Hi, I am attempting to create a Key/Value serializer for the Kafka table connector. I forked `KafkaTableSourceSinkFactoryBase`[1] and other relevant classes, updating the serializer.
First, I created `JsonRowKeyedSerializationSchema` which implements `KeyedSerializationSchema`[2], which is deprecated. The way it works is you provide a list of indices in your Row output that are the Key. This works successfully. When I tried migrating my `JsonRowKeyedSerializationSchema` to implement `KafkaSerializationSchema`[3], I get a `java.lang.AbstractMethodError` exception. Normally, this would me I'm using an old interface however all my Flink dependencies are version 1.9. I can not find this abstract `serialize()` function in the Flink codebase. Has anyone come across this before? When I print the method of my `JsonRowKeyedSerializationSchema` class, I do see the below which seems to be getting called by the FlinkKafkaProducer but I do not see it in `KafkaSerializationSchema`: public abstract org.apache.flink.kafka.shaded.org.apache.kafka.clients.producer.ProducerRecord org.apache.flink.streaming.connectors.kafka.KafkaSerializationSchema.serialize(java.lang.Object,java.lang.Long) java.lang.Object java.lang.Long *`JsonRowKeyedSerializationSchema` class* import org.apache.flink.streaming.connectors.kafka.KafkaSerializationSchema; import org.apache.flink.types.Row; import org.apache.kafka.clients.producer.ProducerRecord; public class JsonRowKeyedSerializationSchema implements KafkaSerializationSchema<Row> { // constructors and helpers @Override public ProducerRecord<byte[], byte[]> serialize(Row row, @Nullable Long aLong) { return new ProducerRecord<>("some_topic", serializeKey(row), serializeValue(row)); } } *Stacktrace:* Caused by: java.lang.AbstractMethodError: Method com/mypackage/flink/serialization/json/JsonRowKeyedSerializationSchema.serialize(Ljava/lang/Object;Ljava/lang/Long;)Lorg/apache/flink/kafka/shaded/org/apache/kafka/clients/producer/ProducerRecord; is abstract at com.mypackage.flink.serialization.json.JsonRowKeyedSerializationSchema.serialize(JsonRowKeyedSerializationSchema.java) at org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer.invoke(FlinkKafkaProducer.java:816) at org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer.invoke(FlinkKafkaProducer.java:98) at org.apache.flink.streaming.api.functions.sink.TwoPhaseCommitSinkFunction.invoke(TwoPhaseCommitSinkFunction.java:228) at org.apache.flink.streaming.api.operators.StreamSink.processElement(StreamSink.java:56) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.pushToOperator(OperatorChain.java:546) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.collect(OperatorChain.java:523) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.collect(OperatorChain.java:483) at org.apache.flink.streaming.api.operators.AbstractStreamOperator$CountingOutput.collect(AbstractStreamOperator.java:727) at org.apache.flink.streaming.api.operators.AbstractStreamOperator$CountingOutput.collect(AbstractStreamOperator.java:705) at org.apache.flink.streaming.api.operators.StreamMap.processElement(StreamMap.java:41) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.pushToOperator(OperatorChain.java:546) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.collect(OperatorChain.java:523) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.collect(OperatorChain.java:483) at org.apache.flink.streaming.api.operators.AbstractStreamOperator$CountingOutput.collect(AbstractStreamOperator.java:727) at org.apache.flink.streaming.api.operators.AbstractStreamOperator$CountingOutput.collect(AbstractStreamOperator.java:705) at org.apache.flink.streaming.api.operators.StreamMap.processElement(StreamMap.java:41) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.pushToOperator(OperatorChain.java:546) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.collect(OperatorChain.java:523) at org.apache.flink.streaming.runtime.tasks.OperatorChain$ChainingOutput.collect(OperatorChain.java:483) at org.apache.flink.streaming.api.operators.AbstractStreamOperator$CountingOutput.collect(AbstractStreamOperator.java:727) at org.apache.flink.streaming.api.operators.AbstractStreamOperator$CountingOutput.collect(AbstractStreamOperator.java:705) at org.apache.flink.streaming.api.operators.StreamSourceContexts$ManualWatermarkContext.processAndCollectWithTimestamp(StreamSourceContexts.java:310) at org.apache.flink.streaming.api.operators.StreamSourceContexts$WatermarkContext.collectWithTimestamp(StreamSourceContexts.java:409) at org.apache.flink.streaming.connectors.kafka.internals.AbstractFetcher.emitRecordWithTimestamp(AbstractFetcher.java:398) at org.apache.flink.streaming.connectors.kafka.internal.KafkaFetcher.emitRecord(KafkaFetcher.java:185) at org.apache.flink.streaming.connectors.kafka.internal.KafkaFetcher.runFetchLoop(KafkaFetcher.java:150) at org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumerBase.run(FlinkKafkaConsumerBase.java:715) at org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:100) at org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:63) at org.apache.flink.streaming.runtime.tasks.SourceStreamTask$LegacySourceFunctionThread.run(SourceStreamTask.java:202) [1] https://github.com/apache/flink/blob/release-1.9.0/flink-connectors/flink-connector-kafka-base/src/main/java/org/apache/flink/streaming/connectors/kafka/KafkaTableSourceSinkFactoryBase.java [2] https://github.com/apache/flink/blob/release-1.9.0/flink-connectors/flink-connector-kafka-base/src/main/java/org/apache/flink/streaming/util/serialization/KeyedSerializationSchema.java [3] https://github.com/apache/flink/blob/release-1.9.0/flink-connectors/flink-connector-kafka-base/src/main/java/org/apache/flink/streaming/connectors/kafka/KafkaSerializationSchema.java