Question

我想知道spring-kafka中是否有某些选项可以将所有新消息都捕获到列表中。

例如，如果我正在监听Message对象，那么我想获取自上次民意调查以来的List<Message>。像这样：

@KafkaListener(poll-interval=1000, topics = "${kafka.topic}", containerFactory = "objectListListenerContainerFactory", )
public void messageListener(List<Message> messages) {
    log.info("Count of new messages since last poll : {}", messages.size());
}

我已经经历过Spring Kafka: Poll for new messages instead of being notified using `onMessage`。但是对我来说不是很有用。

Answer 1

使用普通的Spring Kafka，您可以使用XmlDocument xdoc = new XmlDocument("YourXmlString"); XmlNodeList xNodes = xdoc.GetElementsByTagName("Id"); string Wished = xNodes[0].InnerText;创建一个ConsumerFactory，然后您可以自己方便地从那里轮询记录。

还请注意，KafkaConsumer可以在任意时刻被暂停以停止轮询，但仍可以连接到消费者组。

在Spring Integration Kafka扩展中，有一个新的KafkaMessageListenerContainer用于此类任务：

KafkaMessageSource

我认为我们需要考虑在Spring for Apache Kafka参考手册https://docs.spring.io/spring-kafka/docs/current/reference/html/_spring_integration.html#si-kafka中对此文档进行记录。因此，随时可以在/** * Polled message source for kafka. Only one thread can poll for data (or * acknowledge a message) at a time. * <p> * NOTE: If the application acknowledges messages out of order, the acks * will be deferred until all messages prior to the offset are ack'd. * If multiple records are retrieved and an earlier offset is requeued, records * from the subsequent offsets will be redelivered - even if they were * processed successfully. Applications should therefore implement * idempotency. * * @param <K> the key type. * @param <V> the value type. * * @author Gary Russell * @author Mark Norkin * @author Artem Bilan * * @since 3.0.1 * */ public class KafkaMessageSource<K, V> extends AbstractMessageSource<Object> implements DisposableBean, Lifecycle {项目中提出一个问题来解决这一差距。

有没有一种方法可以使用spring-kafka进行Kafka轮询-检索新邮件列表？

1 个答案: