Event Driven Architectures for Spring Developers

In this example, I will make the use of maxwell to raise an event when some records created/updated/delete and raised events will go to kafka and interested consumer will consume that event.

Maxwell's Daemon

This is Maxwell’s daemon, an application that reads MySQL binlogs and writes row updates as JSON to Kafka, Kinesis, or other streaming platforms. Maxwell has low operational overhead, requiring nothing but mysql and a place to write to. Its common use cases include ETL, cache building/expiring, metrics collection, search indexing and inter-service communication. Maxwell gives you some of the benefits of event sourcing without having to re-architect your entire platform.

Quick Start - Maxwell's Daemon

maxwell — user maxwell — password maxwell — producer=kafka — kafka.bootstrap.servers=localhost:9092 — kafka_topic=maxwell

593 [WARN] MaxwellConfig: maxwell mysql host not specified, defaulting to localhost

541731 [WARN] NetworkClient: [Producer clientId=producer-1] Error while fetching metadata with correlation id 8 : {maxwell=LEADER_NOT_AVAILABLE}

Source Code: https://github.com/javaHelper/Event-Driven-Architectures-for-Spring-Developers/blob/main/README.md

2022-08-22 15:12:37.389  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : === Rate: 1.0, KeyUSD
2022-08-22 15:12:37.389  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : Currencies now: {USD=1.0}
2022-08-22 15:21:07.411  INFO 11924 --- [currency1-0-C-1] org.apache.kafka.clients.NetworkClient   : [Consumer clientId=consumer-currency1-1, groupId=currency1] Node -1 disconnected.
2022-08-22 15:34:35.421  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : === Rate: 0.782, KeyGBP
2022-08-22 15:34:35.421  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : Currencies now: {GBP=0.782, USD=1.0}
2022-08-22 15:38:59.033  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : === Rate: 0.8, KeyEUR
2022-08-22 15:38:59.034  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : Currencies now: {EUR=0.8, GBP=0.782, USD=1.0}
2022-08-22 15:41:22.113  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : === Rate: null, KeyEUR
2022-08-22 15:41:22.121  INFO 11924 --- [currency1-0-C-1] com.example.consumer.KafkaConsumer       : Currencies now: {GBP=0.782, USD=1.0}