Plugin Page: http://wordpress.org/extend/plugins/openid/ 

Source: http://diso.googlecode.com/svn/wordpress/openid/

Stored Data

The OpenID plugin stores data in various WordPress tables, as outlined here.  


The following global settings are stored in the options table:

User Meta

The following options are stored per user in the usermeta table:

Post Meta

Previous versions of the plugin added an 'openid' column to the comments table to track which comments were left using an OpenID.  That has been removed in version 3.0 of the plugin, and this data is instead stored in the postmeta table:

OpenID Identities

The plugin adds one table to the WordPress database named 'openid_identities'.  This table keeps track of the OpenIDs associated with each user.  The current schema is not ideal, but I've opted not to mess with it in order to ensure an easier upgrade path from previous versions of the plugin.  If this bug is ever fixed in WordPress, I plan do away with this table entirely.  The current table columns:

Hidden Options

In addition to the hidden options mentioned above in the WordPress options table, the following constants effect the behavior of the plugin.  They should be defined in wp-config.php.

For Plugin Authors

Starting with version 3.0, there are a number of documented methods of extending the wp-openid plugin.  Other plugins should only ever use the public methods or the hooks defined below for extending wp-openid.  If additional functions or hooks are needed, please send a message to the DiSo mailing list.

Public Functions

Public functions are present and fully documented in the file openid.php.  They are listed here for reference, but the documentation in the code is much more in-depth.

Extending the OpenID Consumer

The OpenID Consumer provides a small handful of hooks for use by other plugins.

Extending the OpenID Provider

The built-in OpenID Provider includes a number of hooks which can be implemented to provide additional functionality.  All of the simple registration (sreg) features of the OpenID Provider are provided using these hooks, as can be seen in the file server_ext.php.

Extending the OpenID Provider - Simple Registration

The Simple Registration OpenID extension defines 9 attributes which can be requested from an OpenID provider to aid a user in registering at a new relying party.  The standard WordPress user profile is sufficient to populate three of these attributes: fullname, email, and nickname.  For each sreg attribute a filter is called which allows other plugins to provide and/or override a value.