如何在java程序中获取kafka消耗滞后

Question

我写了一个java程序来消耗来自kafka的消息.我想监视消耗滞后,如何通过java获取它？

顺便说一句,我使用:

<groupId>org.apache.kafka</groupId>
<artifactId>kafka_2.11</artifactId>
<version>0.10.1.1</version>

提前致谢.

Answer 1

如果您不想在项目中包含kafka(和scala)依赖项,可以使用下面的类.它仅使用kafka-clients依赖项.

import org.apache.kafka.clients.consumer.ConsumerConfig;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.clients.consumer.OffsetAndMetadata;
import org.apache.kafka.common.PartitionInfo;
import org.apache.kafka.common.TopicPartition;
import org.apache.kafka.common.serialization.StringDeserializer;

import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.BinaryOperator;
import java.util.stream.Collectors;

public class KafkaConsumerMonitor {

    public static class PartionOffsets {
        private long endOffset;
        private long currentOffset;
        private int partion;
        private String topic;

        public PartionOffsets(long endOffset, long currentOffset, int partion, String topic) {
            this.endOffset = endOffset;
            this.currentOffset = currentOffset;
            this.partion = partion;
            this.topic = topic;
        }

        public long getEndOffset() {
            return endOffset;
        }

        public long getCurrentOffset() {
            return currentOffset;
        }

        public int getPartion() {
            return partion;
        }

        public String getTopic() {
            return topic;
        }
    }

    private final String monitoringConsumerGroupID = "monitoring_consumer_" + UUID.randomUUID().toString();

    public Map<TopicPartition, PartionOffsets> getConsumerGroupOffsets(String host, String topic, String groupId) {
        Map<TopicPartition, Long> logEndOffset = getLogEndOffset(topic, host);


        KafkaConsumer consumer = createNewConsumer(groupId, host);

        BinaryOperator<PartionOffsets> mergeFunction = (a, b) -> {
            throw new IllegalStateException();
        };

        Map<TopicPartition, PartionOffsets> result = logEndOffset.entrySet()
                .stream()
                .collect(Collectors.toMap(
                        entry -> (entry.getKey()),
                        entry -> {
                            OffsetAndMetadata committed = consumer.committed(entry.getKey());
                            return new PartionOffsets(entry.getValue(), committed.offset(), entry.getKey().partition(), topic);
                        }, mergeFunction));


        return result;
    }

    public Map<TopicPartition, Long> getLogEndOffset(String topic, String host) {
        Map<TopicPartition, Long> endOffsets = new ConcurrentHashMap<>();
        KafkaConsumer<?, ?> consumer = createNewConsumer(monitoringConsumerGroupID, host);
        List<PartitionInfo> partitionInfoList = consumer.partitionsFor(topic);
        List<TopicPartition> topicPartitions = partitionInfoList.stream().map(pi -> new TopicPartition(topic, pi.partition())).collect(Collectors.toList());
        consumer.assign(topicPartitions);
        consumer.seekToEnd(topicPartitions);
        topicPartitions.forEach(topicPartition -> endOffsets.put(topicPartition, consumer.position(topicPartition)));
        consumer.close();
        return endOffsets;
    }

    private static KafkaConsumer<?, ?> createNewConsumer(String groupId, String host) {
        Properties properties = new Properties();
        properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, host);
        properties.put(ConsumerConfig.GROUP_ID_CONFIG, groupId);
        properties.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, "false");
        properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        return new KafkaConsumer<>(properties);
    }
}

Answer 2

我个人直接从我的消费者那里查询 jmx 信息。我只在 java 中使用，因此 JMX beanskafka.consumer:type=consumer-fetch-manager-metrics,client-id=*/records-lag-max是可用的。

如果 jolokia 在您的类路径中，您可以使用 GET 检索该值/jolokia/read/kafka.consumer:type=consumer-fetch-manager-metrics,client-id=*/records-lag-max并将所有结果收集到一处。

还有Burrow，它非常容易配置，但它有点过时（如果我没记错的话，在 0.10 中不起作用）。