_thumbnail"
end

# models/Image.rb
class Image < Asset
  has_attached_file :file,:styles => {
      :medium => "300x300>",:small => "150x150>",:thumb => "40x40>",:bigthumb => "60x60>"
    }
end

它们都进入Rails as：file,但控制器(A / V / I)知道保存到正确的模型.请记住,任何媒体形式的所有属性都需要包含在资产中：如果视频不需要字幕而图像不需要,那么视频的字幕属性将为零.它不会抱怨.

如果连接到STI模型,协会也将正常工作.用户has_many：视频的运行方式与您现在使用的相同,只是确保您不要尝试直接保存到资产.

# controllers/images_controller.rb
  def create
    # params[:image][:file] ~= Image has_attached_file :file
    @upload = current_user.images.build(params[:image]) 
    # ...
  end

最后,既然你有资产模型,你仍然可以直接从中读取,例如你想要一份20个最近资产的清单.此外,该示例不限于分离媒体类型,它也可以用于不同类型的相同事物：Avatar<资产,图库<资产等.