paulrosen

If you have set up a WordPress installation as a subfolder of a Rails App, this plugin will make your users login with your Rails app. That is, there is no WordPress login; your users will be logged in if they are logged in to Rails, and they are not logged in if not.
The WordPress installation needs to be on the same domain as the Rails app because it needs to access the same cookie.

Rails Login

The Rails Login plugin enables a WordPress installation that is in a subfolder of a Rails application to use the Rails authentication instead of its o …

This calls back to a web service to get theme information, so that it is easy to keep the rails and WP sides in sync.
It is designed to be used when a Rails application wishes to contain WordPress content. This allows the WordPress pages 
to directly use the styles of the Rails application so that it will always match, even when the Rails app changes.
It is also useful when the header of the page changes, for instance, if new menu items can appear depending on the state of the 
application.
And finally, if you want to POST back to the Rails app (for instance, to log in), you need the CSRF to be set in the page’s header, 
and that needs to come from the Rails session.
NOTE: This might take some tweaking depending on the theme you are using. It successfully works with the default 2011 theme 
and the Hybrid theme.
It requires an entry point in your Rails controller that returns three things: 
1. a section that is put in the header to load stylesheets and javascript, 
1. a section that is loaded at the top of the body, and 
1. a section that is loaded at the bottom of the body.
There is one main option in the plugin to tell it the base URL of the Rails app. The rails app is expected to respond to the 
following URL:
<pre><code>/wrapper
</code></pre>
This also supplies a convenience option to add classes to the so that you can match the body styles in your rails app.
<h3>Troubleshooting</h3>
<ol>
<li>My theme doesn’t show up at all.</li>
</ol>
Turn on WP_DEBUG in wp_config.php and see if there is an error message printed to the page.

Rails Theme

This calls back to a Rails (or other) web service to get theme information, so that it is easy to keep the rails and WP sides in sync.

Rails Login vs Rails Theme