/*
* 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 org.apache.flink.streaming.connectors.kafka.testutils;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.checkpoint.ListCheckpointed;
import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;
import org.apache.flink.test.util.SuccessException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.BitSet;
import java.util.Collections;
import java.util.List;
public class ValidatingExactlyOnceSink extends RichSinkFunction<Integer> implements ListCheckpointed<Tuple2<Integer, BitSet>> {
private static final Logger LOG = LoggerFactory.getLogger(ValidatingExactlyOnceSink.class);
private static final long serialVersionUID = 1748426382527469932L;
private final int numElementsTotal;
private BitSet duplicateChecker = new BitSet(); // this is checkpointed
private int numElements; // this is checkpointed
public ValidatingExactlyOnceSink(int numElementsTotal) {
this.numElementsTotal = numElementsTotal;
}
@Override
public void invoke(Integer value) throws Exception {
numElements++;
if (duplicateChecker.get(value)) {
throw new Exception("Received a duplicate: " + value);
}
duplicateChecker.set(value);
if (numElements == numElementsTotal) {
// validate
if (duplicateChecker.cardinality() != numElementsTotal) {
throw new Exception("Duplicate checker has wrong cardinality");
}
else if (duplicateChecker.nextClearBit(0) != numElementsTotal) {
throw new Exception("Received sparse sequence");
}
else {
throw new SuccessException();
}
}
}
@Override
public List<Tuple2<Integer, BitSet>> snapshotState(long checkpointId, long timestamp) throws Exception {
LOG.info("Snapshot of counter " + numElements + " at checkpoint " + checkpointId);
return Collections.singletonList(new Tuple2<>(numElements, duplicateChecker));
}
@Override
public void restoreState(List<Tuple2<Integer, BitSet>> state) throws Exception {
if (state.isEmpty() || state.size() > 1) {
throw new RuntimeException("Test failed due to unexpected recovered state size " + state.size());
}
Tuple2<Integer, BitSet> s = state.get(0);
LOG.info("restoring num elements to {}", s.f0);
this.numElements = s.f0;
this.duplicateChecker = s.f1;
}
}