Register the _ts_routing_hash value format as named writeable (elastic#113452) (elastic#113463)

In elastic#113373 we added a yaml test that can exercise the path of parsing
`_ts_routing_hash` values however, the doc value format was not already
registered in the `NamedWriteableRegistry`.

This makes the `TimeSeriesRoutingHashFieldType` doc value format
`NamedWriteable` available in the `NamedWriteableRegistry`

(cherry picked from commit d07d167)
Signed-off-by: Andrei Dan <[email protected]>

Author: andreidan

server/src/main/java/org/elasticsearch/index/mapper/TimeSeriesRoutingHashFieldMapper.java

@@ -48,10 +48,12 @@ public class TimeSeriesRoutingHashFieldMapper extends MetadataFieldMapper {
     public static final TypeParser PARSER = new FixedTypeParser(c -> c.getIndexSettings().getMode().timeSeriesRoutingHashFieldMapper());
     static final NodeFeature TS_ROUTING_HASH_FIELD_PARSES_BYTES_REF = new NodeFeature("tsdb.ts_routing_hash_doc_value_parse_byte_ref");
 
+    public static DocValueFormat TS_ROUTING_HASH_DOC_VALUE_FORMAT = TimeSeriesRoutingHashFieldType.DOC_VALUE_FORMAT;
+
     static final class TimeSeriesRoutingHashFieldType extends MappedFieldType {
 
         private static final TimeSeriesRoutingHashFieldType INSTANCE = new TimeSeriesRoutingHashFieldType();
-        private static final DocValueFormat DOC_VALUE_FORMAT = new DocValueFormat() {
+        static final DocValueFormat DOC_VALUE_FORMAT = new DocValueFormat() {
 
             @Override
             public String getWriteableName() {

server/src/main/java/org/elasticsearch/search/SearchModule.java

@@ -276,6 +276,7 @@
 
 import static java.util.Collections.unmodifiableMap;
 import static java.util.Objects.requireNonNull;
+import static org.elasticsearch.index.mapper.TimeSeriesRoutingHashFieldMapper.TS_ROUTING_HASH_DOC_VALUE_FORMAT;
 
 /**
  * Sets up things that can be done at search time like queries, aggregations, and suggesters.
@@ -1023,6 +1024,7 @@ private void registerValueFormats() {
         registerValueFormat(DocValueFormat.BINARY.getWriteableName(), in -> DocValueFormat.BINARY);
         registerValueFormat(DocValueFormat.UNSIGNED_LONG_SHIFTED.getWriteableName(), in -> DocValueFormat.UNSIGNED_LONG_SHIFTED);
         registerValueFormat(DocValueFormat.TIME_SERIES_ID.getWriteableName(), in -> DocValueFormat.TIME_SERIES_ID);
+        registerValueFormat(TS_ROUTING_HASH_DOC_VALUE_FORMAT.getWriteableName(), in -> TS_ROUTING_HASH_DOC_VALUE_FORMAT);
     }
 
     /**