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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.LeafReaderContext;
import org.apache.lucene.search.ConstantScoreQuery;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.FilteredQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.join.BitDocIdSetFilter;
import org.apache.lucene.search.join.ScoreMode;
import org.apache.lucene.search.join.ToParentBlockJoinQuery;
import org.apache.lucene.util.BitDocIdSet;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.mapper.MapperService;
import org.elasticsearch.index.mapper.object.ObjectMapper;
import org.elasticsearch.index.search.nested.NonNestedDocsFilter;
import java.io.IOException;
public class NestedQueryParser implements QueryParser {
public static final String NAME = "nested";
@Inject
public NestedQueryParser() {
}
@Override
public String[] names() {
return new String[]{NAME, Strings.toCamelCase(NAME)};
}
@Override
public Query parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
XContentParser parser = parseContext.parser();
Query query = null;
boolean queryFound = false;
Filter filter = null;
boolean filterFound = false;
float boost = 1.0f;
String path = null;
ScoreMode scoreMode = ScoreMode.Avg;
String queryName = null;
// we need a late binding filter so we can inject a parent nested filter inner nested queries
LateBindingParentFilter currentParentFilterContext = parentFilterContext.get();
LateBindingParentFilter usAsParentFilter = new LateBindingParentFilter();
parentFilterContext.set(usAsParentFilter);
try {
String currentFieldName = null;
XContentParser.Token token;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
if ("query".equals(currentFieldName)) {
queryFound = true;
query = parseContext.parseInnerQuery();
} else if ("filter".equals(currentFieldName)) {
filterFound = true;
filter = parseContext.parseInnerFilter();
} else {
throw new QueryParsingException(parseContext.index(), "[nested] query does not support [" + currentFieldName + "]");
}
} else if (token.isValue()) {
if ("path".equals(currentFieldName)) {
path = parser.text();
} else if ("boost".equals(currentFieldName)) {
boost = parser.floatValue();
} else if ("score_mode".equals(currentFieldName) || "scoreMode".equals(currentFieldName)) {
String sScoreMode = parser.text();
if ("avg".equals(sScoreMode)) {
scoreMode = ScoreMode.Avg;
} else if ("max".equals(sScoreMode)) {
scoreMode = ScoreMode.Max;
} else if ("total".equals(sScoreMode) || "sum".equals(sScoreMode)) {
scoreMode = ScoreMode.Total;
} else if ("none".equals(sScoreMode)) {
scoreMode = ScoreMode.None;
} else {
throw new QueryParsingException(parseContext.index(), "illegal score_mode for nested query [" + sScoreMode + "]");
}
} else if ("_name".equals(currentFieldName)) {
queryName = parser.text();
} else {
throw new QueryParsingException(parseContext.index(), "[nested] query does not support [" + currentFieldName + "]");
}
}
}
if (!queryFound && !filterFound) {
throw new QueryParsingException(parseContext.index(), "[nested] requires either 'query' or 'filter' field");
}
if (path == null) {
throw new QueryParsingException(parseContext.index(), "[nested] requires 'path' field");
}
if (query == null && filter == null) {
return null;
}
if (filter != null) {
query = new ConstantScoreQuery(filter);
}
MapperService.SmartNameObjectMapper mapper = parseContext.smartObjectMapper(path);
if (mapper == null) {
throw new QueryParsingException(parseContext.index(), "[nested] failed to find nested object under path [" + path + "]");
}
ObjectMapper objectMapper = mapper.mapper();
if (objectMapper == null) {
throw new QueryParsingException(parseContext.index(), "[nested] failed to find nested object under path [" + path + "]");
}
if (!objectMapper.nested().isNested()) {
throw new QueryParsingException(parseContext.index(), "[nested] nested object under path [" + path + "] is not of nested type");
}
BitDocIdSetFilter childFilter = parseContext.bitsetFilter(objectMapper.nestedTypeFilter());
usAsParentFilter.filter = childFilter;
// wrap the child query to only work on the nested path type
query = new FilteredQuery(query, childFilter);
BitDocIdSetFilter parentFilter = currentParentFilterContext;
if (parentFilter == null) {
parentFilter = parseContext.bitsetFilter(NonNestedDocsFilter.INSTANCE);
// don't do special parent filtering, since we might have same nested mapping on two different types
//if (mapper.hasDocMapper()) {
// // filter based on the type...
// parentFilter = mapper.docMapper().typeFilter();
//}
} else {
parentFilter = parseContext.bitsetFilter(parentFilter);
}
ToParentBlockJoinQuery joinQuery = new ToParentBlockJoinQuery(query, parentFilter, scoreMode);
joinQuery.setBoost(boost);
if (queryName != null) {
parseContext.addNamedQuery(queryName, joinQuery);
}
return joinQuery;
} finally {
// restore the thread local one...
parentFilterContext.set(currentParentFilterContext);
}
}
static ThreadLocal<LateBindingParentFilter> parentFilterContext = new ThreadLocal<>();
static class LateBindingParentFilter extends BitDocIdSetFilter {
BitDocIdSetFilter filter;
@Override
public int hashCode() {
return filter.hashCode();
}
@Override
public boolean equals(Object obj) {
return filter.equals(obj);
}
@Override
public String toString() {
return filter.toString();
}
@Override
public BitDocIdSet getDocIdSet(LeafReaderContext ctx) throws IOException {
return filter.getDocIdSet(ctx);
}
}
}