I am developing an Apache Storm (v2.5.0) topology that reads events from a spout (BaseRichSpout), counts the number of events in tumbling windows (BaseWindowedBolt), and prints the count (BaseRichBolt). The topology works fine, but there are some out-of-order events in my dataset. The BaseWindowedBolt provides withLateTupleStream method to route late events to a separate stream. However, when I try to process late events, I get a serialization exception:
`Caused by: com.esotericsoftware.kryo.KryoException: java.lang.IllegalArgumentException: Class is not registered: org.apache.storm.shade.com.google.common.collect.SingletonImmutableBiMap
Note: To register this class use: kryo.register(org.apache.storm.shade.com.google.common.collect.SingletonImmutableBiMap.class);
Serialization trace:
defaultResources (org.apache.storm.task.WorkerTopologyContext)
context (org.apache.storm.tuple.TupleImpl)
at com.esotericsoftware.kryo.serializers.ObjectField.write(ObjectField.java:101) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.serializers.FieldSerializer.write(FieldSerializer.java:508) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.Kryo.writeObject(Kryo.java:575) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.serializers.ObjectField.write(ObjectField.java:79) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.serializers.FieldSerializer.write(FieldSerializer.java:508) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.Kryo.writeClassAndObject(Kryo.java:651) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.serializers.CollectionSerializer.write(CollectionSerializer.java:100) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.serializers.CollectionSerializer.write(CollectionSerializer.java:40) ~[kryo-4.0.2.jar:?]
at com.esotericsoftware.kryo.Kryo.writeObject(Kryo.java:557) ~[kryo-4.0.2.jar:?]
at org.apache.storm.serialization.KryoValuesSerializer.serializeInto(KryoValuesSerializer.java:38) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.serialization.KryoTupleSerializer.serialize(KryoTupleSerializer.java:40) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.daemon.worker.WorkerState.checkSerialize(WorkerState.java:613) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.ExecutorTransfer.tryTransferLocal(ExecutorTransfer.java:101) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.ExecutorTransfer.tryTransfer(ExecutorTransfer.java:66) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.LocalExecutor$1.tryTransfer(LocalExecutor.java:36) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.bolt.BoltOutputCollectorImpl.boltEmit(BoltOutputCollectorImpl.java:112) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.bolt.BoltOutputCollectorImpl.emit(BoltOutputCollectorImpl.java:65) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.task.OutputCollector.emit(OutputCollector.java:93) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.task.OutputCollector.emit(OutputCollector.java:93) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.task.OutputCollector.emit(OutputCollector.java:42) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.topology.WindowedBoltExecutor.execute(WindowedBoltExecutor.java:313) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.bolt.BoltExecutor.tupleActionFn(BoltExecutor.java:212) ~[storm-client-2.5.0.jar:2.5.0]
at org.apache.storm.executor.Executor.accept(Executor.java:294) ~[storm-client-2.5.0.jar:2.5.0]
... 6 more`
I have defined my topology as below:
public class TestTopology {
public static void main (String[] args) throws Exception {
Config config = new Config();
config.put(Config.TOPOLOGY_TESTING_ALWAYS_TRY_SERIALIZE, true);
config.registerSerialization(TupleImpl.class);
config.registerSerialization(Fields.class);
LocalCluster cluster = new LocalCluster();
try (LocalCluster.LocalTopology topology = cluster.submitTopology("testTopology", config, getTopology().createTopology())) {
Thread.sleep(50000);}
cluster.shutdown();
}
static TopologyBuilder getTopology(){
TopologyBuilder builder = new TopologyBuilder();
builder.setSpout("eventSpout", new LateEventSpout());
builder.setBolt("windowBolt", new WindowBolt().withTumblingWindow(BaseWindowedBolt.Duration.seconds(10)).
withTimestampField("time").
withLateTupleStream("lateEvents")).
shuffleGrouping("eventSpout");
builder.setBolt("latePrintBolt", new LatePrintBolt()).
shuffleGrouping("windowBolt", "lateEvents");
builder.setBolt("printBolt", new PrintBolt()).shuffleGrouping("windowBolt");
return builder;
}
}
Where LateEventSpout is
public class LateEventSpout extends BaseRichSpout {
private SpoutOutputCollector collector;
private List<Long> eventTimes;
private int currentTime = 0;
private int id = 1;
public LateEventSpout () {
eventTimes = new ArrayList<>();
for (int i = 1; i<= 61; i++) {
eventTimes.add(Instant.EPOCH.plusSeconds(i).toEpochMilli());
} // [epoch+1, epoch+2, .., epoch+61]
}
@Override
public void open(Map<String, Object> conf, TopologyContext context, SpoutOutputCollector collector) {
this.collector = collector;
}
@Override
public void nextTuple() {
int eventId = id++;
Long eventTime = eventTimes.get(currentTime++);
if (currentTime == eventTimes.size()){
currentTime = 0; // reset time to zero so we have OOO events
}
collector.emit(new Values(eventId, eventTime));
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declare(new Fields("id", "time"));
}
}
And WindowBolt is:
public class WindowBolt extends BaseWindowedBolt {
OutputCollector collector;
@Override
public void prepare(Map<String, Object> topoConf, TopologyContext context, OutputCollector collector){
this.collector = collector;
}
@Override
public void execute(TupleWindow inputWindow) {
int sum = 0;
for (Tuple event : inputWindow.get()){
sum++;
}
collector.emit(new Values(inputWindow.getStartTimestamp(), inputWindow.getEndTimestamp(), sum));
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declare(new Fields("start", "end", "sum"));
}
}
And PrintBolt just prints the windowBolt output. (LatePrintBolt is similar)
public class PrintBolt extends BaseRichBolt {
@Override
public void prepare(Map<String, Object> topoConf, TopologyContext context, OutputCollector collector) {
}
@Override
public void execute(Tuple input) {
System.out.println(String.format("Start: %d, End: %d, Sum:%d", input.getLongByField("start"), input.getLongByField("end"), input.getIntegerByField("sum")));
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
}
}
If I don't set the LatePrintBolt in TopologyBuilder, I get the correct results
Start: 0, End: 10000, Sum:10
Start: 10000, End: 20000, Sum:10
Start: 20000, End: 30000, Sum:10
Start: 30000, End: 40000, Sum:10
Start: 40000, End: 50000, Sum:10
Start: 50000, End: 60000, Sum:10
However, when I try to print lateEvents stream, I get the same output but on the first late event, I get the above-mentioned exception.
I have debugged the issue. When WindowedBoltExecutor receives a late tuple, it emits the late tuple but BoltOutputCollectorImpl rewraps it in a new Tuple. Now, this new tuple contains WorkerTopologyContext which is not serializable, hence, the error.
I would like to know how can I process the late tuples.