Deploy Rails-3.1.3 on Heroku fails

Question

It fails with the following log errors :

2011-11-28T22:23:21+00:00 app[web.1]: /app/config/application.rb:84:in `<class:Application>': undefined method `full_gem_path' for nil:NilClass (NoMethodError)
2011-11-28T22:23:21+00:00 app[web.1]:   from /app/config/application.rb:30:in `<module:Rails3MongoidOmniauthSimple>'
2011-11-28T22:23:21+00:00 app[web.1]:   from /app/config/application.rb:29:in `<top (required)>'
2011-11-28T22:23:21+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.1.3/lib/rails/commands.rb:52:in `require'
2011-11-28T22:23:21+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.1.3/lib/rails/commands.rb:52:in `block in <top (required)>'
2011-11-28T22:23:21+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.1.3/lib/rails/commands.rb:49:in `tap'
2011-11-28T22:23:21+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.1.3/lib/rails/commands.rb:49:in `<top (required)>'
2011-11-28T22:23:21+00:00 app[web.1]:   from script/rails:6:in `require'
2011-11-28T22:23:21+00:00 app[web.1]:   from script/rails:6:in `<main>'
2011-11-28T22:23:22+00:00 heroku[web.1]: State changed from starting to crashed
2011-11-28T22:23:24+00:00 heroku[router]: Error H10 (App crashed) -> GET gitwatcher.com/ dyno= queue= wait= service= status=503 bytes=

... any idea ?

Answer 1

Check your /app/config/application.rb at line 84.

You are using a method that is not defined. Chances are the method is defined in some gem that is not available in the production environment.