I want to implement Kafka producer which sends and receives Java Serialized Objects. I tried this:
Producer:
@Configuration
public class KafkaProducerConfig {
@Value(value = "${kafka.bootstrapAddress}")
private String bootstrapAddress;
@Bean
public ProducerFactory<String, SaleRequestFactory> saleRequestFactoryProducerFactory() {
Map<String, Object> configProps = new HashMap<>();
configProps.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapAddress);
configProps.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
configProps.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, SaleRequestFactorySerializer.class);
return new DefaultKafkaProducerFactory<>(configProps);
}
@Bean
public ProducerFactory<String, String> producerFactory() {
Map<String, Object> configProps = new HashMap<>();
configProps.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapAddress);
return new DefaultKafkaProducerFactory<>(configProps);
}
@Bean
public KafkaTemplate<String, SaleRequestFactory> saleRequestFactoryKafkaTemplate() {
return new KafkaTemplate<>(saleRequestFactoryProducerFactory());
}
@Bean
public KafkaTemplate<String, String> kafkaTemplate() {
return new KafkaTemplate<>(producerFactory());
}
}
Send object:
@Autowired
private KafkaTemplate<String, SaleRequestFactory> saleRequestFactoryKafkaTemplate;
private static String topic = "tp-sale";
private void perform(){
SaleRequestFactory obj = new SaleRequestFactory();
obj.setId(100);
ListenableFuture<SendResult<String, SaleRequestFactory>> send = saleRequestFactoryKafkaTemplate.send(topic, obj);
}
Consumer:
@EnableKafka
@Configuration
public class KafkaConsumerConfig {
@Value(value = "${kafka.bootstrapAddress}")
private String bootstrapAddress;
private String groupId = "test";
@Bean
public ConsumerFactory<String, SaleResponseFactory> consumerFactory() {
Map<String, Object> props = new HashMap<>();
props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapAddress);
props.put(ConsumerConfig.GROUP_ID_CONFIG, groupId);
props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, SaleResponseFactoryDeserializer.class);
return new DefaultKafkaConsumerFactory<>(props);
}
@Bean
public ConcurrentKafkaListenerContainerFactory<String, SaleResponseFactory> kafkaListenerContainerFactory() {
ConcurrentKafkaListenerContainerFactory<String, SaleResponseFactory> factory =
new ConcurrentKafkaListenerContainerFactory<>();
factory.setConsumerFactory(consumerFactory());
return factory;
}
}
Receive Object
@KafkaListener(topics = "tp-sale")
public SaleResponseFactory transactionElavonAuthorizeProcess(@Payload SaleRequestFactory tf, @Headers MessageHeaders headers) throws Exception {
System.out.println(tf.getId());
SaleResponseFactory resObj = new SaleResponseFactory();
resObj.setUnique_id("123123");
return resObj;
}
Custom objects
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder(toBuilder = true)
public class SaleRequestFactory implements Serializable{
private static final long serialVersionUID = 1744050117179344127L;
private int id;
}
public class SaleRequestFactorySerializer implements Serializable, Serializer<SaleRequestFactory> {
@Override
public byte[] serialize(String topic, SaleRequestFactory data) {
// convert data to byte[]
ByteArrayOutputStream out = new ByteArrayOutputStream();
try
{
ObjectOutputStream outputStream = new ObjectOutputStream(out);
outputStream.writeObject(data);
out.close();
}
catch (IOException e)
{
e.printStackTrace();
}
return out.toByteArray();
}
}
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder(toBuilder = true)
public class SaleResponseFactory implements Serializable{
private static final long serialVersionUID = 1744050117179344127L;
private String unique_id;
}
public class SaleResponseFactoryDeserializer implements Serializable, Deserializer<SaleResponseFactory> {
@Override
public SaleResponseFactory deserialize(String topic, byte[] data) {
// convert data to SaleResponseFactory
SaleResponseFactory saleResponseFactory = null;
try
{
ByteArrayInputStream bis = new ByteArrayInputStream(data);
ObjectInputStream in = new ObjectInputStream(bis);
saleResponseFactory = (SaleResponseFactory) in.readObject();
in.close();
}
catch (IOException | ClassNotFoundException e)
{
e.printStackTrace();
}
return saleResponseFactory;
}
}
When I try to send message I get error:
Caused by: org.apache.kafka.common.errors.SerializationException: Error deserializing key/value for partition tp-sale-0 at offset 0. If needed, please seek past the record to continue consumption.
Caused by: java.lang.ClassCastException: null
21:27:51.152 [org.springframework.kafka.KafkaListenerEndpointContainer#0-0-C-1] DEBUG KafkaMessageListenerContainer$ListenerConsumer[debug:296] - Commit list: {}
21:27:51.153 [org.springframework.kafka.KafkaListenerEndpointContainer#0-0-C-1] ERROR KafkaMessageListenerContainer$ListenerConsumer[error:149] - Consumer exception
java.lang.IllegalStateException: This error handler cannot process 'SerializationException's directly; please consider configuring an 'ErrorHandlingDeserializer' in the value and/or key deserializer
at org.springframework.kafka.listener.SeekUtils.seekOrRecover(SeekUtils.java:145)
at org.springframework.kafka.listener.SeekToCurrentErrorHandler.handle(SeekToCurrentErrorHandler.java:103)
at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.handleConsumerException(KafkaMessageListenerContainer.java:1265)
at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.run(KafkaMessageListenerContainer.java:1022)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.lang.Thread.run(Thread.java:835)
Caused by: org.apache.kafka.common.errors.SerializationException: Error deserializing key/value for partition tp-sale-0 at offset 0. If needed, please seek past the record to continue consumption.
Caused by: java.lang.ClassCastException: null
Do you know how I can fix this issue?
EDIT: I managed to implement these improvements:
Producer:
@Configuration
public class KafkaProducerConfig {
@Value(value = "${kafka.bootstrapAddress}")
private String bootstrapAddress;
@Bean
public ProducerFactory<String, SaleRequestFactory> saleRequestFactoryProducerFactory() {
Map<String, Object> configProps = new HashMap<>();
configProps.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapAddress);
configProps.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
configProps.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, SaleRequestFactorySerializer.class);
return new DefaultKafkaProducerFactory<>(configProps);
}
@Bean
public ProducerFactory<String, String> producerFactory() {
Map<String, Object> configProps = new HashMap<>();
configProps.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapAddress);
return new DefaultKafkaProducerFactory<>(configProps);
}
@Bean
public KafkaTemplate<String, SaleRequestFactory> saleRequestFactoryKafkaTemplate() {
return new KafkaTemplate<>(saleRequestFactoryProducerFactory());
}
@Bean
public KafkaTemplate<String, String> kafkaTemplate() {
return new KafkaTemplate<>(producerFactory());
}
}
Send object:
@Autowired
private KafkaTemplate<String, SaleRequestFactory> saleRequestFactoryKafkaTemplate;
private static String topic = "tp-sale";
private void perform(){
SaleRequestFactory obj = new SaleRequestFactory();
obj.setId(100);
ListenableFuture<SendResult<String, SaleRequestFactory>> send = saleRequestFactoryKafkaTemplate.send(topic, obj);
}
Consumer:
@EnableKafka
@Configuration
public class KafkaConsumerConfig {
@Value(value = "${kafka.bootstrapAddress}")
private String bootstrapAddress;
private String groupId = "test";
@Bean
public ConsumerFactory<String, SaleResponseFactory> consumerFactory() {
Map<String, Object> props = new HashMap<>();
props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapAddress);
props.put(ConsumerConfig.GROUP_ID_CONFIG, groupId);
props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, SaleResponseFactoryDeserializer.class);
return new DefaultKafkaConsumerFactory<>(props);
}
@Bean
public ConcurrentKafkaListenerContainerFactory<String, SaleResponseFactory> kafkaListenerContainerFactory() {
ConcurrentKafkaListenerContainerFactory<String, SaleResponseFactory> factory =
new ConcurrentKafkaListenerContainerFactory<>();
factory.setConsumerFactory(consumerFactory());
return factory;
}
}
Receive Object
@KafkaListener(topics = "tp-sale")
public SaleResponseFactory transactionElavonAuthorizeProcess(@Payload SaleRequestFactory tf, @Headers MessageHeaders headers) throws Exception {
System.out.println(tf.getId());
SaleResponseFactory resObj = new SaleResponseFactory();
resObj.setUnique_id("123123");
return resObj;
}
Custom objects
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder(toBuilder = true)
public class SaleRequestFactory implements Serializable{
private static final long serialVersionUID = 1744050117179344127L;
private int id;
}
public class SaleRequestFactorySerializer implements Serializable, Serializer<SaleRequestFactory> {
@Override
public byte[] serialize(String topic, SaleRequestFactory data) {
// convert data to byte[]
ByteArrayOutputStream out = new ByteArrayOutputStream();
try
{
ObjectOutputStream outputStream = new ObjectOutputStream(out);
outputStream.writeObject(data);
out.close();
}
catch (IOException e)
{
e.printStackTrace();
}
return out.toByteArray();
}
}
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder(toBuilder = true)
public class SaleResponseFactory implements Serializable{
private static final long serialVersionUID = 1744050117179344127L;
private String unique_id;
}
public class SaleResponseFactoryDeserializer implements Serializable, Deserializer<SaleResponseFactory> {
@Override
public SaleResponseFactory deserialize(String topic, byte[] data) {
// convert data to SaleResponseFactory
SaleResponseFactory saleResponseFactory = null;
try
{
ByteArrayInputStream bis = new ByteArrayInputStream(data);
ObjectInputStream in = new ObjectInputStream(bis);
saleResponseFactory = (SaleResponseFactory) in.readObject();
in.close();
}
catch (IOException | ClassNotFoundException e)
{
e.printStackTrace();
}
return saleResponseFactory;
}
}
When I send some message I get error:
13:03:53.675 [org.springframework.kafka.KafkaListenerEndpointContainer#0-0-C-1] DEBUG RecordMessagingMessageListenerAdapter[debug:296] - Listener method returned result [org.factory.SaleResponseFactory@69c400ab] - generating response message for it
13:03:53.675 [org.springframework.kafka.KafkaListenerEndpointContainer#0-0-C-1] DEBUG RecordMessagingMessageListenerAdapter[debug:296] - No replyTopic to handle the reply: org.factory.SaleResponseFactory@69c400ab
Do you know how I can return SaleResponseFactory
back to the original Producer class?
EDIT 2: I get this exception:
org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.kafka.listener.KafkaMessageListenerContainer<java.lang.String, org.engine.plugin.transactions.factory.SaleResponseFactory>' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1717)
Assuming you've correctly configured server side for request reply you can use ReplyingKafkaTemplate
to receive the reply message on the client side.
Something like
Replying Producer Config
@Configuration
@Import({KafkaProducerConfig.class, KafkaConsumerConfig.class})
public class ReplyingKafkaProducerConfig {
@Bean
public ReplyingKafkaTemplate<String, SaleRequestFactory, SaleResponseFactory> replyKafkaTemplate(ProducerFactory<String, SaleRequestFactory> producerFactory, ConcurrentKafkaListenerContainerFactory<String, SaleResponseFactory> factory) {
ConcurrentMessageListenerContainer<String, SaleResponseFactory> container = factory.createContainer("tp-sale");
container.getContainerProperties().setGroupId("tp-sale.reply");
return new ReplyingKafkaTemplate<>(producerFactory, container);
}
}
Replying Template
@Autowired
private ReplyingKafkaTemplate<String, SaleRequestFactory, SaleResponseFactory> requestReplyKafkaTemplate;
private static String topic = "tp-sale";
private void perform(){
SaleRequestFactory obj = new SaleRequestFactory();
obj.setId(100);
ProducerRecord<String, SaleRequestFactory> record = new ProducerRecord<>("tp-sale", obj);
RequestReplyFuture<String, SaleRequestFactory, SaleResponseFactory> replyFuture = requestReplyKafkaTemplate.sendAndReceive(record);
SendResult<String, SaleRequestFactory> sendResult = replyFuture.getSendFuture().get(10, TimeUnit.SECONDS);
ConsumerRecord<String, SaleResponseFactory> consumerRecord = replyFuture.get(10, TimeUnit.SECONDS);
}
Example borrowed from https://docs.spring.io/spring-kafka/reference/html/#replying-template