default CompletableFuture<Integer> getMasterInfoPort() {
    return getClusterMetrics(EnumSet.of(Option.MASTER_INFO_PORT))
      .thenApply(ClusterMetrics::getMasterInfoPort);
  }
Get the info port of the current master if one is available.
@return master info port
hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncAdmin.java