1 package de.juplo.kafka;
3 import lombok.RequiredArgsConstructor;
4 import lombok.extern.slf4j.Slf4j;
5 import org.apache.kafka.clients.consumer.Consumer;
6 import org.apache.kafka.clients.consumer.ConsumerRebalanceListener;
7 import org.apache.kafka.common.TopicPartition;
12 @RequiredArgsConstructor
14 public class ApplicationRebalanceListener implements ConsumerRebalanceListener
16 private final Consumer consumer;
17 private final ApplicationRecordHandler recordHandler;
18 private final AdderResults adderResults;
19 private final StateRepository stateRepository;
20 private final String id;
22 private final Set<Integer> partitions = new HashSet<>();
25 public void onPartitionsAssigned(Collection<TopicPartition> partitions)
27 partitions.forEach(tp ->
29 Integer partition = tp.partition();
30 log.info("{} - adding partition: {}", id, partition);
31 this.partitions.add(partition);
32 StateDocument document =
34 .findById(Integer.toString(partition))
35 .orElse(new StateDocument(partition));
36 recordHandler.addPartition(partition, document.state);
37 for (String user : document.state.keySet())
40 "{} - Restored state for partition={}|user={}: {}",
44 document.state.get(user));
46 adderResults.addPartition(partition, document.results);
51 public void onPartitionsRevoked(Collection<TopicPartition> partitions)
53 log.info("{} - Commiting offsets for all previously assigned partitions", id);
54 consumer.commitSync();
56 partitions.forEach(tp ->
58 Integer partition = tp.partition();
59 log.info("{} - removing partition: {}", id, partition);
60 this.partitions.remove(partition);
61 Map<String, AdderResult> state = recordHandler.removePartition(partition);
62 for (String user : state.keySet())
65 "{} - Saved state for partition={}|user={}: {}",
71 Map<String, List<AdderResult>> results = adderResults.removePartition(partition);
72 stateRepository.save(new StateDocument(partition, state, results));