JarCastingkafka-protobuf-serde
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Serializer/Deserializer for Kafka to serialize/deserialize Protocol Buffers messages
Requirements
| Dependency | Version |
|---|---|
| Kafka | 2.X.X |
| Protobuf | 3.X.X |
| Java | 8+ |
Usage
Add the following to your Maven dependency list:
<dependency>
<groupId>com.github.daniel-shuy</groupId>
<artifactId>kafka-protobuf-serde</artifactId>
<version>2.2.0</version>
</dependency>
Override the protobuf.version property with the version of Protobuf you wish to use (WARNING: do not directly override the protobuf-java dependency version):
<properties>
<protobuf.version>3.13.0</protobuf.version>
</properties>
Optionally, you may also override the kafka-clients dependency version with the version of Kafka you wish to use:
<properties>
<kafka.version>2.3.1</kafka.version>
</properties>
Kafka Producer
Properties props = new Properties();
// props.put(..., ...);
Producer<String, MyValue> producer = new KafkaProducer<>(props,
new StringSerializer(),
new KafkaProtobufSerializer<>());
producer.send(new ProducerRecord<>("topic", new MyValue()));
Kafka Consumer
Properties props = new Properties();
// props.put(..., ...);
Consumer<String, MyValue> consumer = new KafkaConsumer<>(props,
new StringDeserializer(),
new KafkaProtobufDeserializer<>(MyValue.parser()));
consumer.subscribe(Collections.singleton("topic"));
ConsumerRecords<String, MyValue> records = consumer.poll(Duration.ofMillis(100));
records.forEach(record -> {
String key = record.key();
MyValue value = record.value();
// ...
});
Kafka Streams
Serde<String> stringSerde = Serdes.String();
Serde<MyValue> myValueSerde = new KafkaProtobufSerde<>(MyValue.parser());
Properties config = new Properties();
// config.put(..., ...);
StreamsBuilder builder = new StreamsBuilder();
KStream<String, MyValue> myValues = builder.stream("input_topic", Consumed.with(stringSerde, myValueSerde));
KStream<String, MyValue> filteredMyValues = myValues.filter((key, value) -> {
// ...
});
filteredMyValues.to("output_topic", Produced.with(stringSerde, myValueSerde));
Topology topology = builder.build();
KafkaStreams streams = new KafkaStreams(topology, config);
streams.setUncaughtExceptionHandler((thread, throwable) -> {
// ...
});
Runtime.getRuntime().addShutdownHook(new Thread(streams::close));
streams.start();
Spring for Apache Kafka (spring-kafka)
Kafka Producer
@Configuration
public class KafkaConfig {
@Bean
public ProducerFactory<String, MyValue> producerFactory() {
Map<String, Object> props = new HashMap<>();
// props.put(..., ...);
return new DefaultKafkaProducerFactory<>(producerProps,
new StringSerializer(),
new KafkaProtobufSerializer<>());
}
@Bean
public KafkaTemplate<String, MyValue> kafkaTemplate() {
return new KafkaTemplate(producerFactory());
}
}
Kafka Consumer
@Configuration
@EnableKafka
public class KafkaConfig {
@Bean
KafkaListenerContainerFactory<ConcurrentMessageListenerContainer<String, MyValue>>
kafkaListenerContainerFactory() {
ConcurrentKafkaListenerContainerFactory<Integer, String> factory =
new ConcurrentKafkaListenerContainerFactory<>();
factory.setConsumerFactory(consumerFactory());
return factory;
}
@Bean
public ConsumerFactory<String, MyValue> consumerFactory() {
Map<String, Object> props = new HashMap<>();
// props.put(..., ...);
return new DefaultKafkaConsumerFactory<>(props,
new StringDeserializer(),
new KafkaProtobufDeserializer<>(MyValue.parser()));
}
}
public class Listener {
@KafkaListener(id = "foo", topics = "annotated1")
public void listen1(String foo) {
// ...
}
}