阿里云kafka使用springboot单个项目中同时消费不同topic

本来是个简单的问题，但是复杂了。

两个topic 消费方式不一样，一个使用过的是默认方式，不指定partition，另外一个，指定了特殊的partition。报错：

11:10:32.888 [org.springframework.kafka.KafkaListenerEndpointContainer#1-0-C-1] 
ERROR o.a.k.c.c.i.ConsumerCoordinator - 
[Consumer clientId=futures_deal_group-1302249340-0, groupId=deal_group] 
Offset commit failed on partition topic-depth-6 at offset 1535688270: The coordinator is not aware of this member

11:10:32.888 [org.springframework.kafka.KafkaListenerEndpointContainer#1-0-C-1] 
WARN  o.a.k.c.c.i.ConsumerCoordinator - 
[Consumer clientId=futures_deal_group-1302249340-0, groupId=deal_group] 
Asynchronous auto-commit of offsets {topic-depth-6=OffsetAndMetadata{offset=1535688270, metadata=''}} 
failed: Commit cannot be completed since the group has already rebalanced and assigned the partitions to another member. This means that the time between subsequent c
alls to poll() was longer than the configured max.poll.interval.ms,
which typically implies that the poll loop is spending too much time message processing. 
You can address this either by increasing the session timeout or by reducing the maximum size of batches returned in poll() with max.poll.records.

大意就是提交的 offer 不是这个topic的，coordinator 不是这个topic

首先，单独跑任意一个topic 都可以正常运行，并能提交offersize 位置。

猜测一下 KafkaListenerEndpointContainer  报的错，就从他入手呗

可惜，spring-boot 里面并没有这个文件

那先找相近的来看看。从这开始，找  ConcurrentKafkaListenerContainerFactory  这个类

public KafkaListenerContainerFactory<ConcurrentMessageListenerContainer<String, String>> kafkaListenerContainerFactory() {
        ConcurrentKafkaListenerContainerFactory<String, String> factory = new ConcurrentKafkaListenerContainerFactory<>();
        factory.setConsumerFactory(new DefaultKafkaConsumerFactory<>(tickerConsumerConfigs()));
        factory.setConcurrency(1);
        factory.setBatchListener(true);
        factory.getContainerProperties().setPollTimeout(1500);
        return factory;
    }

找到父类  AbstractKafkaListenerContainerFactory，这里用到了 endpoint

public C createListenerContainer(KafkaListenerEndpoint endpoint) {
    C instance = createContainerInstance(endpoint);

    if (endpoint.getId() != null) {
      instance.setBeanName(endpoint.getId());
    }
    if (endpoint instanceof AbstractKafkaListenerEndpoint) {
      configureEndpoint((AbstractKafkaListenerEndpoint<K, V>) endpoint);
    }

    endpoint.setupListenerContainer(instance, this.messageConverter);
    initializeContainer(instance, endpoint);

    return instance;
  }

继续找，发现 KafkaListenerEndpoint 中有这样的说明，endpoint 的ID 在 factory 里面有用于区分其他的listener

public interface KafkaListenerEndpoint {

  /**
   * Return the id of this endpoint.
   * @return the id of this endpoint. The id can be further qualified
   * when the endpoint is resolved against its actual listener
   * container.
   * @see KafkaListenerContainerFactory#createListenerContainer
   */
  String getId();

  /**
   * Return the groupId of this endpoint - if present, overrides the
   * {@code group.id} property of the consumer factory.
   * @return the group id; may be null.
   * @since 1.3
   */
  String getGroupId();

对于未知的错误是不是我们的两个topic 都用 KafkaListenerEndpointContainer  一个而导致的问题，加上 id 

同时考虑  开始多个线程，试试能否解决

线程id 变了，还有问题。

继续寻找，在  org.springframework.kafka.listener.ConcurrentMessageListenerContainer  发现

for (int i = 0; i < this.concurrency; i++) {
        KafkaMessageListenerContainer<K, V> container;
        if (topicPartitions == null) {
          container = new KafkaMessageListenerContainer<>(this, this.consumerFactory, containerProperties);
        }
        else {
          container = new KafkaMessageListenerContainer<>(this, this.consumerFactory,
              containerProperties, partitionSubset(containerProperties, i));
        }
        String beanName = getBeanName();
        container.setBeanName((beanName != null ? beanName : "consumer") + "-" + i);
        if (getApplicationEventPublisher() != null) {
          container.setApplicationEventPublisher(getApplicationEventPublisher());
        }
        container.setClientIdSuffix("-" + i);
        container.setGenericErrorHandler(getGenericErrorHandler());
        container.setAfterRollbackProcessor(getAfterRollbackProcessor());
        container.setRecordInterceptor(getRecordInterceptor());
        container.setEmergencyStop(() -> {
          stop(() -> {
            // NOSONAR
          });
          publishContainerStoppedEvent();
        });
        if (isPaused()) {
          container.pause();
        }
        container.start();
        this.containers.add(container);
      }
    }

container 的生成跟clientId 有关？为每个 consumer 新增一个clientId 试试，依然报错

是不是果真如猜测的，是因为某个bean是公用的导致，提交offer 报错吗？

本地debug 时，ConcurrentKafkaListenerContainerFactory  、DefaultKafkaConsumerFactory  其实都不是一个类

在本地单独调试  topic2 时，服务器单独消费 topic1  居然又报错了，并且kafka 管理平台中观察topic1 的消费点位不变化了，与同时启动，2个consumer 的情况一样。

如此可以推断这个报错与 同时消费两个topic的 groupId 有关系。

修改代码 使用不同的 groupId，程序正常~~~~！！！