错误的错误``keep-alive'

Question

我经常在控制台中收到以下错误。我搜索的解决方案无法找到解决方案。

 Completed 200 OK in 201ms (Views: 197.1ms | ActiveRecord: 2.1ms)
    [2015-07-21 10:47:48] ERROR bad URI `keep-alive'.
    [2015-07-21 10:47:48] ERROR bad URI `keep-alive'.    
    [2015-07-21 10:47:48] ERROR bad URI `keep-alive'.

屏幕上的错误是：

Length Required
WEBrick::HTTPStatus::LengthRequired
WEBrick/1.3.1 (Ruby/2.2.1/2015-02-26) at localhost:3000