Heroku: rails: getting "No such file to load -- URI (LoadError)"

Question

Just started using heroku with a rails application and I am not able to get the rails application start.

Ruby version on Heroku...

$ heroku run "ruby -v"

Running `ruby -v` attached to terminal... up, run.1
ruby 1.9.3p194 (2012-04-20 revision 35410) [x86_64-linux]

$ heroku ps

=== web: `bundle exec thin start -R config.ru -e $RAILS_ENV -p $PORT`
web.1: crashed for 6m

$ heroku logs

2012-08-17T10:06:49+00:00 heroku[web.1]: State changed from crashed to starting
2012-08-17T10:06:52+00:00 heroku[web.1]: Starting process with command `bundle exec thin start -R config.ru -e production -p 31657`
2012-08-17T10:06:54+00:00 app[web.1]: DEPRECATION WARNING: You have Rails 2.3-style plugins in vendor/plugins! Support for these plugins will be removed in Rails 4.0. Move them out and bundle them in your Gemfile, or fold them in to your app as lib/myplugin/* and config/initializers/myplugin.rb. See the release notes for more on this: http://weblog.rubyonrails.org/2012/1/4/rails-3-2-0-rc2-has-been-released. (called from <top (required)> at /app/config/environment.rb:5)
2012-08-17T10:06:54+00:00 app[web.1]: DEPRECATION WARNING: You have Rails 2.3-style plugins in vendor/plugins! Support for these plugins will be removed in Rails 4.0. Move them out and bundle them in your Gemfile, or fold them in to your app as lib/myplugin/* and config/initializers/myplugin.rb. See the release notes for more on this: http://weblog.rubyonrails.org/2012/1/4/rails-3-2-0-rc2-has-been-released. (called from <top (required)> at /app/config/environment.rb:5)
2012-08-17T10:06:56+00:00 app[web.1]: Connecting to database specified by DATABASE_URL
2012-08-17T10:06:57+00:00 app[web.1]: /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.6/lib/active_support/dependencies.rb:317:in `rescue in depend_on': No such file to load -- URI (LoadError)
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.6/lib/active_support/dependencies.rb:312:in `depend_on'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.6/lib/active_support/dependencies.rb:225:in `require_dependency'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:439:in `block (2 levels) in eager_load!'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:438:in `block in eager_load!'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:438:in `each'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:436:in `each'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/engine.rb:436:in `eager_load!'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/application/finisher.rb:53:in `block in <module:Finisher>'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:30:in `instance_exec'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:30:in `run'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:55:in `block in run_initializers'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:54:in `each'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/railtie/configurable.rb:30:in `method_missing'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/config/environment.rb:5:in `<top (required)>'
2012-08-17T10:06:57+00:00 app[web.1]:   from config.ru:3:in `require'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/initializable.rb:54:in `run_initializers'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.6/lib/rails/application.rb:136:in `initialize!'
2012-08-17T10:06:57+00:00 app[web.1]:   from config.ru:3:in `block in <main>'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:51:in `instance_eval'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/builder.rb:51:in `initialize'
2012-08-17T10:06:57+00:00 app[web.1]:   from config.ru:1:in `new'
2012-08-17T10:06:57+00:00 app[web.1]:   from config.ru:1:in `<main>'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/controllers/controller.rb:181:in `load_rackup_config'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/rack/adapter/loader.rb:33:in `eval'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/runner.rb:185:in `run_command'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/controllers/controller.rb:71:in `start'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/rack/adapter/loader.rb:33:in `load'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/lib/thin/runner.rb:151:in `run!'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/gems/thin-1.4.1/bin/thin:6:in `<top (required)>'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/bin/thin:23:in `load'
2012-08-17T10:06:57+00:00 app[web.1]:   from /app/vendor/bundle/ruby/1.9.1/bin/thin:23:in `<main>'
2012-08-17T10:06:58+00:00 heroku[web.1]: Process exited with status 1
2012-08-17T10:06:58+00:00 heroku[web.1]: State changed from starting to crashed
2012-08-17T10:07:00+00:00 heroku[router]: Error H10 (App crashed) -> GET boiling-bayou-5291.herokuapp.com/ dyno= queue= wait= service= status=503 bytes=
2012-08-17T10:07:00+00:00 heroku[router]: Error H10 (App crashed) -> GET boiling-bayou-5291.herokuapp.com/favicon.ico dyno= queue= wait= service= status=503 bytes=

The culprit seems to be the following above:

2012-08-17T10:06:57+00:00 app[web.1]: /app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.6/lib/active_support/dependencies.rb:317:in `rescue in depend_on': No such file to load -- URI (LoadError)

Clearly there is an issue with loading "URI" module.

Question is what's missing? Moreover ruby version that heroku reported was 1.9.3, then why is that in the logs above I see "1.9.1." Is that part of the problem?

Thanks much!

Answer 1

For the record, Mac OS X file systems are case-insensitive by default, whereas Linux filesystems are case-sensitive. Therefore URI and uri are the same on Mac, while require 'URI' will fail on Linux, as the file you're looking for is called uri.

Answer 2

Found the issue...

I was using require 'URI' in my code... if I change this to require 'uri' it works on heroku.

To be clear, require 'URI' was working on my local dev environment.