David Heinemeier Hansson也是一个相当奇妙的程序猿。然后这次本来想系统性学习下Ruby。可是发现细节好多。所以想换第二种学习方式，直接上手ROR。

关于这样的学习方式，我又去搜了一些经验回答。有一位前辈总结的非常好。

过了3本书。

1、《HeadFirst HTML AND CSS》

2、《The linux command line》

3、《Pro git》

从主要的前端。linux的总体和主要的shell。以及git工具。个人依据个人知识略过第一本，挑不懂的知识点看，后两本看得比較细致。

我发现会用git。并不知道快照原来是如此一回事，整个git的控制流程是与svn怎样的不同。第一次发现linux里面双击能够复制，鼠标中键能够直接粘贴。

后面再看的《Ruby on Rails tutorial》。第一章就是yak shaving。

自己配置ROR环境，然后正式部署到Heroku。然后问题就来了。Application Error和code=H10 desc="App crashed“问题。

Heroku本身能够看错误，点击view logs

watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQv/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />

at=error code=H10 desc="App crashed" method=GET path=/ host=xxx.herokuapp.com fwd= dyno= queue= wait= connect= service= status=503 bytes=

3、问题解决

依据这个并不能看出问题所在，继续查。

http://stackoverflow.com/questions/13496827/heroku-deployment-error-h10-app-crashed

跟第一个回答那样，输入heroku run rails console。能够排除一下故障。

2016-02-29T05:18:58.740439+00:00 app[web.1]: /app/vendor/bundle/ruby/2.2.0/gems/sass-rails-5.0.1/lib/sass/rails/helpers.rb:11:in `<top (required)>': uninitialized constant Sass::Script (NameError)

2016-02-29T05:18:58.740461+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/sass-rails-5.0.1/lib/sass/rails.rb:8:in `require'

2016-02-29T05:18:58.740463+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/sass-rails-5.0.1/lib/sass/rails.rb:8:in `<top (required)>'

2016-02-29T05:18:58.740463+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/sass-rails-5.0.1/lib/sass-rails.rb:1:in `require'

2016-02-29T05:18:58.740464+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/sass-rails-5.0.1/lib/sass-rails.rb:1:in `<top (required)>'

2016-02-29T05:18:58.740465+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler/runtime.rb:76:in `require'

2016-02-29T05:18:58.740466+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler/runtime.rb:76:in `block (2 levels) in require'

2016-02-29T05:18:58.740466+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler/runtime.rb:72:in `each'

2016-02-29T05:18:58.740469+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler/runtime.rb:72:in `block in require'

2016-02-29T05:18:58.740470+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler/runtime.rb:61:in `each'

2016-02-29T05:18:58.740470+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler/runtime.rb:61:in `require'

2016-02-29T05:18:58.740471+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/bundler-1.9.7/lib/bundler.rb:134:in `require'

2016-02-29T05:18:58.740472+00:00 app[web.1]:    from /app/config/application.rb:7:in `<top (required)>'

2016-02-29T05:18:58.740473+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:78:in `require'

2016-02-29T05:18:58.740473+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:78:in `block in server'

2016-02-29T05:18:58.740474+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `tap'

2016-02-29T05:18:58.740475+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:75:in `server'

2016-02-29T05:18:58.740475+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.0/lib/rails/commands/commands_tasks.rb:39:in `run_command!'

2016-02-29T05:18:58.740476+00:00 app[web.1]:    from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.0/lib/rails/commands.rb:17:in `<top (required)>'

2016-02-29T05:18:58.740477+00:00 app[web.1]:    from bin/rails:9:in `require'

2016-02-29T05:18:58.740477+00:00 app[web.1]:    from bin/rails:9:in `<main>'

2016-02-29T05:18:59.458586+00:00 heroku[web.1]: State changed from starting to crashed

2016-02-29T05:18:59.444429+00:00 heroku[web.1]: Process exited with status 1

依据

/app/vendor/bundle/ruby/2.2.0/gems/sass-rails-5.0.1/lib/sass/rails/helpers.rb:11:in `<top (required)>': uninitialized constant Sass::Script (NameError)

能够推測应该是gem文件里的sass-rails版本号的问题。

我突然想起了这个细节。

事实上依据第三版的书上面的Gemfile配置，书上的配置是gem 'sass-rails','5.0.0.beta1'，这一步在运行bundle install的时候就会报错了。

我是直接把beta1去掉。

由于这个错误，我把它改成了5.0.1版本号。

可是还是错误。上周弄得我一头雾水。今天又一次整理思路后。再查这个错误。

找到了答案：http://stackoverflow.com/questions/29594420/rails-tutorial-error-with-cloud-9

居然是要配置为gem 'sass-rails','5.0.2'。

成功正式部署Hello world。

近期看了《音乐的秘密》，一部介绍一首歌的幕后工作，作为程序猿应该也能相同看到对职业的一种尊重。

近期好像突然有了软肋，又突然有了铠甲。变得更加的坚定。