class AlbumUnprocess include Mongoid::Document field :image_id field :save_var, type: String field :upload_success, type: Boolean def save_var temp = YAML.load(self[:save_var]) temp[:tempfile] = File.open(temp[:tempfile]) ActionDispatch::Http::UploadedFile.new(temp) end def save_var=(value) temp = {:filename => value.original_filename, :type => value.content_type, :head => value.headers, :tempfile => value.tempfile.path} self[:save_var] = temp.to_yaml end end