springboot 使用 kafka

pom 文件添加依赖

    org.springframework.kafka
    spring-kafka

application.yml 文件添加配置

bootstrap-servers：是 broker 地址，如果是集群，则用逗号分隔

spring:
  kafka:
    bootstrap-servers: 192.168.140.xxx:xxxx,192.168.140.xxx:xxxx,192.168.140.xxx:xxxx

生产者

import com.njc.java.entity.api.resp.TestInfoRespDTO;
import com.njc.java.entity.base.NjcResponseEntity;
import com.njc.java.property.KafkaProperty;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;


@RestController
public class KafkaProducerController extends BaseController {

    @Autowired
    KafkaTemplate kafkaTemplate;

    @Autowired
    KafkaProperty kafkaProperty;

    
    @ApiOperation(value = "卡夫卡推送", notes = "卡夫卡推送")
    @PostMapping(value = "/kafka/{msg}")
    NjcResponseEntity sendKafka(@PathVariable("msg") String msg) {
        kafkaTemplate.send("topic", msg);
        return super.success("成功发送kafka", null);
    }
}

消费者

import lombok.extern.slf4j.Slf4j;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Component;
import java.util.Optional;


@Slf4j
@Component
public class KafkaConsumer {

    @KafkaListener(topics = "#{'${spring.kafka.topicDemo}'}", groupId = "a")
    public void ProductInsertEvent1(ConsumerRecord record) {
        Optional kafkaMessage = Optional.ofNullable(record.value());
        kafkaMessage.ifPresent(msg -> {
            log.info("KafkaConsumer1 kafka value:{}", msg);
        });
    }

    @KafkaListener(topics = "#{'${spring.kafka.topicDemo}'}", groupId = "b")
    public void ProductInsertEvent2(ConsumerRecord record) {
        Optional kafkaMessage = Optional.ofNullable(record.value());
        kafkaMessage.ifPresent(msg -> {
            log.info("KafkaConsumer2 kafka value:{}", msg);
        });
    }

}

相同 topic 如果不用 groupId 区分会报错
No group.id found in consumer config, container properties, or @KafkaListener annotation; a group.id is required when group management is used.