実践PubSubマイクロサービス / Implementation Pub Sub microservice

イベント駆動なPUB/SUBのマイクロサービスについてお話しています。
具体的なコードを追いながらマイクロサービスを連携させているかの開設がメインです。
こちらのは JJUG CCC 2023 Fall の講演用資料です。
ライブコードリーディング前提の資料です。そのため、ライブコードリーディングがないと理解が難しいかもしれません。

YouTube: https://www.youtube.com/watch?v=gejnwpvsWJE
Code: https://github.com/nrslib/pubsubdoc

# URL
YouTube: https://www.youtube.com/c/narusemi
HomePage: https://nrslib.com
Twitter: https://twitter.com/nrslib

Transcript

84. public record DocCreated( DocId docId, String body ) implements DocEvent { } public record Doc( DocId docId, String body ) implements EventDrivenAggregateRoot<DocEvent> { ... } public record DocCreate(DocId docId, String body) implements DocCommand { }
121. @Configuration public class AxonConfiguration { @Bean public CorrelationDataProvider processIdCorrelationDataProvider() { return new MultiCorrelationDataProvider<CommandMessage<?>>( List.of( new SimpleCorrelationDataProvider("processId"), new MessageOriginProvider() ) ); } }
123. axon: kafka: client-id: pubsubdoc-service-back producer: retries: 0 consumer: event-processor-mode: tracking properties: security.protocol: PLAINTEXT default-topic: pubsubdoc-service-topic bootstrap-servers: localhost:29092,localhost:29192,localhost:29292
124. application: kafka: topics: doc-service-topic, payment-service-topic, pubsubdoc-service-topic, user-service-topic @Configuration @ConditionalOnExpression("!${application.disable-kafka:false} and '${axon.kafka.consumer.event-processor-mode}' == 'trackin public class AxonKafkaConfiguration { @Value("${application.kafka.topics}") private List<String> topics; @Bean public StreamableKafkaMessageSource<String, byte[]> streamableKafkaMessageSource(...) { return StreamableKafkaMessageSource.<String, byte[]>builder() .topics(topics) .consumerFactory(kafkaConsumerFactory) .fetcher(kafkaFetcher) .messageConverter(kafkaMessageConverter) .bufferFactory ( () -> new SortedKafkaMessageBuffer<>( properties.getFetcher().getBufferSize() )
126. @Configuration @ConditionalOnExpression("!${application.disable-kafka:false} and '${axon.kafka.consumer.event-pr public class AxonKafkaTrackingConfiguration { @Autowired public void registerProcessor( EventProcessingConfigurer configurer, StreamableKafkaMessageSource<String, byte[]> streamableKafkaMessageSource) { var processorNames = List.of( DocProjection.class.getPackageName(), UserProjection.class.getPackageName() ); processorNames.forEach(it -> configurer.registerTrackingEventProcessor( it, c -> streamableKafkaMessageSource )); } }
127. axon: eventhandling: processors: "[com.example.service.processor]": initialSegmentCount: 3 eventProcessingConfiguration.eventProcessors() .map { it.value } .filter { it is TrackingEventProcessor }.forEach { val casted = it as TrackingEventProcessor casted.splitSegment(segmentId) }