heroku getting server errors - where can I find them in the log?

Question

Ruby on Rails app called 'product9'

For one particular page for a new feature I am getting

We're sorry, but something went wrong.

I use

heroku logs --app product9 -n200

to look at the logs but all I am seeing for the page that is generating the error is:

2013-01-30T19:06:02+00:00 heroku[router]: at=info method=GET 
path=/medicaid host=product9.herokuapp.com fwd=173.14.167.133 dyno=web.1 queue=0
wait=11ms connect=31ms service=189ms status=500 bytes=643

Notice the status 500.

How can I find out more info on exactly what the issue is, i.e. how can I find a more detailed error message?

fyi: I downloaded the app locally but don't get that error. I had to run a rake db:migrate but I've also done that on Heroku (heroku run rake db:migrate).

I've turned on Airbrake and Exceptional and restarted the app but this didn't seem to help or generate any error email.

Answer 1

The answer was to turn on Airbrake.

I also restarted the server (heroku server restart --app myapp).

Now I get lots of fun details I can work with! Like:

Started GET "/medicaid" for 173.14.167.133 at 2013-01-30 20:45:38 +0000
2013-01-30T20:45:37+00:00 heroku[web.1]: State changed from starting to up
2013-01-30T20:45:41+00:00 app[web.1]:     5: 
2013-01-30T20:45:41+00:00 app[web.1]:     4:    - javascript_include_tag "fullcalendar", "medicaid"
2013-01-30T20:45:41+00:00 app[web.1]: 
2013-01-30T20:45:41+00:00 app[web.1]: ActionView::Template::Error (medicaid.css isn't precompiled):
2013-01-30T20:45:41+00:00 app[web.1]:     2:    - stylesheet_link_tag "medicaid"
2013-01-30T20:45:41+00:00 app[web.1]:     1: - content_for :stylesheets do
2013-01-30T20:45:41+00:00 app[web.1]:     3: - content_for :javascripts do
2013-01-30T20:45:41+00:00 app[web.1]:   app/views/medicaid/index.html.haml:2:in `block in _app_views_medicaid_index_html_haml__252759609716080826_41268600'
...