kafka复习：（24）consume-transform-produce模式

package com.cisdi.dsp.modules.metaAnalysis.rest.kafka2023;import org.apache.kafka.clients.consumer.*;import org.apache.kafka.clients.producer.KafkaProducer;import org.apache.kafka.clients.producer.ProducerConfig;import org.apache.kafka.clients.producer.ProducerRecord;import org.apache.kafka.common.TopicPartition;import org.apache.kafka.common.errors.ProducerFencedException;import org.apache.kafka.common.serialization.StringDeserializer;import org.apache.kafka.common.serialization.StringSerializer;import java.time.Duration;import java.util.*;public class KafkaTest24 {    public static final String brokerList = "k8s-master:9092";    public static Properties getConsumerProperties() {        Properties props = new Properties();        props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, brokerList);        props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());        props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());        //必须配置手动提交        props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, false);        props.put(ConsumerConfig.GROUP_ID_CONFIG, "groupId");        return props;    }    public static Properties getProducerProperties() {        Properties props = new Properties();        props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, brokerList);        props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());        props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());        props.put(ProducerConfig.TRANSACTIONAL_ID_CONFIG, "transactionalId");        return props;    }    //先从source-topic消费，再往sink-topic生产    public static void main(String[] args) {        KafkaConsumer consumer = new KafkaConsumer<>(getConsumerProperties());        consumer.subscribe(Collections.singletonList("source-topic"));        KafkaProducer producer = new KafkaProducer<>(getProducerProperties());        //初始化事务        producer.initTransactions();        while (true) {            ConsumerRecords records = consumer.poll(Duration.ofMillis(1000));            if (!records.isEmpty()) {                Map offsets = new HashMap<>();                //开启事务                producer.beginTransaction();                try {                    for (TopicPartition partition : records.partitions()) {                        List> partitionRecords = records.records(partition);                        for (ConsumerRecord record : partitionRecords) {ProducerRecord producerRecord =        new ProducerRecord<>("sink-topic", record.key(), record.value());producer.send(producerRecord);System.out.println("sent :" + record.value());                        }                        long lastConsumedOffset = partitionRecords.get(partitionRecords.size() - 1).offset();                        offsets.put(partition, new OffsetAndMetadata(lastConsumedOffset + 1));                    }                    // 提交消费位移                    // consume-transform-produce模式，此处的group id 必须要配置成consumer 中配置的group id                    producer.sendOffsetsToTransaction(offsets, "groupId");                    producer.commitTransaction();                } catch (ProducerFencedException e) {                    producer.abortTransaction();                }            }        }    }}

来源地址：https://blog.csdn.net/amadeus_liu2/article/details/132578447