/**
* 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
*
* 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 storm.trident.spout;
import backtype.storm.Config;
import backtype.storm.task.TopologyContext;
import backtype.storm.topology.BasicOutputCollector;
import backtype.storm.topology.IBasicBolt;
import backtype.storm.topology.OutputFieldsDeclarer;
import storm.trident.topology.TransactionAttempt;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Tuple;
import backtype.storm.tuple.Values;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import storm.trident.topology.MasterBatchCoordinator;
import storm.trident.topology.state.RotatingTransactionalState;
import storm.trident.topology.state.TransactionalState;
public class TridentSpoutCoordinator implements IBasicBolt {
public static final Logger LOG = LoggerFactory.getLogger(TridentSpoutCoordinator.class);
private static final String META_DIR = "meta";
ITridentSpout _spout;
ITridentSpout.BatchCoordinator _coord;
RotatingTransactionalState _state;
TransactionalState _underlyingState;
String _id;
public TridentSpoutCoordinator(String id, ITridentSpout spout) {
_spout = spout;
_id = id;
}
@Override
public void prepare(Map conf, TopologyContext context) {
_coord = _spout.getCoordinator(_id, conf, context);
_underlyingState = TransactionalState.newCoordinatorState(conf, _id);
_state = new RotatingTransactionalState(_underlyingState, META_DIR);
}
@Override
public void execute(Tuple tuple, BasicOutputCollector collector) {
TransactionAttempt attempt = (TransactionAttempt) tuple.getValue(0);
if(tuple.getSourceStreamId().equals(MasterBatchCoordinator.SUCCESS_STREAM_ID)) {
_state.cleanupBefore(attempt.getTransactionId());
_coord.success(attempt.getTransactionId());
} else {
long txid = attempt.getTransactionId();
Object prevMeta = _state.getPreviousState(txid);
Object meta = _coord.initializeTransaction(txid, prevMeta, _state.getState(txid));
_state.overrideState(txid, meta);
collector.emit(MasterBatchCoordinator.BATCH_STREAM_ID, new Values(attempt, meta));
}
}
@Override
public void cleanup() {
_coord.close();
_underlyingState.close();
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declareStream(MasterBatchCoordinator.BATCH_STREAM_ID, new Fields("tx", "metadata"));
}
@Override
public Map<String, Object> getComponentConfiguration() {
Config ret = new Config();
ret.setMaxTaskParallelism(1);
return ret;
}
}