content: /*
   * 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.kafka.streams.integration;
  
  import org.apache.kafka.clients.consumer.ConsumerConfig;
  import org.apache.kafka.clients.producer.ProducerConfig;
  import org.apache.kafka.common.serialization.LongDeserializer;
  import org.apache.kafka.common.serialization.Serdes;
  import org.apache.kafka.common.utils.Utils;
  import org.apache.kafka.streams.KafkaStreams;
  import org.apache.kafka.streams.KeyValue;
  import org.apache.kafka.streams.StreamsBuilder;
  import org.apache.kafka.streams.StreamsConfig;
  import org.apache.kafka.streams.integration.utils.EmbeddedKafkaCluster;
  import org.apache.kafka.streams.integration.utils.IntegrationTestUtils;
  import org.apache.kafka.streams.processor.Cancellable;
  import org.apache.kafka.streams.processor.PunctuationType;
  import org.apache.kafka.streams.processor.api.Processor;
  import org.apache.kafka.streams.processor.api.ProcessorContext;
  import org.apache.kafka.streams.processor.api.Record;
  import org.apache.kafka.test.StreamsTestUtils;
  import org.apache.kafka.test.TestUtils;
  
  import org.junit.jupiter.api.AfterAll;
  import org.junit.jupiter.api.BeforeAll;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Tag;
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.Timeout;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  import java.time.Duration;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Properties;
  import java.util.Set;
  import java.util.concurrent.atomic.AtomicBoolean;
  import java.util.concurrent.atomic.AtomicInteger;
  import java.util.concurrent.atomic.AtomicReference;
  
  import static org.apache.kafka.common.utils.Utils.mkEntry;
  import static org.apache.kafka.common.utils.Utils.mkMap;
  import static org.apache.kafka.streams.integration.utils.IntegrationTestUtils.startApplicationAndWaitUntilRunning;
  import static org.hamcrest.CoreMatchers.equalTo;
  import static org.hamcrest.MatcherAssert.assertThat;
  
  @Tag("integration")
  @Timeout(600)
  public class RebalanceIntegrationTest {
      private static final Logger LOG = LoggerFactory.getLogger(RebalanceIntegrationTest.class);
      private static final int NUM_BROKERS = 3;
      private static final int MAX_POLL_INTERVAL_MS = 30_000;
  
      public static final EmbeddedKafkaCluster CLUSTER = new EmbeddedKafkaCluster(
          NUM_BROKERS,
          Utils.mkProperties(mkMap(
              mkEntry("auto.create.topics.enable", "true"),
              mkEntry("transaction.max.timeout.ms", "" + Integer.MAX_VALUE)
          ))
      );
  
      @BeforeAll
      public static void startCluster() throws IOException {
          CLUSTER.start();
      }
  
      @AfterAll
      public static void closeCluster() {
          CLUSTER.stop();
      }
  
  
      private String applicationId;
      private static final int NUM_TOPIC_PARTITIONS = 2;
      private static final String MULTI_PARTITION_INPUT_TOPIC = "multiPartitionInputTopic";
      private static final String SINGLE_PARTITION_OUTPUT_TOPIC = "singlePartitionOutputTopic";
  
      private static final AtomicInteger TEST_NUMBER = new AtomicInteger(0);
  
      @BeforeEach
      public void createTopics() throws Exception {
          applicationId = "appId-" + TEST_NUMBER.getAndIncrement();
          CLUSTER.deleteTopics(MULTI_PARTITION_INPUT_TOPIC, SINGLE_PARTITION_OUTPUT_TOPIC);
  
          CLUSTER.createTopics(SINGLE_PARTITION_OUTPUT_TOPIC);
          CLUSTER.createTopic(MULTI_PARTITION_INPUT_TOPIC, NUM_TOPIC_PARTITIONS, 1);
      }
  
      private void checkResultPerKey(final List<KeyValue<Long, Long>> result,
                                     final List<KeyValue<Long, Long>> expectedResult) {
          final Set<Long> allKeys = new HashSet<>();
          addAllKeys(allKeys, result);
          addAllKeys(allKeys, expectedResult);
  
          for (final Long key : allKeys) {
              assertThat("The records do not match what expected", getAllRecordPerKey(key, result), equalTo(getAllRecordPerKey(key, expectedResult)));
          }
      }
  
      private void addAllKeys(final Set<Long> allKeys, final List<KeyValue<Long, Long>> records) {
          for (final KeyValue<Long, Long> record : records) {
              allKeys.add(record.key);
          }
      }
  
      private List<KeyValue<Long, Long>> getAllRecordPerKey(final Long key, final List<KeyValue<Long, Long>> records) {
          final List<KeyValue<Long, Long>> recordsPerKey = new ArrayList<>(records.size());
  
          for (final KeyValue<Long, Long> record : records) {
              if (record.key.equals(key)) {
                  recordsPerKey.add(record);
              }
          }
  
          return recordsPerKey;
      }
  
      @Test
      public void shouldCommitAllTasksIfRevokedTaskTriggerPunctuation() throws Exception {
          final AtomicBoolean requestCommit = new AtomicBoolean(false);
  
          final StreamsBuilder builder = new StreamsBuilder();
          builder.<Long, Long>stream(MULTI_PARTITION_INPUT_TOPIC)
              .process(() -> new Processor<Long, Long, Long, Long>() {
                  ProcessorContext<Long, Long> context;
                  @Override
                  public void init(final ProcessorContext<Long, Long> context) {
                      this.context = context;
  
                      final AtomicReference<Cancellable> cancellable = new AtomicReference<>();
                      cancellable.set(context.schedule(
                          Duration.ofSeconds(1),
                          PunctuationType.WALL_CLOCK_TIME,
                          time -> {
                              context.forward(new Record<>(
                                  (context.taskId().partition() + 1) * 100L,
                                  -(context.taskId().partition() + 1L),
                                  context.currentSystemTimeMs()));
                              cancellable.get().cancel();
                          }
                      ));
                  }
  
                  @Override
  
                  public void process(final Record<Long, Long> record) {
                      context.forward(record.withValue(context.recordMetadata().get().offset()));
  
                      if (requestCommit.get()) {
                          context.commit();
                      }
                  }
              })
              .to(SINGLE_PARTITION_OUTPUT_TOPIC);
  
          final Properties properties = new Properties();
          properties.put(StreamsConfig.STATESTORE_CACHE_MAX_BYTES_CONFIG, 0);
          properties.put(StreamsConfig.COMMIT_INTERVAL_MS_CONFIG, Integer.MAX_VALUE);
          properties.put(StreamsConfig.consumerPrefix(ConsumerConfig.MAX_POLL_RECORDS_CONFIG), 1);
          properties.put(StreamsConfig.consumerPrefix(ConsumerConfig.METADATA_MAX_AGE_CONFIG), "1000");
          properties.put(StreamsConfig.consumerPrefix(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG), "earliest");
          properties.put(StreamsConfig.consumerPrefix(ConsumerConfig.SESSION_TIMEOUT_MS_CONFIG), MAX_POLL_INTERVAL_MS - 1);
          properties.put(StreamsConfig.consumerPrefix(ConsumerConfig.MAX_POLL_INTERVAL_MS_CONFIG), MAX_POLL_INTERVAL_MS);
          properties.put(StreamsConfig.producerPrefix(ProducerConfig.TRANSACTION_TIMEOUT_CONFIG), Integer.MAX_VALUE);
          properties.put(StreamsConfig.TASK_ASSIGNOR_CLASS_CONFIG, TestTaskAssignor.class.getName());
  
          final Properties config = StreamsTestUtils.getStreamsConfig(
              applicationId,
              CLUSTER.bootstrapServers(),
              Serdes.LongSerde.class.getName(),
              Serdes.LongSerde.class.getName(),
              properties
          );
  
          try (final KafkaStreams streams = new KafkaStreams(builder.build(), config)) {
              startApplicationAndWaitUntilRunning(streams);
  
              // PHASE 1:
              // produce single output record via punctuation (uncommitted) [this happens for both tasks]
              // StreamThread-1 now has a task with progress, and one task w/o progress
              final List<KeyValue<Long, Long>> expectedUncommittedResultBeforeRebalance = Arrays.asList(KeyValue.pair(100L, -1L), KeyValue.pair(200L, -2L));
              final List<KeyValue<Long, Long>> uncommittedRecordsBeforeRebalance = IntegrationTestUtils.waitUntilMinKeyValueRecordsReceived(
                  TestUtils.consumerConfig(CLUSTER.bootstrapServers(), LongDeserializer.class, LongDeserializer.class),
                  SINGLE_PARTITION_OUTPUT_TOPIC,
                  expectedUncommittedResultBeforeRebalance.size()
              );
              checkResultPerKey(uncommittedRecordsBeforeRebalance, expectedUncommittedResultBeforeRebalance);
  
              // PHASE 2:
              // add second thread, to trigger rebalance
              // both task should get committed
              streams.addStreamThread();
  
              final List<KeyValue<Long, Long>> expectedUncommittedResultAfterRebalance = Arrays.asList(KeyValue.pair(100L, -1L), KeyValue.pair(200L, -2L));
              final List<KeyValue<Long, Long>> uncommittedRecordsAfterRebalance = IntegrationTestUtils.waitUntilMinKeyValueRecordsReceived(
                  TestUtils.consumerConfig(CLUSTER.bootstrapServers(), LongDeserializer.class, LongDeserializer.class),
                  SINGLE_PARTITION_OUTPUT_TOPIC,
                  expectedUncommittedResultAfterRebalance.size()
              );
              checkResultPerKey(uncommittedRecordsAfterRebalance, expectedUncommittedResultAfterRebalance);
          }
      }
  }