Override user authentication with external credentials

Question

I'm working on a site running WordPress along with a vBulletin forum. The user base is registered on vBulletin. I need to allow users to appear logged in on WordPress as well for the sole purpose of posting comments with their forum user.

The user must not be replicated on WordPress, so every solution involving the creation of users in the WordPress database is not applicable.

Users recognized in this way need not have any admin or publishing privileges, only the ability to comment so that their comment appears under their forum username.

I had written a simple plugin which was working on an older version, but it's not working anymore with the most recent version of WordPress (3.3.2 at the moment). That solution relied on overriding the pluggable functions wp_validate_auth_cookie and get_userdata.

What are the correct steps to take in order to implement this functionality?

Answer 1

There should be no problem with any normal WordPress-vBulletin bridge which syncs user data between the two platforms. Just make sure that synced users have the default role of "Subscriber". This allows them to only post comments, and not to create or edit posts.

Answer 2

Have you tried Disqus?

They have a plugin that essentially "hijacks" the WP comments function and allows anonymous posting I am fairly certain that it will sync with the user database if they want to post as their WP username.

I have not used it yet but it's on my todo list to implement so unfortunately I can't run you through an install.