Adam Jensen has written up a new article today on how you can use the Zend_Auth component of the Zend Framework to authenticate your users in a few different ways based on a strategy selected.

For this example, we're going to allow our users to authenticate in one of multiple ways: e.g., against a database table, against an LDAP server, or by OpenID [1]. Zend_Auth already provides the necessary authentication adapters, so what we'll be concerned with here is how to implement all three systems without ending up in an FSUC situation.

He defines the code for the basic controller and a simple view that allows the user to select how they want to log in - email/password, username/password or OpenID. The model does all of the heavy lifting by letting the controller set the authentication type (strategy) and pulling in the correct Zend_Form instance along with its validation rules. Code is also included for the model and each of these.