--- /dev/null
+package de.juplo.kafka;
+
+import lombok.extern.slf4j.Slf4j;
+import org.apache.kafka.clients.consumer.ConsumerRecord;
+import org.apache.kafka.clients.consumer.KafkaConsumer;
+import org.apache.kafka.clients.producer.KafkaProducer;
+import org.apache.kafka.clients.producer.ProducerRecord;
+import org.apache.kafka.common.TopicPartition;
+import org.apache.kafka.common.errors.RecordDeserializationException;
+import org.apache.kafka.common.serialization.*;
+import org.apache.kafka.common.utils.Bytes;
+import org.junit.jupiter.api.*;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.test.autoconfigure.data.mongo.AutoConfigureDataMongo;
+import org.springframework.boot.test.context.ConfigDataApplicationContextInitializer;
+import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Import;
+import org.springframework.kafka.test.context.EmbeddedKafka;
+import org.springframework.test.context.TestPropertySource;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
+
+import java.time.Duration;
+import java.util.*;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.function.BiConsumer;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import static de.juplo.kafka.ApplicationTests.PARTITIONS;
+import static de.juplo.kafka.ApplicationTests.TOPIC;
+import static org.assertj.core.api.Assertions.*;
+import static org.awaitility.Awaitility.*;
+
+
+@SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
+@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
+@TestPropertySource(
+ properties = {
+ "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
+ "consumer.topic=" + TOPIC,
+ "spring.mongodb.embedded.version=4.4.13" })
+@EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
+@EnableAutoConfiguration
+@AutoConfigureDataMongo
+@Slf4j
+class ApplicationTests
+{
+ public static final String TOPIC = "FOO";
+ public static final int PARTITIONS = 10;
+
+
+ StringSerializer stringSerializer = new StringSerializer();
+
+ @Autowired
+ Serializer valueSerializer;
+ @Autowired
+ KafkaProducer<String, Bytes> kafkaProducer;
+ @Autowired
+ KafkaConsumer<String, Long> kafkaConsumer;
+ @Autowired
+ PartitionStatisticsRepository partitionStatisticsRepository;
+ @Autowired
+ ApplicationProperties properties;
+ @Autowired
+ ExecutorService executor;
+ @Autowired
+ PartitionStatisticsRepository repository;
+
+ Consumer<ConsumerRecord<String, Long>> testHandler;
+ EndlessConsumer<String, Long> endlessConsumer;
+ Map<TopicPartition, Long> oldOffsets;
+ Map<TopicPartition, Long> newOffsets;
+ Set<ConsumerRecord<String, Long>> receivedRecords;
+
+
+ /** Tests methods */
+
+ @Test
+ @Order(1) // << The poistion pill is not skipped. Hence, this test must run first
+ void commitsCurrentOffsetsOnSuccess() throws ExecutionException, InterruptedException
+ {
+ send100Messages(i -> new Bytes(valueSerializer.serialize(TOPIC, i)));
+
+ await("100 records received")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> receivedRecords.size() >= 100);
+
+ await("Offsets committed")
+ .atMost(Duration.ofSeconds(10))
+ .untilAsserted(() ->
+ {
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+ });
+
+ assertThatExceptionOfType(IllegalStateException.class)
+ .isThrownBy(() -> endlessConsumer.exitStatus())
+ .describedAs("Consumer should still be running");
+ }
+
+ @Test
+ @Order(2)
+ void commitsOffsetOfErrorForReprocessingOnError()
+ {
+ send100Messages(counter ->
+ counter == 77
+ ? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
+ : new Bytes(valueSerializer.serialize(TOPIC, counter)));
+
+ await("Consumer failed")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> !endlessConsumer.running());
+
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+
+ endlessConsumer.start();
+ await("Consumer failed")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> !endlessConsumer.running());
+
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+ assertThat(receivedRecords.size())
+ .describedAs("Received not all sent events")
+ .isLessThan(100);
+
+ assertThatNoException()
+ .describedAs("Consumer should not be running")
+ .isThrownBy(() -> endlessConsumer.exitStatus());
+ assertThat(endlessConsumer.exitStatus())
+ .describedAs("Consumer should have exited abnormally")
+ .containsInstanceOf(RecordDeserializationException.class);
+ }
+
+
+ /** Helper methods for the verification of expectations */
+
+ void compareToCommitedOffsets(Map<TopicPartition, Long> offsetsToCheck)
+ {
+ doForCurrentOffsets((tp, offset) ->
+ {
+ Long expected = offsetsToCheck.get(tp) + 1;
+ log.debug("Checking, if the offset for {} is {}", tp, expected);
+ assertThat(offset)
+ .describedAs("Committed offset corresponds to the offset of the consumer")
+ .isEqualTo(expected);
+ });
+ }
+
+ void checkSeenOffsetsForProgress()
+ {
+ // Be sure, that some messages were consumed...!
+ Set<TopicPartition> withProgress = new HashSet<>();
+ partitions().forEach(tp ->
+ {
+ Long oldOffset = oldOffsets.get(tp);
+ Long newOffset = newOffsets.get(tp);
+ if (!oldOffset.equals(newOffset))
+ {
+ log.debug("Progress for {}: {} -> {}", tp, oldOffset, newOffset);
+ withProgress.add(tp);
+ }
+ });
+ assertThat(withProgress)
+ .describedAs("Some offsets must have changed, compared to the old offset-positions")
+ .isNotEmpty();
+ }
+
+
+ /** Helper methods for setting up and running the tests */
+
+ void doForCurrentOffsets(BiConsumer<TopicPartition, Long> consumer)
+ {
+ partitions().forEach(tp ->
+ {
+ String partition = Integer.toString(tp.partition());
+ Optional<Long> offset = partitionStatisticsRepository.findById(partition).map(document -> document.offset);
+ consumer.accept(tp, offset.orElse(0l));
+ });
+ }
+
+ List<TopicPartition> partitions()
+ {
+ return
+ IntStream
+ .range(0, PARTITIONS)
+ .mapToObj(partition -> new TopicPartition(TOPIC, partition))
+ .collect(Collectors.toList());
+ }
+
+
+ void send100Messages(Function<Long, Bytes> messageGenerator)
+ {
+ long i = 0;
+
+ for (int partition = 0; partition < 10; partition++)
+ {
+ for (int key = 0; key < 10; key++)
+ {
+ Bytes value = messageGenerator.apply(++i);
+
+ ProducerRecord<String, Bytes> record =
+ new ProducerRecord<>(
+ TOPIC,
+ partition,
+ Integer.toString(key%2),
+ value);
+
+ kafkaProducer.send(record, (metadata, e) ->
+ {
+ if (metadata != null)
+ {
+ log.debug(
+ "{}|{} - {}={}",
+ metadata.partition(),
+ metadata.offset(),
+ record.key(),
+ record.value());
+ }
+ else
+ {
+ log.warn(
+ "Exception for {}={}: {}",
+ record.key(),
+ record.value(),
+ e.toString());
+ }
+ });
+ }
+ }
+ }
+
+
+ @BeforeEach
+ public void init()
+ {
+ testHandler = record -> {} ;
+
+ oldOffsets = new HashMap<>();
+ newOffsets = new HashMap<>();
+ receivedRecords = new HashSet<>();
+
+ doForCurrentOffsets((tp, offset) ->
+ {
+ oldOffsets.put(tp, offset - 1);
+ newOffsets.put(tp, offset - 1);
+ });
+
+ Consumer<ConsumerRecord<String, Long>> captureOffsetAndExecuteTestHandler =
+ record ->
+ {
+ newOffsets.put(
+ new TopicPartition(record.topic(), record.partition()),
+ record.offset());
+ receivedRecords.add(record);
+ testHandler.accept(record);
+ };
+
+ endlessConsumer =
+ new EndlessConsumer<>(
+ executor,
+ repository,
+ properties.getClientId(),
+ properties.getTopic(),
+ kafkaConsumer,
+ captureOffsetAndExecuteTestHandler);
+
+ endlessConsumer.start();
+ }
+
+ @AfterEach
+ public void deinit()
+ {
+ try
+ {
+ endlessConsumer.stop();
+ }
+ catch (Exception e)
+ {
+ log.info("Exception while stopping the consumer: {}", e.toString());
+ }
+ }
+
+
+ @TestConfiguration
+ @Import(ApplicationConfiguration.class)
+ public static class Configuration
+ {
+ @Bean
+ Serializer<Long> serializer()
+ {
+ return new LongSerializer();
+ }
+
+ @Bean
+ KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
+ {
+ Properties props = new Properties();
+ props.put("bootstrap.servers", properties.getBootstrapServer());
+ props.put("linger.ms", 100);
+ props.put("key.serializer", StringSerializer.class.getName());
+ props.put("value.serializer", BytesSerializer.class.getName());
+
+ return new KafkaProducer<>(props);
+ }
+ }
+}
projects / demos / kafka / training / blobdiff