However, when I tried to find tutorials for using Clickpass with a Rails app, I couldn’t find any! How could it be! The pesudo code example Clickpass provided was for Java, I think, and thus it wasn’t any help to me. I was completely lost.
Then I realized that in the core underlying architecture of Clickpass is OpenID. Then it all made sense to me. I found a great tutorial on OpenID and Authlogic on a Railscasts episode (I am not using Authlogic for my site, though, but for the Open Translation project, I probably will.). So the following is a mixture of the Railscasts episode, ruby-openid gem, open_id_authentication plugin and Clickpass setup.
1. Install the gem and the plugin.
sudo gem install ruby-openid