Reads ClientMetadata records for a list of clients.

def MultiReadClientMetadata(self, client_ids):
    """Reads ClientMetadata records for a list of clients."""
    res = {}
    for client_id in client_ids:
      md = self.metadatas.get(client_id, None)
      if md is None:
        continue

      res[client_id] = rdf_objects.ClientMetadata(
          certificate=md.get("certificate"),
          fleetspeak_enabled=md.get("fleetspeak_enabled"),
          first_seen=md.get("first_seen"),
          ping=md.get("ping"),
          clock=md.get("clock"),
          ip=md.get("ip"),
          last_foreman_time=md.get("last_foreman_time"),
          last_crash_timestamp=md.get("last_crash_timestamp"),
          startup_info_timestamp=md.get("startup_info_timestamp"))

    return res