Extracting Values from a Custom Principal

[Tom Zeller]

>> Scott said he had implemented a custom principal to support custom attributes from external auth.   He didn't remember if was implemented based on a Map.   I  looked if he was referring to https://issues.shibboleth.net/jira/browse/IDP-832 and idp-authn-api/src/main/java/net/shibboleth/idp/authn/principal/IdPAttributePrincipal.java its not based on a Map but only a single attribute/value pair.   So I'm re-thinking the design but I need to know more about how it works in practice.
> 
> I created it for Misagh and just generally so that it was possible to pass back attributes from an External Authn integration.
> 
> I don't believe I have (yet) actually created any resolver plugins to operate on them, but the natural thing to do would be to just write a DataConnector that pulls them all out as the result of the connector.

As mentioned a couple of dev calls ago, I also need a DataConnector which returns/pulls IdPAttributes from IdPAttributePrincipals, so I plan on doing that. It’s not the general case of a PrincipalDataConnector (IDP-926), so I created a separate issue (IDP-941).