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* 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.index.query;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.MultiDocValues;
import org.apache.lucene.search.*;
import org.apache.lucene.search.join.BitSetProducer;
import org.apache.lucene.search.join.JoinUtil;
import org.apache.lucene.search.join.ScoreMode;
import org.apache.lucene.search.similarities.Similarity;
import org.apache.lucene.util.SuppressForbidden;
import org.elasticsearch.Version;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.lucene.search.Queries;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.fielddata.IndexParentChildFieldData;
import org.elasticsearch.index.fielddata.plain.ParentChildIndexFieldData;
import org.elasticsearch.index.mapper.DocumentMapper;
import org.elasticsearch.index.mapper.internal.ParentFieldMapper;
import org.elasticsearch.index.query.support.InnerHitsQueryParserHelper;
import org.elasticsearch.index.query.support.XContentStructure;
import org.elasticsearch.index.search.child.ChildrenConstantScoreQuery;
import org.elasticsearch.index.search.child.ChildrenQuery;
import org.elasticsearch.index.search.child.ScoreType;
import org.elasticsearch.search.fetch.innerhits.InnerHitsContext;
import org.elasticsearch.search.fetch.innerhits.InnerHitsSubSearchContext;
import java.io.IOException;
/**
*
*/
@SuppressForbidden(reason="Old p/c queries still use filters")
public class HasChildQueryParser implements QueryParser {
public static final String NAME = "has_child";
private static final ParseField QUERY_FIELD = new ParseField("query", "filter");
private static final ParseField SCORE_MODE = new ParseField("score_mode", "score_type");
private final InnerHitsQueryParserHelper innerHitsQueryParserHelper;
@Inject
public HasChildQueryParser(InnerHitsQueryParserHelper innerHitsQueryParserHelper) {
this.innerHitsQueryParserHelper = innerHitsQueryParserHelper;
}
@Override
public String[] names() {
return new String[] { NAME };
}
@Override
public Query parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
XContentParser parser = parseContext.parser();
boolean queryFound = false;
float boost = 1.0f;
String childType = null;
ScoreType scoreType = ScoreType.NONE;
int minChildren = 0;
int maxChildren = 0;
int shortCircuitParentDocSet = 8192;
String queryName = null;
InnerHitsSubSearchContext innerHits = null;
String currentFieldName = null;
XContentParser.Token token;
XContentStructure.InnerQuery iq = null;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (parseContext.isDeprecatedSetting(currentFieldName)) {
// skip
} else if (token == XContentParser.Token.START_OBJECT) {
// Usually, the query would be parsed here, but the child
// type may not have been extracted yet, so use the
// XContentStructure.<type> facade to parse if available,
// or delay parsing if not.
if (parseContext.parseFieldMatcher().match(currentFieldName, QUERY_FIELD)) {
iq = new XContentStructure.InnerQuery(parseContext, childType == null ? null : new String[] { childType });
queryFound = true;
} else if ("inner_hits".equals(currentFieldName)) {
innerHits = innerHitsQueryParserHelper.parse(parseContext);
} else {
throw new QueryParsingException(parseContext, "[has_child] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if ("type".equals(currentFieldName) || "child_type".equals(currentFieldName) || "childType".equals(currentFieldName)) {
childType = parser.text();
} else if (parseContext.parseFieldMatcher().match(currentFieldName, SCORE_MODE)) {
scoreType = ScoreType.fromString(parser.text());
} else if ("boost".equals(currentFieldName)) {
boost = parser.floatValue();
} else if ("min_children".equals(currentFieldName) || "minChildren".equals(currentFieldName)) {
minChildren = parser.intValue(true);
} else if ("max_children".equals(currentFieldName) || "maxChildren".equals(currentFieldName)) {
maxChildren = parser.intValue(true);
} else if ("short_circuit_cutoff".equals(currentFieldName)) {
shortCircuitParentDocSet = parser.intValue();
} else if ("_name".equals(currentFieldName)) {
queryName = parser.text();
} else {
throw new QueryParsingException(parseContext, "[has_child] query does not support [" + currentFieldName + "]");
}
}
}
if (!queryFound) {
throw new QueryParsingException(parseContext, "[has_child] requires 'query' field");
}
if (childType == null) {
throw new QueryParsingException(parseContext, "[has_child] requires 'type' field");
}
Query innerQuery = iq.asQuery(childType);
if (innerQuery == null) {
return null;
}
innerQuery.setBoost(boost);
DocumentMapper childDocMapper = parseContext.mapperService().documentMapper(childType);
if (childDocMapper == null) {
throw new QueryParsingException(parseContext, "[has_child] No mapping for for type [" + childType + "]");
}
ParentFieldMapper parentFieldMapper = childDocMapper.parentFieldMapper();
if (parentFieldMapper.active() == false) {
throw new QueryParsingException(parseContext, "[has_child] _parent field has no parent type configured");
}
if (innerHits != null) {
ParsedQuery parsedQuery = new ParsedQuery(innerQuery, parseContext.copyNamedQueries());
InnerHitsContext.ParentChildInnerHits parentChildInnerHits = new InnerHitsContext.ParentChildInnerHits(innerHits.getSubSearchContext(), parsedQuery, null, parseContext.mapperService(), childDocMapper);
String name = innerHits.getName() != null ? innerHits.getName() : childType;
parseContext.addInnerHits(name, parentChildInnerHits);
}
String parentType = parentFieldMapper.type();
DocumentMapper parentDocMapper = parseContext.mapperService().documentMapper(parentType);
if (parentDocMapper == null) {
throw new QueryParsingException(parseContext, "[has_child] Type [" + childType + "] points to a non existent parent type ["
+ parentType + "]");
}
if (maxChildren > 0 && maxChildren < minChildren) {
throw new QueryParsingException(parseContext, "[has_child] 'max_children' is less than 'min_children'");
}
BitSetProducer nonNestedDocsFilter = null;
if (parentDocMapper.hasNestedObjects()) {
nonNestedDocsFilter = parseContext.bitsetFilter(Queries.newNonNestedFilter());
}
// wrap the query with type query
innerQuery = Queries.filtered(innerQuery, childDocMapper.typeFilter());
final Query query;
final ParentChildIndexFieldData parentChildIndexFieldData = parseContext.getForField(parentFieldMapper.fieldType());
if (parseContext.indexVersionCreated().onOrAfter(Version.V_2_0_0_beta1)) {
query = joinUtilHelper(parentType, parentChildIndexFieldData, parseContext.similarityService().similarity(), parentDocMapper.typeFilter(), scoreType, innerQuery, minChildren, maxChildren);
} else {
// TODO: use the query API
Filter parentFilter = new QueryWrapperFilter(parentDocMapper.typeFilter());
if (minChildren > 1 || maxChildren > 0 || scoreType != ScoreType.NONE) {
query = new ChildrenQuery(parentChildIndexFieldData, parentType, childType, parentFilter, innerQuery, scoreType, minChildren,
maxChildren, shortCircuitParentDocSet, nonNestedDocsFilter);
} else {
query = new ChildrenConstantScoreQuery(parentChildIndexFieldData, innerQuery, parentType, childType, parentFilter,
shortCircuitParentDocSet, nonNestedDocsFilter);
}
}
if (queryName != null) {
parseContext.addNamedQuery(queryName, query);
}
query.setBoost(boost);
return query;
}
public static Query joinUtilHelper(String parentType, ParentChildIndexFieldData parentChildIndexFieldData, Similarity similarity, Query toQuery, ScoreType scoreType, Query innerQuery, int minChildren, int maxChildren) throws IOException {
ScoreMode scoreMode;
// TODO: move entirely over from ScoreType to org.apache.lucene.join.ScoreMode, when we drop the 1.x parent child code.
switch (scoreType) {
case NONE:
scoreMode = ScoreMode.None;
break;
case MIN:
scoreMode = ScoreMode.Min;
break;
case MAX:
scoreMode = ScoreMode.Max;
break;
case SUM:
scoreMode = ScoreMode.Total;
break;
case AVG:
scoreMode = ScoreMode.Avg;
break;
default:
throw new UnsupportedOperationException("score type [" + scoreType + "] not supported");
}
// 0 in pre 2.x p/c impl means unbounded
if (maxChildren == 0) {
maxChildren = Integer.MAX_VALUE;
}
return new LateParsingQuery(toQuery, innerQuery, minChildren, maxChildren, parentType, scoreMode, parentChildIndexFieldData, similarity);
}
/**
* A query that rewrites into another query using
* {@link JoinUtil#createJoinQuery(String, Query, Query, IndexSearcher, ScoreMode, MultiDocValues.OrdinalMap, int, int)}
* that executes the actual join.
*
* This query is exclusively used by the {@link HasChildQueryBuilder} and {@link HasParentQueryBuilder} to get access
* to the {@link DirectoryReader} used by the current search in order to retrieve the {@link MultiDocValues.OrdinalMap}.
* The {@link MultiDocValues.OrdinalMap} is required by {@link JoinUtil} to execute the join.
*/
// TODO: Find a way to remove this query and let doToQuery(...) just return the query from JoinUtil.createJoinQuery(...)
public final static class LateParsingQuery extends Query {
private final Query toQuery;
private final Query innerQuery;
private final int minChildren;
private final int maxChildren;
private final String parentType;
private final ScoreMode scoreMode;
private final ParentChildIndexFieldData parentChildIndexFieldData;
private final Similarity similarity;
private final Object identity = new Object();
LateParsingQuery(Query toQuery, Query innerQuery, int minChildren, int maxChildren, String parentType, ScoreMode scoreMode, ParentChildIndexFieldData parentChildIndexFieldData, Similarity similarity) {
this.toQuery = toQuery;
this.innerQuery = innerQuery;
this.minChildren = minChildren;
this.maxChildren = maxChildren;
this.parentType = parentType;
this.scoreMode = scoreMode;
this.parentChildIndexFieldData = parentChildIndexFieldData;
this.similarity = similarity;
}
@Override
public Query rewrite(IndexReader reader) throws IOException {
if (getBoost() != 1.0F) {
return super.rewrite(reader);
}
if (reader instanceof DirectoryReader) {
String joinField = ParentFieldMapper.joinField(parentType);
IndexSearcher indexSearcher = new IndexSearcher(reader);
indexSearcher.setQueryCache(null);
indexSearcher.setSimilarity(similarity);
IndexParentChildFieldData indexParentChildFieldData = parentChildIndexFieldData.loadGlobal((DirectoryReader) reader);
MultiDocValues.OrdinalMap ordinalMap = ParentChildIndexFieldData.getOrdinalMap(indexParentChildFieldData, parentType);
return JoinUtil.createJoinQuery(joinField, innerQuery, toQuery, indexSearcher, scoreMode, ordinalMap, minChildren, maxChildren);
} else {
if (reader.leaves().isEmpty() && reader.numDocs() == 0) {
// asserting reader passes down a MultiReader during rewrite which makes this
// blow up since for this query to work we have to have a DirectoryReader otherwise
// we can't load global ordinals - for this to work we simply check if the reader has no leaves
// and rewrite to match nothing
return new MatchNoDocsQuery();
}
throw new IllegalStateException("can't load global ordinals for reader of type: " + reader.getClass() + " must be a DirectoryReader");
}
}
// Even though we only cache rewritten queries it is good to let all queries implement hashCode() and equals():
// We can't check for actually equality here, since we need to IndexReader for this, but
// that isn't available on all cases during query parse time, so instead rely on identity:
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
if (!super.equals(o)) return false;
LateParsingQuery that = (LateParsingQuery) o;
return identity.equals(that.identity);
}
@Override
public int hashCode() {
int result = super.hashCode();
result = 31 * result + identity.hashCode();
return result;
}
@Override
public String toString(String s) {
return "LateParsingQuery {parentType=" + parentType + "}";
}
}
}