Prerequisites

Provides a thin wrapper around the excellent ruby-openid gem from JanRan. Be sure to install that first:

gem install ruby-openid

To understand what OpenID is about and how it works, it helps to read the documentation for lib/openid/consumer.rb from that gem.

The specification used is http://openid.net/specs/openid-authentication-2_0.html.

First Steps

After installing this plugin, you need to:

rake open_id_authentication:db:create

Then, you need a default route:

map.root :controller => 'welcome'

Then, anywhere you want users to be authenticated in your controller, just do:

before_filter :signin_required

And you're done!

Helpers

The following helpers are available in your controller and views:

* current_user - returns the current authenticated user
* signed_in? - tells you whether or not the current session is authenticated

Routes

This engine adds a session resource to your routes, as well as two handy URLs, "/signin" and "/signout", which do what they sound like they should.

Assumptions

This engine currently assumes the existence of a User model. I know, that's a little dumb, but as a first pass, it seems like a reasonable assumption. As such, the migration adds an identity_url to the users table.

Also, it assumes you're treating your users as RESTful resources, so if you have validations on your user model, upon account creation, if the user model isn't valid, the user will be redirected to edit_user_url.

I hope to get both of those assumptions moved to a yaml or something soon.

Credits

This is actually mostly a repackaging/following of the steps from the actual open_id_authentication plugin, found here: http://github.com/rails/open_id_authentication/tree/master

I didn't know anything about Rails engines until I heard a talk by Mike Perham, whose github profile you can find here: http://github.com/mperham