@Override
    public Optional<Reindexing.Status> status(String clusterName, String documentType) {
        return Optional.ofNullable(clusters.get(clusterName)).map(cluster -> cluster.ready().get(documentType));
    }
The reindexing status of each of the clusters of this application.
configserver/src/main/java/com/yahoo/vespa/config/server/application/ApplicationReindexing.java