package de.juplo.kafka;
+import lombok.Value;
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.WakeupException;
-import org.apache.kafka.common.serialization.BytesSerializer;
-import org.apache.kafka.common.serialization.LongSerializer;
-import org.apache.kafka.common.serialization.StringSerializer;
+import org.apache.kafka.common.serialization.*;
import org.apache.kafka.common.utils.Bytes;
-import org.junit.jupiter.api.MethodOrderer;
-import org.junit.jupiter.api.Order;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.TestMethodOrder;
+import org.junit.jupiter.api.*;
import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration;
+import org.springframework.boot.autoconfigure.kafka.KafkaProperties;
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.context.annotation.Primary;
+import org.springframework.kafka.listener.adapter.ConsumerRecordMetadata;
+import org.springframework.kafka.support.serializer.JsonSerializer;
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.time.LocalDateTime;
import java.util.*;
-import java.util.concurrent.ExecutorService;
import java.util.function.BiConsumer;
-import java.util.function.Consumer;
-import java.util.function.Function;
+import java.util.function.BiFunction;
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.assertThat;
+import static org.assertj.core.api.Assertions.*;
+import static org.awaitility.Awaitility.*;
-@SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
-@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
+@SpringJUnitConfig(
+ initializers = ConfigDataApplicationContextInitializer.class,
+ classes = {
+ EndlessConsumer.class,
+ KafkaAutoConfiguration.class,
+ ApplicationTests.Configuration.class })
@TestPropertySource(
properties = {
- "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
+ "spring.kafka.consumer.bootstrap-servers=${spring.embedded.kafka.brokers}",
+ "spring.kafka.producer.bootstrap-servers=${spring.embedded.kafka.brokers}",
"consumer.topic=" + TOPIC })
@EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
@Slf4j
public static final int PARTITIONS = 10;
- StringSerializer stringSerializer = new StringSerializer();
- LongSerializer longSerializer = new LongSerializer();
-
+ @Autowired
+ Serializer valueSerializer;
@Autowired
KafkaProducer<String, Bytes> kafkaProducer;
@Autowired
- KafkaConsumer<String, Long> kafkaConsumer;
+ KafkaConsumer<Bytes, Bytes> offsetConsumer;
+ @Autowired
+ ApplicationProperties applicationProperties;
+ @Autowired
+ KafkaProperties kafkaProperties;
@Autowired
- ApplicationProperties properties;
+ EndlessConsumer endlessConsumer;
@Autowired
- ExecutorService executor;
+ MessageHandler<ClientMessage> clientMessageHandler;
+ @Autowired
+ MessageHandler<Greeting> greetingsHandler;
+
+ Map<TopicPartition, Long> oldOffsets;
+ Map<TopicPartition, Long> newOffsets;
+ Set<Object> received;
+ /** Tests methods */
+
@Test
- @Order(1) // << The poistion pill is not skipped. Hence, this test must run first
void commitsCurrentOffsetsOnSuccess()
{
- send100Messages(i -> new Bytes(longSerializer.serialize(TOPIC, i)));
+ send100Messages((key, counter) -> serializeAsClientMessage(key, counter));
- Set<ConsumerRecord<String, Long>> received = new HashSet<>();
- Map<TopicPartition, Long> offsets = runEndlessConsumer(record ->
- {
- received.add(record);
- if (received.size() == 100)
- throw new WakeupException();
- });
+ await("100 records received")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> received.size() == 100);
+
+ await("Offsets committed")
+ .atMost(Duration.ofSeconds(10))
+ .untilAsserted(() ->
+ {
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+ });
- check(offsets);
+ assertThat(endlessConsumer.isRunning())
+ .describedAs("Consumer should still be running")
+ .isTrue();
}
+
@Test
- @Order(2)
- void commitsNoOffsetsOnError()
+ void mixedMessages()
{
- send100Messages(counter ->
+ send100Messages((key, counter) ->
+ counter%3 == 0
+ ? serializeAsGreeting(key)
+ : serializeAsClientMessage(key, counter));
+
+ await("100 records received")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> received.size() == 100);
+
+ await("Offsets committed")
+ .atMost(Duration.ofSeconds(10))
+ .untilAsserted(() ->
+ {
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+ });
+
+ assertThat(endlessConsumer.isRunning())
+ .describedAs("Consumer should still be running")
+ .isTrue();
+ }
+
+ @Test
+ void commitsCurrentOffsetsOnDeserializationError()
+ {
+ send100Messages((key, counter) ->
counter == 77
- ? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
- : new Bytes(longSerializer.serialize(TOPIC, counter)));
+ ? serializeString("BOOM!", "message")
+ : serializeAsClientMessage(key, counter));
- Map<TopicPartition, Long> oldOffsets = new HashMap<>();
- doForCurrentOffsets((tp, offset) -> oldOffsets.put(tp, offset -1));
- Map<TopicPartition, Long> newOffsets = runEndlessConsumer((record) -> {});
+ await("99 records received")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> received.size() == 99);
+
+ await("Offsets committed")
+ .atMost(Duration.ofSeconds(10))
+ .untilAsserted(() ->
+ {
+ // UNSCHÖN:
+ // Funktioniert nur, weil nach der Nachrichten, die den
+ // Deserialisierungs-Fehler auslöst noch valide Nachrichten
+ // gelesen werden.
+ // GRUND:
+ // Der MessageHandler sieht den Offset der Fehlerhaften
+ // Nachricht nicht!
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+ });
+
+ assertThat(endlessConsumer.isRunning())
+ .describedAs("Consumer should still be running")
+ .isTrue();
+ }
+
+ @Test
+ void commitsOffsetOnProgramLogicErrorFoo()
+ {
+ clientMessageHandler.testHandler = (clientMessage, metadata) ->
+ {
+ if (Integer.parseInt(clientMessage.message)%10 ==0)
+ throw new RuntimeException("BOOM: " + clientMessage.message + "%10 == 0");
+ };
- check(oldOffsets);
+ send100Messages((key, counter) -> serializeAsClientMessage(key, counter));
+
+ await("80 records received")
+ .atMost(Duration.ofSeconds(30))
+ .until(() -> received.size() == 100);
+
+ await("Offsets committed")
+ .atMost(Duration.ofSeconds(10))
+ .pollDelay(Duration.ofSeconds(1))
+ .untilAsserted(() ->
+ {
+ checkSeenOffsetsForProgress();
+ compareToCommitedOffsets(newOffsets);
+ });
+
+ assertThat(endlessConsumer.isRunning())
+ .describedAs("Consumer should still be running")
+ .isTrue();
+ }
+
+
+ /** Helper methods for the verification of expectations */
+
+ void compareToCommitedOffsets(Map<TopicPartition, Long> offsetsToCheck)
+ {
+ doForCurrentOffsets((tp, offset) ->
+ {
+ Long expected = offsetsToCheck.get(tp) + 1;
+ log.debug("TEST: Comparing the expected offset of {} for {} to {}", expected, tp, offset);
+ 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("TEST: Progress for {}: {} -> {}", tp, oldOffset, newOffset);
+ withProgress.add(tp);
+ }
+ });
+ log.debug("TEST: Offsets with progress: {}", withProgress);
+ 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)
+ {
+ offsetConsumer.assign(partitions());
+ partitions().forEach(tp -> consumer.accept(tp, offsetConsumer.position(tp)));
+ offsetConsumer.unsubscribe();
+ }
+
+ List<TopicPartition> partitions()
+ {
+ return
+ IntStream
+ .range(0, PARTITIONS)
+ .mapToObj(partition -> new TopicPartition(TOPIC, partition))
+ .collect(Collectors.toList());
}
- void send100Messages(Function<Long, Bytes> messageGenerator)
+ void send100Messages(BiFunction<Integer, Long, BytesAndType> recordGenerator)
{
long i = 0;
{
for (int key = 0; key < 10; key++)
{
- Bytes value = messageGenerator.apply(++i);
+ BytesAndType bat = recordGenerator.apply(key, ++i);
ProducerRecord<String, Bytes> record =
new ProducerRecord<>(
TOPIC,
partition,
Integer.toString(key%2),
- value);
+ bat.getValue());
+ record.headers().add("__TypeId__", bat.getType());
kafkaProducer.send(record, (metadata, e) ->
{
if (metadata != null)
{
log.debug(
- "{}|{} - {}={}",
+ "TEST: Sending partition={}, offset={} - {}={}",
metadata.partition(),
metadata.offset(),
record.key(),
else
{
log.warn(
- "Exception for {}={}: {}",
+ "TEST: Exception for {}={}: {}",
record.key(),
record.value(),
e.toString());
}
}
- Map<TopicPartition, Long> runEndlessConsumer(Consumer<ConsumerRecord<String, Long>> consumer)
+ BytesAndType serializeAsClientMessage(Integer key, Long value)
{
- Map<TopicPartition, Long> offsets = new HashMap<>();
- doForCurrentOffsets((tp, offset) -> offsets.put(tp, offset -1));
- Consumer<ConsumerRecord<String, Long>> captureOffset =
- record ->
- offsets.put(
- new TopicPartition(record.topic(), record.partition()),
- record.offset());
- EndlessConsumer<String, Long> endlessConsumer =
- new EndlessConsumer<>(
- executor,
- properties.getClientId(),
- properties.getTopic(),
- kafkaConsumer,
- captureOffset.andThen(consumer));
-
- endlessConsumer.run();
+ ClientMessage message = new ClientMessage();
+ message.setClient(key.toString());
+ message.setMessage(value.toString());
+ return new BytesAndType(serialize(message), "message");
+ }
- return offsets;
+ BytesAndType serializeAsGreeting(Integer key)
+ {
+ Greeting greeting = new Greeting();
+ greeting.setName(key.toString());
+ greeting.setWhen(LocalDateTime.now());
+ return new BytesAndType(serialize(greeting), "greeting");
}
- List<TopicPartition> partitions()
+ BytesAndType serializeString(String message, String messageType)
{
- return
- IntStream
- .range(0, PARTITIONS)
- .mapToObj(partition -> new TopicPartition(TOPIC, partition))
- .collect(Collectors.toList());
+ return new BytesAndType(new Bytes(message.getBytes()), messageType);
}
- void doForCurrentOffsets(BiConsumer<TopicPartition, Long> consumer)
+ Bytes serialize(Object message)
{
- kafkaConsumer.assign(partitions());
- partitions().forEach(tp -> consumer.accept(tp, kafkaConsumer.position(tp)));
- kafkaConsumer.unsubscribe();
+ return new Bytes(valueSerializer.serialize(TOPIC, message));
}
- void check(Map<TopicPartition, Long> offsets)
+
+ @BeforeEach
+ public void init()
{
+ clientMessageHandler.testHandler = (clientMessage, metadata) -> {};
+ greetingsHandler.testHandler = (greeting, metadata) -> {};
+
+ oldOffsets = new HashMap<>();
+ newOffsets = new HashMap<>();
+ received = new HashSet<>();
+
doForCurrentOffsets((tp, offset) ->
{
- Long expected = offsets.get(tp) + 1;
- log.debug("Checking, if the offset for {} is {}", tp, expected);
- assertThat(offset).isEqualTo(expected);
+ oldOffsets.put(tp, offset - 1);
+ newOffsets.put(tp, offset - 1);
});
+
+ BiConsumer<?, ConsumerRecordMetadata> captureOffsets =
+ (clientMessage, metadata) ->
+ {
+ received.add(clientMessage);
+ log.debug("TEST: Processing record #{}: {}", received.size(), clientMessage);
+ newOffsets.put(
+ new TopicPartition(metadata.topic(), metadata.partition()), metadata.offset());
+ };
+
+ clientMessageHandler.captureOffsets =
+ (BiConsumer<ClientMessage, ConsumerRecordMetadata>)captureOffsets;
+ greetingsHandler.captureOffsets =
+ (BiConsumer<Greeting, ConsumerRecordMetadata>)captureOffsets;
+
+ endlessConsumer.start();
}
+ @AfterEach
+ public void deinit()
+ {
+ try
+ {
+ endlessConsumer.stop();
+ }
+ catch (Exception e)
+ {
+ log.info("TEST: Exception while stopping the consumer: {}", e.toString());
+ }
+ }
+
+ public static class MessageHandler<T> implements BiConsumer<T, ConsumerRecordMetadata>
+ {
+ BiConsumer<T, ConsumerRecordMetadata> captureOffsets;
+ BiConsumer<T, ConsumerRecordMetadata> testHandler;
+
+
+ @Override
+ public void accept(T message, ConsumerRecordMetadata metadata)
+ {
+ captureOffsets
+ .andThen(testHandler)
+ .accept(message, metadata);
+ }
+ }
@TestConfiguration
@Import(ApplicationConfiguration.class)
public static class Configuration
{
+ @Primary
+ @Bean
+ public MessageHandler<ClientMessage> messageHandler()
+ {
+ return new MessageHandler<>();
+ }
+
+ @Primary
+ @Bean
+ public MessageHandler<Greeting> greetingsHandler()
+ {
+ return new MessageHandler<>();
+ }
+
+ @Bean
+ Serializer<ClientMessage> serializer()
+ {
+ return new JsonSerializer<>();
+ }
+
@Bean
- KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
+ KafkaProducer<String, Bytes> kafkaProducer(KafkaProperties properties)
{
Properties props = new Properties();
- props.put("bootstrap.servers", properties.getBootstrapServer());
+ props.put("bootstrap.servers", properties.getConsumer().getBootstrapServers());
props.put("linger.ms", 100);
props.put("key.serializer", StringSerializer.class.getName());
props.put("value.serializer", BytesSerializer.class.getName());
return new KafkaProducer<>(props);
}
+
+ @Bean
+ KafkaConsumer<Bytes, Bytes> offsetConsumer(KafkaProperties properties)
+ {
+ Properties props = new Properties();
+ props.put("bootstrap.servers", properties.getConsumer().getBootstrapServers());
+ props.put("client.id", "OFFSET-CONSUMER");
+ props.put("group.id", properties.getConsumer().getGroupId());
+ props.put("key.deserializer", BytesDeserializer.class.getName());
+ props.put("value.deserializer", BytesDeserializer.class.getName());
+
+ return new KafkaConsumer<>(props);
+ }
+ }
+
+
+ @Value
+ static class BytesAndType
+ {
+ private final Bytes value;
+ private final byte[] type;
+
+
+ BytesAndType(Bytes value, String type)
+ {
+ this.value = value;
+ this.type = type.getBytes();
+ }
}
}
projects / demos / kafka / training / blobdiff