/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you under
* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.elasticsearch.search.fetch.subphase;
import org.apache.lucene.index.LeafReader;
import org.apache.lucene.index.SortedDocValues;
import org.apache.lucene.util.BytesRef;
import org.elasticsearch.ExceptionsHelper;
import org.elasticsearch.index.mapper.ParentFieldMapper;
import org.elasticsearch.search.SearchHitField;
import org.elasticsearch.search.fetch.FetchSubPhase;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
public final class ParentFieldSubFetchPhase implements FetchSubPhase {
@Override
public void hitExecute(SearchContext context, HitContext hitContext) {
if (context.storedFieldsContext() != null && context.storedFieldsContext().fetchFields() == false) {
return ;
}
ParentFieldMapper parentFieldMapper = context.mapperService().documentMapper(hitContext.hit().getType()).parentFieldMapper();
if (parentFieldMapper.active() == false) {
return;
}
String parentId = getParentId(parentFieldMapper, hitContext.reader(), hitContext.docId());
if (parentId == null) {
// hit has no _parent field. Can happen for nested inner hits if parent hit is a p/c document.
return;
}
Map<String, SearchHitField> fields = hitContext.hit().fieldsOrNull();
if (fields == null) {
fields = new HashMap<>();
hitContext.hit().fields(fields);
}
fields.put(ParentFieldMapper.NAME, new SearchHitField(ParentFieldMapper.NAME, Collections.singletonList(parentId)));
}
public static String getParentId(ParentFieldMapper fieldMapper, LeafReader reader, int docId) {
try {
SortedDocValues docValues = reader.getSortedDocValues(fieldMapper.name());
if (docValues == null || docValues.advanceExact(docId) == false) {
// hit has no _parent field.
return null;
}
BytesRef parentId = docValues.binaryValue();
return parentId.length > 0 ? parentId.utf8ToString() : null;
} catch (IOException e) {
throw ExceptionsHelper.convertToElastic(e);
}
}
}