query.pp

class hosts {
  $hosts = query_facts('Class[Settings]', ['fqdn', 'ipaddress', 'hostname'])
  create_resources('hosts::host', $hosts)
}

define hosts::host (
  $fqdn,
  $ipaddress,
  $hostname,
) {
  host { $fqdn:
    ip           => $ipaddress,
    host_aliases => $hostname,
  }
}