>这个应用程序是我的学习应用程序基于迈克尔哈特尔出色的铁路教程.
> App在开发中运行顺畅,测试套件全是绿色
>部署到Heroku时,我立即收到以下错误：“应用程序错误.应用程序出错,无法提供您的页面”
>问题在升级到Rails4后开始(但我知道问题不在于Rails4本身,因为例如git：//github.com/railstutorial/sample_app_rails_4.git可以很好地部署到Heroku)
>我知道你会问“你在Heroku上迁移了数据库吗？”.我做到了.我甚至运行了pg：reset然后再次在Heroku上运行db：migrate以防万一.他们似乎运行正常.

Heroku日志也不提供任何信息(至少,我看不到任何有用的信息)

2013-05-25T22:11:26.070468+00:00 heroku[web.1]: Process exited with
status 0
2013-05-25T22:11:26.083572+00:00 heroku[web.1]: State changed from
starting to crashed
2013-05-25T22:13:09.372294+00:00 heroku[run.4121]: State changed from up
to complete
2013-05-25T22:13:09.357146+00:00 heroku[run.4121]: Process exited with
status 1
2013-05-25T22:13:50.829887+00:00 heroku[router]: at=error code=H10
desc="App crashed" method=GET path=/ host=devsampleapp.herokuapp.com
fwd="93.172.16.63" dyno= connect= service= status=503 bytes=

rails控制台也没出现：

2013-05-26T06:41:34.942569+00:00 heroku[api]: Starting process with command `bin/rails console` by assafshomer@gmail.com
2013-05-26T06:41:38.312107+00:00 heroku[run.5325]: Awaiting client
2013-05-26T06:41:38.339816+00:00 heroku[run.5325]: Starting process with command `bin/rails console`
2013-05-26T06:41:39.112396+00:00 heroku[run.5325]: Client connection closed. Sending SIGHUP to all processes
2013-05-26T06:41:40.329832+00:00 heroku[run.5325]: Process exited with status 0
2013-05-26T06:41:40.357047+00:00 heroku[run.5325]: State changed from starting to complete

我提交了一张Heroku的支持票,但这只会在最早的星期二进行,而且我很想让这个“升级到rails4”已经工作了,所以,任何帮助解决这个谜团的人都会非常感激.

很明显,重现的最好方法是克隆repo并部署到heroku