/**
* 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 com.alibaba.jstorm.transactional.state.task;
import static org.slf4j.LoggerFactory.getLogger;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import org.slf4j.Logger;
import com.alibaba.jstorm.client.ConfigExtension;
import com.alibaba.jstorm.transactional.state.KeyRangeState;
import com.alibaba.jstorm.transactional.state.TransactionState;
import com.alibaba.jstorm.utils.JStormUtils;
public class KeyRangeStateTaskInit implements ITaskStateInitOperator {
private static final Logger LOG = getLogger(KeyRangeStateTaskInit.class);
@Override
public Object getTaskInitState(Map conf, int currTaskId, Set<Integer> currComponentTasks, Map<Integer, TransactionState> prevComponentTaskStates) {
Map<Integer, String> currKeyRangeToCheckpoints = new HashMap<Integer, String>();
Map<Integer, String> prevKeyRangeToCheckpoints = getAllKeyRangeCheckpointPaths(prevComponentTaskStates.values());
int componentTaskNum = currComponentTasks.size();
int taskIndex = JStormUtils.getTaskIndex(currTaskId, currComponentTasks);
int prevKeyRangeNum = prevKeyRangeToCheckpoints.size();
int configKeyRangeNum = ConfigExtension.getKeyRangeNum(conf);
int currKeyRangeNum = JStormUtils.getScaleOutNum(configKeyRangeNum, componentTaskNum);
Collection<Integer> currKeyRanges = KeyRangeState.keyRangesByTaskIndex(currKeyRangeNum, componentTaskNum, taskIndex);
LOG.debug("currKeyRanges: {}, prevKeyRangeToCheckpoints : {}", currKeyRanges, prevKeyRangeToCheckpoints);
// Check if scale-out of key range happens
if (currKeyRangeNum > prevKeyRangeNum) {
// key range number increases by 2^n times by default
for (Integer keyRange : currKeyRanges) {
currKeyRangeToCheckpoints.put(keyRange, prevKeyRangeToCheckpoints.get(keyRange % prevKeyRangeNum));
}
} else {
for (Integer keyRange : currKeyRanges) {
currKeyRangeToCheckpoints.put(keyRange, prevKeyRangeToCheckpoints.get(keyRange));
}
}
return currKeyRangeToCheckpoints;
}
private Map<Integer, String> getAllKeyRangeCheckpointPaths(Collection<TransactionState> allStates) {
Map<Integer, String> keyRangeToCheckpoints = new HashMap<Integer, String>();
for (TransactionState state : allStates) {
Map<Integer, String> checkpoint = (Map<Integer, String>) state.getUserCheckpoint();
if (checkpoint != null)
keyRangeToCheckpoints.putAll(checkpoint);
}
return keyRangeToCheckpoints;
}
}