第 6 篇 : SpringBoot整合Kafka

	org.springframework.kafka
	spring-kafka
	2.8.1

放在spring下

kafka:
    bootstrap-servers: 192.168.109.160:9092,192.168.109.161:9092,192.168.109.162:9092
    producer:
      key-serializer: org.apache.kafka.common.serialization.StringSerializer
      value-serializer: org.apache.kafka.common.serialization.StringSerializer
      acks: all
    consumer:
      key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
      value-deserializer: org.apache.kafka.common.serialization.StringDeserializer

package com.hahashou.test.redis.service;

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


@Component
@Slf4j
public class KafkaConsumer {

    public static final String FIRST_TOPIC = "first-topic";
    public static final String SECOND_TOPIC = "second-topic";

    @KafkaListener(topics = FIRST_TOPIC, groupId = "first")
    public void firstTopicFirst1 (ConsumerRecord record) {
        log.info("First主题第1个消费者 : "+record.topic()+" : "+record.partition()+" : "+record.value());
    }

    @KafkaListener(topics = FIRST_TOPIC, groupId = "first")
    public void firstTopicFirst2 (ConsumerRecord record) {
        log.info("First主题第2个消费者 : "+record.topic()+" : "+record.partition()+" : "+record.value());
    }

    @KafkaListener(topics = SECOND_TOPIC, groupId = "first")
    public void secondTopicFirst1 (ConsumerRecord record) {
        log.info("Second主题第1个消费者 : "+record.topic()+" : "+record.partition()+" : "+record.value());
    }
}

package com.hahashou.test.redis.controller;

import com.hahashou.test.redis.service.KafkaConsumer;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.web.bind.annotation.*;

import javax.annotation.Resource;


@RestController
@RequestMapping("/kafka")
@Api(tags = "测试Kafka")
@Slf4j
public class TestKafkaController {

    @Resource
    private KafkaTemplate kafkaTemplate;

    @GetMapping("/send")
    @ApiOperation(value = "发送消息")
    public String send(@RequestParam Integer count) throws InterruptedException {
        for (int i = 0; i < count; i++) {
            kafkaTemplate.send(KafkaConsumer.FIRST_TOPIC, i+" for first-topic");
            Thread.sleep(500);
            kafkaTemplate.send(KafkaConsumer.SECOND_TOPIC, i+"for second-topic");
        }
        return "成功";
    }
}

消费日志

根据我看到的文档,以及对kafka的了解,推断一下 :

消费记录按时间有序first-topic的第一个消费者监听的是分区 0 和 1, 第二个消费者监听的分区是 2 和 3多个分区数据由一组消费者消费,只有一个成员肯定自己全消费咯确实是按照配置文件创建了 4 个分区,官方示例是8官方给出的生产配置示例,不建议自动创建topic,是因为分区数量和消费者数量最好是比例差不多,对等应该是比较好的。手动创建topic,至少有那么一瞬间是知道自己需要创建topic,以及topic的分区数量、备份数量,以便后续开发人员创建合适数量的消费者。消费者数量肯定是不能多余分区数量的(官方文档应该有说吗,我没看到),下面增加3个消费者,测试一下

消费日志

第3个消费者没有抢到任何分区,就是个摆设,项目重启,消费者对应分区会重新分配