1 package de.juplo.kafka;
3 import lombok.RequiredArgsConstructor;
4 import lombok.extern.slf4j.Slf4j;
5 import org.apache.kafka.clients.consumer.ConsumerRebalanceListener;
6 import org.apache.kafka.common.TopicPartition;
11 @RequiredArgsConstructor
13 public class ApplicationRebalanceListener implements ConsumerRebalanceListener
15 private final ApplicationRecordHandler recordHandler;
16 private final AdderResults adderResults;
17 private final StateRepository stateRepository;
18 private final String id;
20 private final Set<Integer> partitions = new HashSet<>();
23 public void onPartitionsAssigned(Collection<TopicPartition> partitions)
25 partitions.forEach(tp ->
27 Integer partition = tp.partition();
28 log.info("{} - adding partition: {}", id, partition);
29 this.partitions.add(partition);
30 StateDocument document =
32 .findById(Integer.toString(partition))
33 .orElse(new StateDocument(partition));
34 recordHandler.addPartition(partition, document.state);
35 for (String user : document.state.keySet())
38 "{} - Restored state for partition={}|user={}: {}",
42 document.state.get(user));
44 adderResults.addPartition(partition, document.results);
49 public void onPartitionsRevoked(Collection<TopicPartition> partitions)
51 partitions.forEach(tp ->
53 Integer partition = tp.partition();
54 log.info("{} - removing partition: {}", id, partition);
55 this.partitions.remove(partition);
56 Map<String, AdderResult> state = recordHandler.removePartition(partition);
57 for (String user : state.keySet())
60 "{} - Saved state for partition={}|user={}: {}",
66 Map<String, List<AdderResult>> results = adderResults.removePartition(partition);
67 stateRepository.save(new StateDocument(partition, state, results));