Completable create(Mapping mapping) {
    Objects.requireNonNull(mapping, "mapping");
    Map<String, String> newMap =  mapping.fields()
            .entrySet()
            .stream()
            .collect(Collectors.toMap(Map.Entry::getKey, e -> e.getValue().name()));

    return create(newMap);
  }
Creates elastic search mapping (index) on the cluster
criteria/elasticsearch/src/org/immutables/criteria/elasticsearch/IndexOps.java