0x00 概述
最近测试跟我说，某个应用消费不到交易的消息。登录到Kafka Broker看下了下日志，发现一直在报错：
java.lang.IllegalArgumentException: Magic v0 does not support record headers
at org.apache.kafka.common.record.MemoryRecordsBuilder.appendWithOffset(MemoryRecordsBuilder.java:385)
at org.apache.kafka.common.record.MemoryRecordsBuilder.append(MemoryRecordsBuilder.java:568)
at org.apache.kafka.common.record.AbstractRecords.convertRecordBatch(AbstractRecords.java:117)
at org.apache.kafka.common.record.AbstractRecords.downConvert(AbstractRecords.java:98)
at org.apache.kafka.common.record.FileRecords.downConvert(FileRecords.java:245)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1$$anonfun$apply$5.apply(KafkaApis.scala:523)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1$$anonfun$apply$5.apply(KafkaApis.scala:521)
at scala.Option.map(Option.scala:146)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1.apply(KafkaApis.scala:521)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1.apply(KafkaApis.scala:511)
at scala.Option.flatMap(Option.scala:171)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$convertedPartitionData$1(KafkaApis.scala:511)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$createResponse$2$1.apply(KafkaApis.scala:559)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$createResponse$2$1.apply(KafkaApis.scala:558)
at scala.collection.Iterator$class.foreach(Iterator.scala:891)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1334)
at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$createResponse$2(KafkaApis.scala:558)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$fetchResponseCallback$1$1.apply$mcVI$sp(KafkaApis.scala:579)
at kafka.server.ClientQuotaManager.recordAndThrottleOnQuotaViolation(ClientQuotaManager.scala:196)
at kafka.server.KafkaApis.sendResponseMaybeThrottle(KafkaApis.scala:2012)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$fetchResponseCallback$1(KafkaApis.scala:578)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$processResponseCallback$1$1.apply$mcVI$sp(KafkaApis.scala:598)
at kafka.server.ClientQuotaManager.recordAndThrottleOnQuotaViolation(ClientQuotaManager.scala:196)
at kafka.server.ClientQuotaManager.recordAndMaybeThrottle(ClientQuotaManager.scala:188)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$processResponseCallback$1(KafkaApis.scala:597)
at kafka.server.KafkaApis$$anonfun$handleFetchRequest$1.apply(KafkaApis.scala:614)
at kafka.server.KafkaApis$$anonfun$handleFetchRequest$1.apply(KafkaApis.scala:614)
at kafka.server.ReplicaManager.fetchMessages(ReplicaManager.scala:639)
at kafka.server.KafkaApis.handleFetchRequest(KafkaApis.scala:606)
at kafka.server.KafkaApis.handle(KafkaApis.scala:98)
at kafka.server.KafkaRequestHandler.run(KafkaRequestHandler.scala:66)
at java.lang.Thread.run(Thread.java:748)
问了下相关开发人员，发现最近有个版本需要在Kafka信息的Headers中增加LogId来做交易跟踪，结合错误信息中提示消费者Api版本太低，不支持header信息，导致出错，让开发人员去掉header后，消费者可以正常消费消息
0x01 模拟重现
1.1 Kafka版本：0.11.0
生产者代码:
写了个拦截器，为每条消息的header中添加LOG_ID
public class KafkaProducerInterceptor<K, V> implements ProducerInterceptor<K, V> {
@Override
public void configure(Map<String, ?> configs) {}
@Override
public void onAcknowledgement(RecordMetadata metadata, Exception exception) {}
@Override
public void close() {}
@Override
public ProducerRecord onSend(ProducerRecord<K, V> record) {
String uuid = UUID.randomUUID().toString();
record.headers().add("LOG_ID",uuid.getBytes());
return record;
}
}
public class App
{
public static void main( String[] args ) throws InterruptedException
{
Properties props = new Properties();
// broker地址
props.put("bootstrap.servers", "localhost:9092");
// 请求时候需要验证
props.put("acks", "all");
// 请求失败时候需要重试
props.put("retries", 1);
// 内存缓存区大小
props.put("buffer.memory", 33554432);
// 指定消息key序列化方式
props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
// 指定消息本身的序列化方式
props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
List<String> interceptors = new ArrayList<>();
interceptors.add("com.df.KafkaTest.KafkaProducerInterceptor");
props.put(ProducerConfig.INTERCEPTOR_CLASSES_CONFIG, interceptors);
Producer<String, String> producer = new KafkaProducer<>(props);
for (int i = 10; i < 20; i++)
try {
AccessInfo ai = new AccessInfo();
ai.setAccessId("123456");
ai.setAccessName("源码婆媳"+Integer.toString(i));
ai.setBusScope("01");
ai.setIconUrl("http://www.baidu.com");
ProducerRecord record = new ProducerRecord<>("testTopic",0,"H"+Integer.toString(i),JSON.toJSONString(ai));
producer.send(record).get();
} catch (ExecutionException e) {
e.printStackTrace();
}
System.out.println("Message sent successfully");
producer.close();
}
}
消费者代码
使用高版本Api的客户端：
public class KafkaConsumerAsync {
public static void main(String[] args) throws InterruptedException {
// 1、准备配置文件
String kafkas = "127.0.0.1:9092";
Properties props = new Properties();
//kafka连接信息
props.put("bootstrap.servers",kafkas);
//消费者组id
props.put("group.id", "testTopic-002");
//是否自动提交offset
props.put("enable.auto.commit", "false");
//在没有offset的情况下采取的拉取策略
props.put("auto.offset.reset", "earliest");
//自动提交时间间隔
props.put("auto.commit.interval.ms", "1000");
//设置一次fetch请求取得的数据最大为1k
props.put("fetch.max.bytes", "1024");
//key反序列化
props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
//value反序列化
props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
String topic = "testTopic";
// 2、创建KafkaConsumer
KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
// 3、订阅数据，不给定监听器
consumer.subscribe(Collections.singleton(topic));
try{
//最少处理100条
int minCommitSize = 100;
//定义计数器
int icount = 0;
// 4、获取数据
while (true) {
ConsumerRecords<String, String> records = consumer.poll(100);
for (ConsumerRecord<String, String> record : records) {
System.out.printf("topic = %s,partition = %d,offset = %d, key = %s, value = %s%n", record.topic(), record.partition(),record.offset(), record.key(), record.value());
icount++;
}
//在业务逻辑处理成功后提交offset
if(icount >= minCommitSize){
//满足最少消费100条,再进行异步提交
consumer.commitAsync(new OffsetCommitCallback() {
@Override public void onComplete(Map<TopicPartition, OffsetAndMetadata> offsets, Exception exception) {
if(exception == null){
System.out.println("commit success");
}else {
//提交失败，对应处理
System.out.println("commit failed");
}
}
});
//计数器归零
icount = 0 ;
}
}
}catch (Exception e){
e.printStackTrace();
}finally {
//关闭连接
consumer.close();
}
}
}
执行结果：
[28 10:20:08,923 INFO ] [main] internals.AbstractCoordinator - [Consumer clientId=consumer-1, groupId=testTopic-002] Discovered group coordinator xxxxx.com:9092 (id: 2147483647 rack: null)
[28 10:20:08,931 INFO ] [main] internals.ConsumerCoordinator - [Consumer clientId=consumer-1, groupId=testTopic-002] Revoking previously assigned partitions []
[28 10:20:08,931 INFO ] [main] internals.AbstractCoordinator - [Consumer clientId=consumer-1, groupId=testTopic-002] (Re-)joining group
[28 10:20:08,958 INFO ] [main] internals.AbstractCoordinator - [Consumer clientId=consumer-1, groupId=testTopic-002] Successfully joined group with generation 1
[28 10:20:08,960 INFO ] [main] internals.ConsumerCoordinator - [Consumer clientId=consumer-1, groupId=testTopic-002] Setting newly assigned partitions [testTopic-0]
[28 10:20:08,978 INFO ] [main] internals.Fetcher - [Consumer clientId=consumer-1, groupId=testTopic-002] Resetting offset for partition testTopic-0 to offset 0.
topic = testTopic,partition = 0,offset = 0, key = H10, value = {"accessId":"123456","accessName":"源码婆媳10","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 1, key = H11, value = {"accessId":"123456","accessName":"源码婆媳11","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 2, key = H12, value = {"accessId":"123456","accessName":"源码婆媳12","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 3, key = H13, value = {"accessId":"123456","accessName":"源码婆媳13","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 4, key = H14, value = {"accessId":"123456","accessName":"源码婆媳14","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 5, key = H15, value = {"accessId":"123456","accessName":"源码婆媳15","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 6, key = H16, value = {"accessId":"123456","accessName":"源码婆媳16","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 7, key = H17, value = {"accessId":"123456","accessName":"源码婆媳17","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 8, key = H18, value = {"accessId":"123456","accessName":"源码婆媳18","busScope":"01","iconUrl":"http://www.baidu.com"}
topic = testTopic,partition = 0,offset = 9, key = H19, value = {"accessId":"123456","accessName":"源码婆媳19","busScope":"01","iconUrl":"http://www.baidu.com"}
使用低版本（0.8.22）客户端代码
public class SimpleConsumerExample {
private static kafka.javaapi.consumer.ConsumerConnector consumer;
public static void consume() {
Properties props = new Properties();
// zookeeper 配置
props.put("zookeeper.connect", "127.0.0.1:2181");
// group 代表一个消费组
props.put("group.id", "jd-group");
// zk连接超时
props.put("zookeeper.session.timeout.ms", "4000");
props.put("zookeeper.sync.time.ms", "200");
props.put("auto.commit.interval.ms", "1000");
props.put("auto.offset.reset", "smallest");
// 序列化类
props.put("serializer.class", "kafka.serializer.StringEncoder");
ConsumerConfig config = new ConsumerConfig(props);
consumer = kafka.consumer.Consumer.createJavaConsumerConnector(config);
Map<String, Integer> topicCountMap = new HashMap<String, Integer>();
topicCountMap.put("testTopic", new Integer(1));
StringDecoder keyDecoder = new StringDecoder(new VerifiableProperties());
StringDecoder valueDecoder = new StringDecoder(new VerifiableProperties());
Map<String, List<KafkaStream<String, String>>> consumerMap = consumer.createMessageStreams(topicCountMap,
keyDecoder, valueDecoder);
KafkaStream<String, String> stream = consumerMap.get("testTopic").get(0);
ConsumerIterator<String, String> it = stream.iterator();
while (it.hasNext())
System.out.println(it.next().message());
}
public static void main(String[] args) {
consume();
}
}
消费者运行后，一直消费不到消息
[28 09:51:41,590 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Connected to xxxxxx.xx.com:9092 for producing [28 09:51:41,591 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Disconnecting from xxxxxx.xx.com:9092 [28 09:51:41,592 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] consumer.ConsumerFetcherManager - [ConsumerFetcherManager-1566957087042] Added fetcher for partitions ArrayBuffer([[testTopic,0], initOffset 0 to broker id:0,host:xxxxxx.xx.com,port:9092] ) [28 09:51:41,798 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Verifying properties [28 09:51:41,798 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property client.id is overridden to jd-group [28 09:51:41,798 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property metadata.broker.list is overridden to xxxxxx.xx.com:9092 [28 09:51:41,798 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property request.timeout.ms is overridden to 30000 [28 09:51:41,798 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] client.ClientUtils$ - Fetching metadata from broker id:0,host:xxxxxx.xx.com,port:9092 with correlation id 65 for 1 topic(s) Set(testTopic) [28 09:51:41,799 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Connected to xxxxxx.xx.com:9092 for producing [28 09:51:41,824 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Disconnecting from xxxxxx.xx.com:9092 [28 09:51:41,825 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] consumer.ConsumerFetcherManager - [ConsumerFetcherManager-1566957087042] Added fetcher for partitions ArrayBuffer([[testTopic,0], initOffset 0 to broker id:0,host:xxxxxx.xx.com,port:9092] ) [28 09:51:42,032 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Verifying properties [28 09:51:42,032 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property client.id is overridden to jd-group [28 09:51:42,032 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property metadata.broker.list is overridden to xxxxxx.xx.com:9092 [28 09:51:42,032 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property request.timeout.ms is overridden to 30000 [28 09:51:42,033 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] client.ClientUtils$ - Fetching metadata from broker id:0,host:xxxxxx.xx.com,port:9092 with correlation id 66 for 1 topic(s) Set(testTopic) [28 09:51:42,035 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Connected to xxxxxx.xx.com:9092 for producing [28 09:51:42,041 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Disconnecting from xxxxxx.xx.com:9092 [28 09:51:42,041 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] consumer.ConsumerFetcherManager - [ConsumerFetcherManager-1566957087042] Added fetcher for partitions ArrayBuffer([[testTopic,0], initOffset 0 to broker id:0,host:xxxxxx.xx.com,port:9092] ) [28 09:51:42,251 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Verifying properties [28 09:51:42,252 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property client.id is overridden to jd-group [28 09:51:42,252 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property metadata.broker.list is overridden to xxxxxx.xx.com:9092 [28 09:51:42,252 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] utils.VerifiableProperties - Property request.timeout.ms is overridden to 30000 [28 09:51:42,253 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] client.ClientUtils$ - Fetching metadata from broker id:0,host:xxxxxx.xx.com,port:9092 with correlation id 67 for 1 topic(s) Set(testTopic) [28 09:51:42,254 INFO ] [jd-group_xxxxxx-1566957086889-abf02be8-leader-finder-thread] producer.SyncProducer - Connected to xxxxxx.xx.com:9092 for producing
Kafka Broker的server.log一直在刷错误日志：
[2019-08-28 09:51:42,045] ERROR [KafkaApi-0] Error when handling request {replica_id=-1,max_wait_time=100,min_bytes=1,topics=[{topic=testTopic,partitions=[{partition=0,fetch_offset=0,max_bytes=1048576}]}]} (kafka.server.KafkaApis)
java.lang.IllegalArgumentException: Magic v0 does not support record headers
at org.apache.kafka.common.record.MemoryRecordsBuilder.appendWithOffset(MemoryRecordsBuilder.java:385)
at org.apache.kafka.common.record.MemoryRecordsBuilder.append(MemoryRecordsBuilder.java:568)
at org.apache.kafka.common.record.AbstractRecords.convertRecordBatch(AbstractRecords.java:117)
at org.apache.kafka.common.record.AbstractRecords.downConvert(AbstractRecords.java:98)
at org.apache.kafka.common.record.FileRecords.downConvert(FileRecords.java:245)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1$$anonfun$apply$5.apply(KafkaApis.scala:523)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1$$anonfun$apply$5.apply(KafkaApis.scala:521)
at scala.Option.map(Option.scala:146)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1.apply(KafkaApis.scala:521)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$convertedPartitionData$1$1.apply(KafkaApis.scala:511)
at scala.Option.flatMap(Option.scala:171)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$convertedPartitionData$1(KafkaApis.scala:511)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$createResponse$2$1.apply(KafkaApis.scala:559)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$createResponse$2$1.apply(KafkaApis.scala:558)
at scala.collection.Iterator$class.foreach(Iterator.scala:891)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1334)
at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$createResponse$2(KafkaApis.scala:558)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$fetchResponseCallback$1$1.apply$mcVI$sp(KafkaApis.scala:579)
at kafka.server.ClientQuotaManager.recordAndThrottleOnQuotaViolation(ClientQuotaManager.scala:196)
at kafka.server.KafkaApis.sendResponseMaybeThrottle(KafkaApis.scala:2012)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$fetchResponseCallback$1(KafkaApis.scala:578)
at kafka.server.KafkaApis$$anonfun$kafka$server$KafkaApis$$processResponseCallback$1$1.apply$mcVI$sp(KafkaApis.scala:598)
at kafka.server.ClientQuotaManager.recordAndThrottleOnQuotaViolation(ClientQuotaManager.scala:196)
at kafka.server.ClientQuotaManager.recordAndMaybeThrottle(ClientQuotaManager.scala:188)
at kafka.server.KafkaApis.kafka$server$KafkaApis$$processResponseCallback$1(KafkaApis.scala:597)
at kafka.server.KafkaApis$$anonfun$handleFetchRequest$1.apply(KafkaApis.scala:614)
at kafka.server.KafkaApis$$anonfun$handleFetchRequest$1.apply(KafkaApis.scala:614)
at kafka.server.ReplicaManager.fetchMessages(ReplicaManager.scala:639)
at kafka.server.KafkaApis.handleFetchRequest(KafkaApis.scala:606)
at kafka.server.KafkaApis.handle(KafkaApis.scala:98)
at kafka.server.KafkaRequestHandler.run(KafkaRequestHandler.scala:66)
at java.lang.Thread.run(Thread.java:748)
通过错误日志信息结合源码，我们发现，在Broker拉取到Kakfa消息后，调用fetchResponseCallback回调方法，创建返回信息时，会校验消费者Api版本，如果低于当前Broker版本与向下转换消息
def fetchResponseCallback(bandwidthThrottleTimeMs: Int) {
def createResponse(requestThrottleTimeMs: Int): RequestChannel.Response = {
val convertedData = new util.LinkedHashMap[TopicPartition, FetchResponse.PartitionData]
fetchedPartitionData.asScala.foreach { case (tp, partitionData) =>
convertedData.put(tp, convertedPartitionData(tp, partitionData))
}
val response = new FetchResponse(convertedData, 0)
val responseStruct = response.toStruct(versionId)
trace(s"Sending fetch response to client $clientId of ${responseStruct.sizeOf} bytes.")
response.responseData.asScala.foreach { case (topicPartition, data) =>
// record the bytes out metrics only when the response is being sent
brokerTopicStats.updateBytesOut(topicPartition.topic, fetchRequest.isFromFollower, data.records.sizeInBytes)
}
val responseSend = response.toSend(responseStruct, bandwidthThrottleTimeMs + requestThrottleTimeMs,
request.connectionId, request.header)
RequestChannel.Response(request, responseSend)
}
if (fetchRequest.isFromFollower)
sendResponseExemptThrottle(createResponse(0))
else
sendResponseMaybeThrottle(request, request.header.clientId, requestThrottleMs =>
requestChannel.sendResponse(createResponse(requestThrottleMs)))
}
def convertedPartitionData(tp: TopicPartition, data: FetchResponse.PartitionData) = {
replicaManager.getMagic(tp).flatMap { magic =>
val downConvertMagic = {
if (magic > RecordBatch.MAGIC_VALUE_V0 && versionId <= 1 && !data.records.hasCompatibleMagic(RecordBatch.MAGIC_VALUE_V0))
Some(RecordBatch.MAGIC_VALUE_V0)
else if (magic > RecordBatch.MAGIC_VALUE_V1 && versionId <= 3 && !data.records.hasCompatibleMagic(RecordBatch.MAGIC_VALUE_V1))
Some(RecordBatch.MAGIC_VALUE_V1)
else
None
}
downConvertMagic.map { magic =>
trace(s"Down converting records from partition $tp to message format version $magic for fetch request from $clientId")
//在这里会对消息进行向下转换
val converted = data.records.downConvert(magic, fetchRequest.fetchData.get(tp).fetchOffset)
new FetchResponse.PartitionData(data.error, data.highWatermark, FetchResponse.INVALID_LAST_STABLE_OFFSET,
data.logStartOffset, data.abortedTransactions, converted)
}
}.getOrElse(data)
}
对消息转换，最后会调用MemoryRecordsBuilder的appendWithOffset，在此方法中做一些调用，如果调用不通过就会抛出异常，Magic v0 does not support record headers就是在此方法中抛出的。因为Magic v0 和Magic v1版本的消息格式中，不支持header
private Long appendWithOffset(long offset, boolean isControlRecord, long timestamp, ByteBuffer key,
ByteBuffer value, Header[] headers) {
try {
if (isControlRecord != isControlBatch)
throw new IllegalArgumentException("Control records can only be appended to control batches");
if (lastOffset != null && offset <= lastOffset)
throw new IllegalArgumentException(String.format("Illegal offset %s following previous offset %s " +
"(Offsets must increase monotonically).", offset, lastOffset));
if (timestamp < 0 && timestamp != RecordBatch.NO_TIMESTAMP)
throw new IllegalArgumentException("Invalid negative timestamp " + timestamp);
if (magic < RecordBatch.MAGIC_VALUE_V2 && headers != null && headers.length > 0)
throw new IllegalArgumentException("Magic v" + magic + " does not support record headers");
if (baseTimestamp == null)
baseTimestamp = timestamp;
if (magic > RecordBatch.MAGIC_VALUE_V1) {
appendDefaultRecord(offset, timestamp, key, value, headers);
return null;
} else {
return appendLegacyRecord(offset, timestamp, key, value);
}
} catch (IOException e) {
throw new KafkaException("I/O exception when writing to the append stream, closing", e);
}
}
1.2 Broker的Kafka版本1.0
运行低版本消费者：[28 14:26:23,068 INFO ] [jd-group_xx-1566973572731-a5b3105a-leader-finder-thread] consumer.ConsumerFetcherManager - [ConsumerFetcherManager-1566973572960] Added fetcher for partitions ArrayBuffer([[testTopic,0], initOffset -1 to broker id:0,host:xx.xx.com,port:9092] )
{"accessId":"123456","accessName":"源码婆媳10","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳11","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳12","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳13","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳14","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳15","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳16","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳17","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳18","busScope":"01","iconUrl":"http://www.baidu.com"}
{"accessId":"123456","accessName":"源码婆媳19","busScope":"01","iconUrl":"http://www.baidu.com"}
很奇怪，怎么升级下Broker版本就可以正常消费消息了呢？不是说好的v0版本消息格式不支持header吗？
看了下1.0版本的源码，发现在做消息向下转换的时候调用的不是MemoryRecordsBuilder，而是RecordsUtil的convertRecordBatch，当发现v0或v1版本时，直接忽略header信息，这样消费者就能正常消息消息了
private static MemoryRecordsBuilder convertRecordBatch(byte magic, ByteBuffer buffer, RecordBatchAndRecords recordBatchAndRecords) {
RecordBatch batch = recordBatchAndRecords.batch;
final TimestampType timestampType = batch.timestampType();
long logAppendTime = timestampType == TimestampType.LOG_APPEND_TIME ? batch.maxTimestamp() : RecordBatch.NO_TIMESTAMP;
MemoryRecordsBuilder builder = MemoryRecords.builder(buffer, magic, batch.compressionType(),
timestampType, recordBatchAndRecords.baseOffset, logAppendTime);
for (Record record : recordBatchAndRecords.records) {
// Down-convert this record. Ignore headers when down-converting to V0 and V1 since they are not supported
if (magic > RecordBatch.MAGIC_VALUE_V1)
builder.append(record);
else
builder.appendWithOffset(record.offset(), record.timestamp(), record.key(), record.value());
}
builder.close();
return builder;
}
0x02 总结
通过之前的分析，解决上面的错误有三种方法
1）升级消费端Api版本，升级到新版本后，支持header
2）升级Broker版本，1.0以上版本，向下转换时，会忽略到header信息
3）最后一种方式，也很简单，那就是生产者不增加header信息。因为我们项目中LOG-ID暂时不是必须的，我们选择了此种方式，等消费者端版本全部升级之后，再添加header信息
0x03 转载
https://www.jianshu.com/p/80ca3ade8fb2
https://zhuanlan.zhihu.com/p/205676507?utm_source=wechat_session