curcur commented on a change in pull request #11725: URL: https://github.com/apache/flink/pull/11725#discussion_r425570222
########## File path: flink-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/shuffle/FlinkKafkaShuffle.java ########## @@ -0,0 +1,231 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.flink.streaming.connectors.kafka.shuffle; + +import org.apache.flink.annotation.Experimental; +import org.apache.flink.api.common.operators.Keys; +import org.apache.flink.api.common.serialization.TypeInformationSerializationSchema; +import org.apache.flink.api.common.typeinfo.BasicArrayTypeInfo; +import org.apache.flink.api.common.typeinfo.PrimitiveArrayTypeInfo; +import org.apache.flink.api.java.functions.KeySelector; +import org.apache.flink.api.java.tuple.Tuple; +import org.apache.flink.streaming.api.datastream.DataStream; +import org.apache.flink.streaming.api.datastream.DataStreamUtils; +import org.apache.flink.streaming.api.datastream.KeyedStream; +import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment; +import org.apache.flink.streaming.api.functions.source.SourceFunction; +import org.apache.flink.streaming.api.transformations.SinkTransformation; +import org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer; +import org.apache.flink.streaming.util.keys.KeySelectorUtil; +import org.apache.flink.util.Preconditions; +import org.apache.flink.util.PropertiesUtil; + +import java.util.Properties; + +/** + * Use Kafka as a persistent shuffle by wrapping a Kafka Source/Sink pair together. + */ +@Experimental +class FlinkKafkaShuffle { + static final String PRODUCER_PARALLELISM = "producer parallelism"; + static final String PARTITION_NUMBER = "partition number"; + + /** + * Write to and read from a kafka shuffle with the partition decided by keys. + * Consumers should read partitions equal to the key group indices they are assigned. + * The number of partitions is the maximum parallelism of the receiving operator. + * This version only supports numberOfPartitions = consumerParallelism. Review comment: Do you mean specifically saying "producerParallelism != numberOfPartitions?" If think this is keyBy through a persistent channel, the producer parallelism does not matter with the max key group size? I kind of feeling confusing if adding such a comment. For config changes, yes, probably in the next step; Overall, this is only a very first version, allowing users to set parallelism when writing pipelines might be enough. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org