Deploying sinatra app (with config.ru) on heroku cedar stack

Question

I'm trying to refactor my sinatra code to separate my main file into separate files, using some tips from this response, and I'm having troubles deploying to heroku.

Previously I didn't have a config.ru file, and just used my Procfile, which was:

web: bundle exec ruby web.rb -p $PORT

as per this article.

From the refactor, I've now changed my Procfile to

web: bundle exec thin -R config.ru start -p $PORT

With my config.ru file being

root = ::File.dirname(__FILE__)
require ::File.join( root, 'web' )
run MyApp.new

And my web.rb file being contained around a class definition

class MyApp < Sinatra::Application
  # ...
end

This works on my local development computer, but when I deploy to heroku, I get

2011-12-01T11:21:54+00:00 app[web.1]: bundler: command not found: thin
2011-12-01T11:21:54+00:00 app[web.1]: Install missing gem executables with `bundle install`
2011-12-01T11:21:56+00:00 heroku[web.1]: State changed from starting to crashed
2011-12-01T11:22:01+00:00 heroku[router]: Error H10 (App crashed) -> GET [my app].herokuapp.com/ dyno= queue= wait= service= status=503 bytes=
2011-12-01T11:22:02+00:00 heroku[router]: Error H10 (App crashed) -> GET [my app].herokuapp.com/favicon.ico dyno= queue= wait= service= status=503 bytes=

Is thin not installed on heroku? Or is there some other way of running my app on heroku with the changes?

Answer 1

I had to update my Procfile because the RACK_ENV isn't passed into the heroku environment. The Procfile became:

web: bundle exec thin -R config.ru start -p $PORT -e $RACK_ENV