@Override
    public Set<PersonAttributes> getPeopleWithMultivaluedAttributes(final Map<String, List<Object>> query,
                                                                    final PersonAttributeDaoFilter filter,
                                                                    final Set<PersonAttributes> resultPeople) {
        val people = new LinkedHashSet<PersonAttributes>();
        val username = usernameAttributeProvider.getUsernameFromQuery(query);
        val person = getPerson(username, resultPeople, filter);
        if (person != null) {
            people.add(person);
        }
        return people;
    }
Provides the ability to contact a URL resource to ask for attributes.
Support GET/POST endpoints, and provides the username in form of a parameter.
The response is expected to be a JSON map.

@author Misagh Moayyed
@since 7.1.0
support/cas-server-support-person-directory-core/src/main/java/org/apereo/cas/persondir/RestfulPersonAttributeDao.java