Rails: Omniauth: Github provider doesn't quite work - ruby-on-rails

Question

I recently forked https://github.com/fortuity/rails3-mongoid-omniauth and tried to get login working for different providers. It works for Twitter and Facebook (You can try it out at http://jgodse-omniauth-mongoid.heroku.com/), but I couldn't get it working for Github. The code snapshot is here at github.
My environment looks like this:
$ heroku info
=== jgodse-omniauth-mongoid
Web URL: http://jgodse-omniauth-mongoid.heroku.com/
Git Repo: git#heroku.com:jgodse-omniauth-mongoid.git
Dynos: 1
Workers: 0
Repo size: 7M
Slug size: 5M
Stack: bamboo-mri-1.9.2
Data size: (empty)
Addons: Basic Logging, MongoHQ MongoHQ Free, Shared Database 5MB
Owner: xxxxx#yyy.com
Jay#JAY-PC ~/rapps/rails3-mongoid-omniauth (master)
$ heroku config --long
BUNDLE_WITHOUT => development:test
DATABASE_URL => postgres://xxxxxxxxxxxxxxxxxxxx.compute-1.amazonaws.com/rrretnhwhj
FACEBOOK_APP_ID => xxxxxxxxxxxxxxxxxxxx
FACEBOOK_APP_SECRET => xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
GITHUB_CLIENT_ID => xxxxxxxxxxxxxxxxxxxxx
GITHUB_SECRET => xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
LANG => en_US.UTF-8
MONGOHQ_URL => mongodb://heroku:9xxxxxxxxxxxxxxxx.mongohq.com:27098/app527030
RACK_ENV => production
SHARED_DATABASE_URL => postgres://xxxxxxxxxxxxxxxxxxxxx.compute-1.amazonaws.com/rrretnhwhj
TWITTER_KEY => xxxxxxxxxxxxxxxxxxx
TWITTER_SECRET => xxxxxxxxxxxxxxxxxxxxxxxxxxxx
My github information for "OAuth Application: Jay's Rails3 Mongoid OAuth" is as follows (from my app profile page):
Authorization Token: https://github.com/login/oauth/authorize
Access Token URL: https://github.com/login/oauth/access_token
URL: http://jgodse-omniauth-mongoid.heroku.com/
Callback URL: http://jgodse-omniauth-mongoid.heroku.com/
Client ID: xxxxxxx
Secret: xxxxxxxxxxxxxxxx
The client and secret are set as environment variables in omniauth.rb
The authentication happens, but it redirects to http://jgodse-omniauth-mongoid.heroku.com/?error=redirect_uri_mismatch and I haven't apparently logged in. If I change the Callback URL to http://jgodse-omniauth-mongoid.heroku.com/callback, the application crashes.
What am I missing to get github authentication to work?

Answer 1

I don't fu%^&*g believe this.
I went to github.com where the application secret, key, url, callback is configured and removed the trailing slash from the "Callback URL" and "URL", and it worked.
URL: http://jgodse-omniauth-mongoid.heroku.com
Callback URL: http://jgodse-omniauth-mongoid.heroku.com
This is nuts! Twitter wants the trailing slash on the callback but Github does not. Github and twitter should allow both and then trim it automatically if needed.