我的Thorfile：

class Db < Thor
 
  desc "show_Version","some description ..."
  def show_version # <= needs a database connection
    puts ActiveRecord::Migrator.current_version
  end
 
  private
 
  def connect_to_database # <= call this always when a task from this file is executed
    # connect here to database
  end
 
end

我可以在每个任务中编写“connect_to_database”方法,但这似乎不是很干.