retry_sample.rb

gistfile1.rb

  def perform(member_course_id, ls_db, retry_count=0)
    member_course = nil
    begin
      member_course = MemberCourse.find(member_course_id)
    rescue ActiveRecord::RecordNotFound => e
      if retry_count<3
        # Chances are that the job is enqueued before the transaction is
        # committed. #6511
        Resque.enqueue_at(30.seconds.from_now, self.class, member_course_id, ls_db, retry_count+1)
        return
      else
        # The member_course presumably is deleted. There is enough time waiting. So
        # Just ignore here.
        return
      end
    end

    Member.current_with_block(member_course.member) do
      begin
        # reloads member_course with ls_db
        member_course = MemberCourse.find(member_course_id)
      rescue ActiveRecord::RecordNotFound => e
        if retry_count<5
          # When memebr_course is not slonyed, that query gets erros but it's ignorable
          Resque.enqueue_at(15.minutes.from_now, self.class, member_course_id, ls_db, retry_count+1)
          return
        else
          raise e
        end
      end

      MemberCourse.transaction do
        member_course.lock!
        ActiveRecord::Base.transaction(ls_db) { perform_product(member_course) }
      end
    end
  end