/*
* 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.engine;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.search.IndexSearcher;
import java.io.IOException;
/**
* Extension point to add custom functionality at request time to the {@link DirectoryReader}
* and {@link IndexSearcher} managed by the {@link Engine}.
*/
public interface IndexSearcherWrapper {
/**
* @param reader The provided directory reader to be wrapped to add custom functionality
* @return a new directory reader wrapping the provided directory reader or if no wrapping was performed
* the provided directory reader
*/
DirectoryReader wrap(DirectoryReader reader) throws IOException;
/**
* @param engineConfig The engine config which can be used to get the query cache and query cache policy from
* when creating a new index searcher
* @param searcher The provided index searcher to be wrapped to add custom functionality
* @return a new index searcher wrapping the provided index searcher or if no wrapping was performed
* the provided index searcher
*/
IndexSearcher wrap(EngineConfig engineConfig, IndexSearcher searcher) throws EngineException;
}