public static void writeTo(IndexMetaData indexMetaData, StreamOutput out) throws IOException {
   out.writeUTF(indexMetaData.index());
   out.writeLong(indexMetaData.version());
   out.writeByte(indexMetaData.state().id());
   writeSettingsToStream(indexMetaData.settings(), out);
   out.writeVInt(indexMetaData.mappings().size());
   for (MappingMetaData mappingMd : indexMetaData.mappings().values()) {
     MappingMetaData.writeTo(mappingMd, out);
   }
   out.writeVInt(indexMetaData.aliases().size());
   for (AliasMetaData aliasMd : indexMetaData.aliases().values()) {
     AliasMetaData.Builder.writeTo(aliasMd, out);
   }
   out.writeVInt(indexMetaData.customs().size());
   for (Map.Entry<String, Custom> entry : indexMetaData.customs().entrySet()) {
     out.writeUTF(entry.getKey());
     lookupFactorySafe(entry.getKey()).writeTo(entry.getValue(), out);
   }
 }
    public static void toXContent(
        IndexMetaData indexMetaData, XContentBuilder builder, ToXContent.Params params)
        throws IOException {
      builder.startObject(indexMetaData.index(), XContentBuilder.FieldCaseConversion.NONE);

      builder.field("version", indexMetaData.version());
      builder.field("state", indexMetaData.state().toString().toLowerCase(Locale.ENGLISH));

      boolean binary = params.paramAsBoolean("binary", false);

      builder.startObject("settings");
      for (Map.Entry<String, String> entry : indexMetaData.settings().getAsMap().entrySet()) {
        builder.field(entry.getKey(), entry.getValue());
      }
      builder.endObject();

      builder.startArray("mappings");
      for (Map.Entry<String, MappingMetaData> entry : indexMetaData.mappings().entrySet()) {
        if (binary) {
          builder.value(entry.getValue().source().compressed());
        } else {
          byte[] data = entry.getValue().source().uncompressed();
          XContentParser parser = XContentFactory.xContent(data).createParser(data);
          Map<String, Object> mapping = parser.mapOrdered();
          parser.close();
          builder.map(mapping);
        }
      }
      builder.endArray();

      for (Map.Entry<String, Custom> entry : indexMetaData.customs().entrySet()) {
        builder.startObject(entry.getKey(), XContentBuilder.FieldCaseConversion.NONE);
        lookupFactorySafe(entry.getKey()).toXContent(entry.getValue(), builder, params);
        builder.endObject();
      }

      builder.startObject("aliases");
      for (AliasMetaData alias : indexMetaData.aliases().values()) {
        AliasMetaData.Builder.toXContent(alias, builder, params);
      }
      builder.endObject();

      builder.endObject();
    }