/**
* This file is part of Graylog2.
*
* Graylog2 is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Graylog2 is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Graylog2. If not, see <http://www.gnu.org/licenses/>.
*/
package org.graylog2.indexer.results;
import org.apache.shiro.crypto.hash.Md5Hash;
import org.elasticsearch.action.search.ClearScrollResponse;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.Client;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.search.SearchHits;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.List;
public class ScrollResult extends IndexQueryResult {
private static final Logger LOG = LoggerFactory.getLogger(ScrollResult.class);
private final Client client;
private final List<String> fields;
private final String queryHash; // used in log output only
private final long totalHits;
private String scrollId;
private int chunkId = 0;
public ScrollResult(Client client,
String originalQuery,
BytesReference builtQuery,
SearchResponse response, List<String> fields) {
super(originalQuery, builtQuery, response.getTook());
this.client = client;
this.fields = fields;
totalHits = response.getHits().totalHits();
scrollId = response.getScrollId();
final Md5Hash md5Hash = new Md5Hash(getOriginalQuery());
queryHash = md5Hash.toHex();
LOG.debug("[{}] Starting scroll request for query {}", queryHash, getOriginalQuery());
}
public ScrollChunk nextChunk() {
final SearchResponse search = client.prepareSearchScroll(scrollId)
.setScroll(TimeValue.timeValueMinutes(1))
.execute()
.actionGet();
final SearchHits hits = search.getHits();
if (hits.getHits().length == 0) {
// scroll exhausted
LOG.debug("[{}] Reached end of scroll results.", queryHash, getOriginalQuery());
return null;
}
LOG.debug("[{}] New scroll id {}", queryHash, search.getScrollId());
scrollId = search.getScrollId(); // save the id for the next request.
return new ScrollChunk(hits, fields, chunkId++);
}
public String getQueryHash() {
return queryHash;
}
public long totalHits() {
return totalHits;
}
public void cancel() {
final ClearScrollResponse clearScrollResponse = client.prepareClearScroll().addScrollId(scrollId).execute().actionGet();
LOG.debug("[{}] clearScroll for query successful: {}", queryHash, clearScrollResponse.isSucceeded());
}
public class ScrollChunk {
private final List<ResultMessage> resultMessages;
private List<String> fields;
private int chunkNumber;
public ScrollChunk(SearchHits hits, List<String> fields, int chunkId) {
this.fields = fields;
this.chunkNumber = chunkId;
resultMessages = buildResults(hits);
}
public List<String> getFields() {
return fields;
}
public int getChunkNumber() {
return chunkNumber;
}
public boolean isFirstChunk() {
return getChunkNumber() == 0;
}
public List<ResultMessage> getMessages() {
return resultMessages;
}
}
}