[RUS-WG] list role operation

[Xiaoyu Chen]

About _RUS::listAssignedRoles_
The interface was defined according to the configuration informaiton defined in section 4 (version 1.7 and version 1.9). As both documents clarified, the access control model for RUS should be role-based. The operation is then used to return configuration information to the client about assigned roles by RUS internal access control model. The roles defined here differentiate from ones defined in VOMS, but could be same depending on project-specific role configuraiton and allocation mechanism. 
It is interesting to know the RUS should not restrict on role-based access control model. Then the configuration (section 4.1) should be removed as well?
I generally agree on this operation has nothing to do with RUS logics. But i got an interesting use case here which contributed to this definition:
A Portlet-based RUS client, that automatically filters unauthorised portlets for client-side interactions. Then the operations can be used to query assigned roles to a particular user, and only display related portlets in a single Web portal. 

Anyway, this operation can be custom defined within an implementation. 

(traker: http://forge.ogf.org/sf/go/artf5887?nav=1 <http://forge.ogf.org/sf/go/artf5887?nav=1> )

cheers!