Как делают рубин на направляющих много атрибуты параметра *действительно* работа (datetime_select)

Вот что я в итоге придумал. Если у кого-то есть комментарии, дайте мне знать. Я бы хотел получить обратную связь.

  validate :datetime_format_and_existence_is_valid  
  before_save :merge_and_set_datetime   

  # virtual attributes for date and time allow strings
  # representing date and time respectively to be sent
  # back to the model where they are merged and parsed
  # into a datetime object in activerecord
  def date
    if (self.datetime) then self.datetime.strftime "%Y-%m-%d"
    else @date ||= (Time.now + 2.days).strftime "%Y-%m-%d" #default
    end
  end
  def date=(date_string)
    @date = date_string.strip
  end
  def time
    if(self.datetime) then self.datetime.strftime "%l:%M %p"
    else @time ||= "7:00 PM" #default
    end
  end
  def time=(time_string)
    @time = time_string.strip
  end

  # if parsing of the merged date and time strings is
  # unsuccessful, add an error to the queue and fail
  # validation with a message
  def datetime_format_and_existence_is_valid    
    errors.add(:date, 'must be in YYYY-MM-DD format') unless
      (@date =~ /\d{4}-\d\d-\d\d/) # check the date's format
    errors.add(:time, 'must be in HH:MM format') unless # check the time's format
      (@time =~ /^((0?[1-9]|1[012])(:[0-5]\d){0,2}(\ [AaPp][Mm]))$|^(([01]\d|2[0-3])(:[0-5]\d){0,2})$/)
    # build the complete date + time string and parse
    @datetime_str = @date + " " + @time
    errors.add(:datetime, "doesn't exist") if 
      ((DateTime.parse(@datetime_str) rescue ArgumentError) == ArgumentError)
  end

  # callback method takes constituent strings for date and 
  # time, joins them and parses them into a datetime, then
  # writes this datetime to the object
  private
  def merge_and_set_datetime
    self.datetime = DateTime.parse(@datetime_str) if errors.empty?
  end