/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search 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.search.ConstantScoreQuery;
import org.apache.lucene.search.DeletionAwareConstantScoreQuery;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.Query;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.cache.filter.support.CacheKeyFilter;
import java.io.IOException;
/**
* @author kimchy (shay.banon)
*/
public class ConstantScoreQueryParser implements QueryParser {
public static final String NAME = "constant_score";
@Inject public ConstantScoreQueryParser() {
}
@Override public String[] names() {
return new String[]{NAME, Strings.toCamelCase(NAME)};
}
@Override public Query parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
XContentParser parser = parseContext.parser();
Filter filter = null;
Query query = null;
float boost = 1.0f;
boolean cache = false;
CacheKeyFilter.Key cacheKey = null;
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 ("filter".equals(currentFieldName)) {
filter = parseContext.parseInnerFilter();
} else if ("query".equals(currentFieldName)) {
query = parseContext.parseInnerQuery();
}
} else if (token.isValue()) {
if ("boost".equals(currentFieldName)) {
boost = parser.floatValue();
} else if ("_cache".equals(currentFieldName)) {
cache = parser.booleanValue();
} else if ("_cache_key".equals(currentFieldName) || "_cacheKey".equals(currentFieldName)) {
cacheKey = new CacheKeyFilter.Key(parser.text());
}
}
}
if (filter == null && query == null) {
throw new QueryParsingException(parseContext.index(), "[constant_score] requires either 'filter' or 'query' element");
}
if (filter != null) {
// cache the filter if possible needed
if (cache) {
filter = parseContext.cacheFilter(filter, cacheKey);
}
Query query1 = new DeletionAwareConstantScoreQuery(filter);
query1.setBoost(boost);
return query1;
}
// Query
query = new ConstantScoreQuery(query);
query.setBoost(boost);
return query;
}
}