| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.apache.metamodel.elasticsearch.rest; |
| |
| import java.util.List; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import org.apache.metamodel.data.AbstractDataSet; |
| import org.apache.metamodel.data.DataSet; |
| import org.apache.metamodel.data.Row; |
| import org.apache.metamodel.query.SelectItem; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.google.gson.JsonArray; |
| import com.google.gson.JsonObject; |
| import com.google.gson.JsonPrimitive; |
| |
| import io.searchbox.client.JestClient; |
| import io.searchbox.client.JestResult; |
| import io.searchbox.core.SearchScroll; |
| |
| /** |
| * {@link DataSet} implementation for ElasticSearch |
| */ |
| final class JestElasticSearchDataSet extends AbstractDataSet { |
| |
| private static final Logger logger = LoggerFactory.getLogger(JestElasticSearchDataSet.class); |
| |
| private final JestClient _client; |
| private final AtomicBoolean _closed; |
| |
| private JestResult _searchResponse; |
| private JsonObject _currentHit; |
| private int _hitIndex = 0; |
| |
| public JestElasticSearchDataSet(JestClient client, JestResult searchResponse, List<SelectItem> selectItems) { |
| super(selectItems); |
| _client = client; |
| _searchResponse = searchResponse; |
| _closed = new AtomicBoolean(false); |
| } |
| |
| |
| @Override |
| public void close() { |
| super.close(); |
| boolean closeNow = _closed.compareAndSet(true, false); |
| if (closeNow) { |
| final String scrollId = _searchResponse.getJsonObject().getAsJsonPrimitive("_scroll_id").getAsString(); |
| JestClientExecutor.execute(_client, new JestDeleteScroll.Builder(scrollId).build(), false); |
| } |
| } |
| |
| @Override |
| protected void finalize() throws Throwable { |
| super.finalize(); |
| if (!_closed.get()) { |
| logger.warn("finalize() invoked, but DataSet is not closed. Invoking close() on {}", this); |
| close(); |
| } |
| } |
| |
| @Override |
| public boolean next() { |
| final JsonArray hits = _searchResponse.getJsonObject().getAsJsonObject("hits").getAsJsonArray("hits"); |
| if (hits.size() == 0) { |
| // break condition for the scroll |
| _currentHit = null; |
| return false; |
| } |
| |
| if (_hitIndex < hits.size()) { |
| // pick the next hit within this search response |
| _currentHit = hits.get(_hitIndex).getAsJsonObject(); |
| _hitIndex++; |
| return true; |
| } |
| |
| final JsonPrimitive scrollId = _searchResponse.getJsonObject().getAsJsonPrimitive("_scroll_id"); |
| if (scrollId == null) { |
| // this search response is not scrollable - then it's the end. |
| _currentHit = null; |
| return false; |
| } |
| |
| // try to scroll to the next set of hits |
| final SearchScroll scroll = new SearchScroll.Builder(scrollId.getAsString(), ElasticSearchRestDataContext.TIMEOUT_SCROLL).build(); |
| |
| _searchResponse = JestClientExecutor.execute(_client, scroll); |
| |
| // start over (recursively) |
| _hitIndex = 0; |
| return next(); |
| } |
| |
| @Override |
| public Row getRow() { |
| if (_currentHit == null) { |
| return null; |
| } |
| |
| final JsonObject source = _currentHit.getAsJsonObject("_source"); |
| final String documentId = _currentHit.get("_id").getAsString(); |
| return JestElasticSearchUtils.createRow(source, documentId, getHeader()); |
| |
| } |
| } |