SAP Cloud Platform Custom Principal Attributes

Hello,

I use a custom identity provider to authenticate users on sap portal and I need to pass custom attributes with saml2 authentication to my sapui5 application.

When I try to retrieve connected user information in a sapui5 application I use this :

sap.ushell.Container.getService("UserInfo").getUser()

Unfortunatly the fields available are very limited (name, email and id), I would need more information.

Following the documentation about the use of a custom identity provider (with SAML2) I saw this specification :

Is there a list of all Principal Attribute availables somewhere?
Can we add custom attributes?
and of course is it possible to access those attributes in a sapui5 application? how?

Thanks for your help