Working to add support for multi factor authentication to WildFly one requirement is an arbitrary list of attributes being specified beyond the usual username and password.

One such example would be OTP but other values could be provided.

This issue is to add a dynamic implementation of Evidence allowing named attributes to be added, our login form can initially pass a username and password but it could be expanded to ask for additional parameters which will be populated in the Evidence.

Our realms which support username / password evidence validation should also support this new dynamic Evidence or we should add a mechanism to convert to supported types. It is also worth considering how this would relate to transformation / mapping as well.