前言
不知道大家有没有遇到这样的场景，就是一个项目中要消费多个kafka消息，不同的消费者消费指定kafka消息。遇到这种场景，我们可以通过kafka的提供的api进行配置即可。但很多时候我们会使用spring-kafka来简化开发，可是spring-kafka原生的配置项并没提供多个kafka配置，因此本文就来聊聊如何将spring-kafka进行改造，使之能支持多个kafka配置
正文
代码语言：java复制1、通过 @ConfigurationProperties指定KafkaProperties前缀
@Primary
@ConfigurationProperties(prefix = "lybgeek.kafka.one")
@Bean
public KafkaProperties oneKafkaProperties(){
return new KafkaProperties();
}如果有多个就配置多个，形如
代码语言：java复制 @ConfigurationProperties(prefix = "lybgeek.kafka.two")
@Bean
public KafkaProperties twoKafkaProperties(){
return new KafkaProperties();
}
@ConfigurationProperties(prefix = "lybgeek.kafka.three")
@Bean
public KafkaProperties threeKafkaProperties(){
return new KafkaProperties();
}代码语言：java复制2、配置消费者工厂，消费者工厂绑定对应的KafkaProperties
@Bean
public ConsumerFactory twoConsumerFactory(@Autowired @Qualifier("twoKafkaProperties") KafkaProperties twoKafkaProperties){
return new DefaultKafkaConsumerFactory(twoKafkaProperties.buildConsumerProperties());
}代码语言：java复制3、配置消费者监听器工厂，并绑定指定消费者工厂以及消费者配置
@Bean(MultiKafkaConstant.KAFKA_LISTENER_CONTAINER_FACTORY_TWO)
public KafkaListenerContainerFactory twoKafkaListenerContainerFactory(@Autowired @Qualifier("twoKafkaProperties") KafkaProperties twoKafkaProperties, @Autowired @Qualifier("twoConsumerFactory") ConsumerFactory twoConsumerFactory) {
ConcurrentKafkaListenerContainerFactory factory = new ConcurrentKafkaListenerContainerFactory();
factory.setConsumerFactory(twoConsumerFactory);
factory.setConcurrency(ObjectUtil.isEmpty(twoKafkaProperties.getListener().getConcurrency()) ? Runtime.getRuntime().availableProcessors() : twoKafkaProperties.getListener().getConcurrency());
factory.getContainerProperties().setAckMode(ObjectUtil.isEmpty(twoKafkaProperties.getListener().getAckMode()) ? ContainerProperties.AckMode.MANUAL:twoKafkaProperties.getListener().getAckMode());
return factory;
}完整的配置示例如下
代码语言：java复制@Configuration
@EnableConfigurationProperties(MultiKafkaComsumeProperties.class)
public class OneKafkaComsumeAutoConfiguration {
@Bean(MultiKafkaConstant.KAFKA_LISTENER_CONTAINER_FACTORY_ONE)
public KafkaListenerContainerFactory oneKafkaListenerContainerFactory(@Autowired @Qualifier("oneKafkaProperties") KafkaProperties oneKafkaProperties, @Autowired @Qualifier("oneConsumerFactory") ConsumerFactory oneConsumerFactory) {
ConcurrentKafkaListenerContainerFactory factory = new ConcurrentKafkaListenerContainerFactory();
factory.setConsumerFactory(oneConsumerFactory);
factory.setConcurrency(ObjectUtil.isEmpty(oneKafkaProperties.getListener().getConcurrency()) ? Runtime.getRuntime().availableProcessors() : oneKafkaProperties.getListener().getConcurrency());
factory.getContainerProperties().setAckMode(ObjectUtil.isEmpty(oneKafkaProperties.getListener().getAckMode()) ? ContainerProperties.AckMode.MANUAL:oneKafkaProperties.getListener().getAckMode());
return factory;
}
@Primary
@Bean
public ConsumerFactory oneConsumerFactory(@Autowired @Qualifier("oneKafkaProperties") KafkaProperties oneKafkaProperties){
return new DefaultKafkaConsumerFactory(oneKafkaProperties.buildConsumerProperties());
}
@Primary
@ConfigurationProperties(prefix = "lybgeek.kafka.one")
@Bean
public KafkaProperties oneKafkaProperties(){
return new KafkaProperties();
}
}那个 @Primary要指定一下，不然启动会因为存在多个KafkaProperties,而导致kafka的自动装配不懂要选哪个而报错
代码语言：java复制@Configuration
@ConditionalOnClass(KafkaTemplate.class)
@EnableConfigurationProperties(KafkaProperties.class)
@Import({ KafkaAnnotationDrivenConfiguration.class, KafkaStreamsAnnotationDrivenConfiguration.class })
public class KafkaAutoConfiguration {
private final KafkaProperties properties;
private final RecordMessageConverter messageConverter;
public KafkaAutoConfiguration(KafkaProperties properties, ObjectProvider<RecordMessageConverter> messageConverter) {
this.properties = properties;
this.messageConverter = messageConverter.getIfUnique();
}
@Bean
@ConditionalOnMissingBean(KafkaTemplate.class)
public KafkaTemplate<?, ?> kafkaTemplate(ProducerFactory<Object, Object> kafkaProducerFactory,
ProducerListener<Object, Object> kafkaProducerListener) {
KafkaTemplate<Object, Object> kafkaTemplate = new KafkaTemplate<>(kafkaProducerFactory);
if (this.messageConverter != null) {
kafkaTemplate.setMessageConverter(this.messageConverter);
}
kafkaTemplate.setProducerListener(kafkaProducerListener);
kafkaTemplate.setDefaultTopic(this.properties.getTemplate().getDefaultTopic());
return kafkaTemplate;
}
@Bean
@ConditionalOnMissingBean(ProducerListener.class)
public ProducerListener<Object, Object> kafkaProducerListener() {
return new LoggingProducerListener<>();
}
@Bean
@ConditionalOnMissingBean(ConsumerFactory.class)
public ConsumerFactory<?, ?> kafkaConsumerFactory() {
return new DefaultKafkaConsumerFactory<>(this.properties.buildConsumerProperties());
}
@Bean
@ConditionalOnMissingBean(ProducerFactory.class)
public ProducerFactory<?, ?> kafkaProducerFactory() {
DefaultKafkaProducerFactory<?, ?> factory = new DefaultKafkaProducerFactory<>(
this.properties.buildProducerProperties());
String transactionIdPrefix = this.properties.getProducer().getTransactionIdPrefix();
if (transactionIdPrefix != null) {
factory.setTransactionIdPrefix(transactionIdPrefix);
}
return factory;
}
@Bean
@ConditionalOnProperty(name = "spring.kafka.producer.transaction-id-prefix")
@ConditionalOnMissingBean
public KafkaTransactionManager<?, ?> kafkaTransactionManager(ProducerFactory<?, ?> producerFactory) {
return new KafkaTransactionManager<>(producerFactory);
}
@Bean
@ConditionalOnProperty(name = "spring.kafka.jaas.enabled")
@ConditionalOnMissingBean
public KafkaJaasLoginModuleInitializer kafkaJaasInitializer() throws IOException {
KafkaJaasLoginModuleInitializer jaas = new KafkaJaasLoginModuleInitializer();
Jaas jaasProperties = this.properties.getJaas();
if (jaasProperties.getControlFlag() != null) {
jaas.setControlFlag(jaasProperties.getControlFlag());
}
if (jaasProperties.getLoginModule() != null) {
jaas.setLoginModule(jaasProperties.getLoginModule());
}
jaas.setOptions(jaasProperties.getOptions());
return jaas;
}
@Bean
@ConditionalOnMissingBean
public KafkaAdmin kafkaAdmin() {
KafkaAdmin kafkaAdmin = new KafkaAdmin(this.properties.buildAdminProperties());
kafkaAdmin.setFatalIfBrokerNotAvailable(this.properties.getAdmin().isFailFast());
return kafkaAdmin;
}
}同项目使用多个kafka消费者示例
代码语言：java复制1、在项目的pom引入spring-kafka GAV
<dependency>
<groupId>org.springframework.kafka</groupId>
<artifactId>spring-kafka</artifactId>
</dependency>代码语言：java复制2、在项目的yml中配置如下内容
lybgeek:
kafka:
multi:
comsume-enabled: false
one:
producer:
# kafka生产者服务端地址
bootstrap-servers: ${KAFKA_PRODUCER_BOOTSTRAP_SERVER:10.1.4.71:32643}
# 生产者重试的次数
retries: ${KAFKA_PRODUCER_RETRIES:0}
# 每次批量发送的数据量
batch-size: ${KAFKA_PRODUCER_BATCH_SIZE:16384}
# 每次批量发送消息的缓冲区大小
buffer-memory: ${KAFKA_PRODUCER_BUFFER_MEMOEY:335554432}
# 指定消息key和消息体的编码方式
key-serializer: ${KAFKA_PRODUCER_KEY_SERIALIZER:org.apache.kafka.common.serialization.StringSerializer}
value-serializer: ${KAFKA_PRODUCER_KEY_SERIALIZER:org.apache.kafka.common.serialization.StringSerializer}
# acks=1 只要集群的首领节点收到消息，生产者就会收到一个来自服务器成功响应。
acks: ${KAFKA_PRODUCER_ACK:1}
consumer:
bootstrap-servers: ${KAFKA_ONE_CONSUMER_BOOTSTRAP_SERVER:10.1.4.71:32643}
# 在偏移量无效的情况下，消费者将从起始位置读取分区的记录
auto-offset-reset: ${KAFKA_ONE_CONSUMER_AUTO_OFFSET_RESET:earliest}
# 是否自动提交偏移量，默认值是true,为了避免出现重复数据和数据丢失，可以把它设置为false,然后手动提交偏移量
enable-auto-commit: ${KAFKA_ONE_CONSUMER_ENABLE_AUTO_COMMIT:false}
# 指定消息key和消息体的解码方式
key-deserializer: ${KAFKA_ONE_CONSUMER_KEY_DESERIALIZER:org.apache.kafka.common.serialization.StringDeserializer}
value-deserializer: ${KAFKA_ONE_CONSUMER_VALUE_DESERIALIZER:org.apache.kafka.common.serialization.StringDeserializer}
listener:
# 在侦听器容器中运行的线程数。
concurrency: ${KAFKA_ONE_CONSUMER_CONCURRENCY:1}
missing-topics-fatal: false
ack-mode: ${KAFKA_ONE_CONSUMER_ACK_MODE:manual}
two:
producer:
# kafka生产者服务端地址
bootstrap-servers: ${KAFKA_PRODUCER_BOOTSTRAP_SERVER:192.168.1.3:9202}
# 生产者重试的次数
retries: ${KAFKA_PRODUCER_RETRIES:0}
# 每次批量发送的数据量
batch-size: ${KAFKA_PRODUCER_BATCH_SIZE:16384}
# 每次批量发送消息的缓冲区大小
buffer-memory: ${KAFKA_PRODUCER_BUFFER_MEMOEY:335554432}
# 指定消息key和消息体的编码方式
key-serializer: ${KAFKA_PRODUCER_KEY_SERIALIZER:org.apache.kafka.common.serialization.StringSerializer}
value-serializer: ${KAFKA_PRODUCER_KEY_SERIALIZER:org.apache.kafka.common.serialization.StringSerializer}
# acks=1 只要集群的首领节点收到消息，生产者就会收到一个来自服务器成功响应。
acks: ${KAFKA_PRODUCER_ACK:1}
consumer:
bootstrap-servers: ${KAFKA_ONE_CONSUMER_BOOTSTRAP_SERVER:192.168.1.3:9202}
# 在偏移量无效的情况下，消费者将从起始位置读取分区的记录
auto-offset-reset: ${KAFKA_ONE_CONSUMER_AUTO_OFFSET_RESET:earliest}
# 是否自动提交偏移量，默认值是true,为了避免出现重复数据和数据丢失，可以把它设置为false,然后手动提交偏移量
enable-auto-commit: ${KAFKA_ONE_CONSUMER_ENABLE_AUTO_COMMIT:false}
# 指定消息key和消息体的解码方式
key-deserializer: ${KAFKA_ONE_CONSUMER_KEY_DESERIALIZER:org.apache.kafka.common.serialization.StringDeserializer}
value-deserializer: ${KAFKA_ONE_CONSUMER_VALUE_DESERIALIZER:org.apache.kafka.common.serialization.StringDeserializer}
listener:
# 在侦听器容器中运行的线程数。
concurrency: ${KAFKA_ONE_CONSUMER_CONCURRENCY:1}
missing-topics-fatal: false
ack-mode: ${KAFKA_ONE_CONSUMER_ACK_MODE:manual}
代码语言：java复制3、配置生产者
private KafkaTemplate kafkaTemplate;
@Override
public MqResp sendSync(MqReq mqReq) {
ListenableFuture<SendResult<String, String>> result = this.send(mqReq);
MqResp mqResp = this.buildMqResp(result);
return mqResp;
}这个KafkaTemplate绑定的就是@Primary配置的kafkaProperties
代码语言：java复制4、配置消费者监听,并绑定containerFactory
@LybGeekKafkaListener(id = "createUser",containerFactory = MultiKafkaConstant.KAFKA_LISTENER_CONTAINER_FACTORY_ONE,topics = Constant.USER_TOPIC)
public class UserComsumer extends BaseComusmeListener {
@Autowired
private UserService userService;
@Override
public boolean isRepeateConsume(KafkaComsumePayLoad kafkaComsumePayLoad) {
User user = JSON.parseObject(kafkaComsumePayLoad.getData(),User.class);
System.out.println("-----------------------");
return userService.isExistUserByUsername(user.getUsername());
}
@Override
public boolean doBiz(KafkaComsumePayLoad kafkaComsumerPayLoad) {
User user = JSON.parseObject(kafkaComsumerPayLoad.getData(),User.class);
System.out.println(user);
return userService.save(user);
}
}通过指定containerFactory ，来消费指定的kafka消息
代码语言：java复制5、测试
User user = User.builder().username("test")
.email("test@qq.com")
.fullname("test")
.mobile("1350000001")
.password("1234561")
.build();
userService.saveAndPush(user);发送消息，观察控制台输出
代码语言：java复制: messageKey:【null】，topic：【user-sync】存在重复消息数据-->【{"email":"test@qq.com","fullname":"test","mobile":"1350000000","password":"123456","username":"test"}】会出现这样，是因为数据库已经有这条记录了，刚好验证一下重复消费
总结
本文实现的核心其实就是通过注入多个kafkaProperties来实现多配置 ，不知道大家有没有发现，就是改造后的配置，配置消费者后，生产者仍然也要配置。因为如果不配置，走的就是kafkaProperties默认的配置信息，即为localhost。还有细心的朋友也许会发现我示例中的消费者监听使用的注解是@LybGeekKafkaListener，这个和 @KafkaListener实现的功能基本一致。因为本示例和之前的文章聊聊如何实现一个带幂等模板的kafka消费者监听是同份代码，就直接复用了
demo链接
https://github.com/lyb-geek/springboot-learning/tree/master/springboot-kafka-template
