smjn commented on code in PR #16921: URL: https://github.com/apache/kafka/pull/16921#discussion_r1730849021
########## coordinator-common/src/main/java/org/apache/kafka/coordinator/common/runtime/CoordinatorRecordSerde.java: ########## @@ -0,0 +1,122 @@ +/* + * 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.kafka.coordinator.common.runtime; + +import org.apache.kafka.common.protocol.ApiMessage; +import org.apache.kafka.common.protocol.ByteBufferAccessor; +import org.apache.kafka.common.protocol.MessageUtil; +import org.apache.kafka.server.common.ApiMessageAndVersion; + +import java.nio.BufferUnderflowException; +import java.nio.ByteBuffer; + +/** + * Serializer/Deserializer for {@link CoordinatorRecord}. The format is defined below: + * <pre> + * record_key = [record_type key_message] + * record_value = [value_version value_message] + * + * record_type : The record type is currently define as the version of the key + * {@link ApiMessageAndVersion} object. + * key_message : The serialized message of the key {@link ApiMessageAndVersion} object. + * value_version : The value version is currently define as the version of the value + * {@link ApiMessageAndVersion} object. + * value_message : The serialized message of the value {@link ApiMessageAndVersion} object. + * </pre> + */ +public abstract class CoordinatorRecordSerde implements Serializer<CoordinatorRecord>, Deserializer<CoordinatorRecord> { + @Override + public byte[] serializeKey(CoordinatorRecord record) { + // Record does not accept a null key. + return MessageUtil.toVersionPrefixedBytes( + record.key().version(), + record.key().message() + ); + } + + @Override + public byte[] serializeValue(CoordinatorRecord record) { + // Tombstone is represented with a null value. + if (record.value() == null) { + return null; + } else { + return MessageUtil.toVersionPrefixedBytes( + record.value().version(), + record.value().message() + ); + } + } + + @Override + public CoordinatorRecord deserialize( + ByteBuffer keyBuffer, + ByteBuffer valueBuffer + ) throws RuntimeException { + final short recordType = readVersion(keyBuffer, "key"); + final ApiMessage keyMessage = apiMessageKeyFor(recordType); + readMessage(keyMessage, keyBuffer, recordType, "key"); + + if (valueBuffer == null) { + return new CoordinatorRecord(new ApiMessageAndVersion(keyMessage, recordType), null); + } + + final ApiMessage valueMessage = apiMessageValueFor(recordType); + final short valueVersion = readVersion(valueBuffer, "value"); + readMessage(valueMessage, valueBuffer, valueVersion, "value"); + + return new CoordinatorRecord( + new ApiMessageAndVersion(keyMessage, recordType), + new ApiMessageAndVersion(valueMessage, valueVersion) + ); + } + + private short readVersion(ByteBuffer buffer, String name) throws RuntimeException { + try { + return buffer.getShort(); + } catch (BufferUnderflowException ex) { + throw new RuntimeException(String.format("Could not read version from %s's buffer.", name)); + } + } + + private void readMessage(ApiMessage message, ByteBuffer buffer, short version, String name) throws RuntimeException { + try { + message.read(new ByteBufferAccessor(buffer), version); Review Comment: The version checks are for the data fields and the "validVersions" record field. Additionally, there are 2 methods hightestSupportedVersion and lowestSupportedVersion which specify the range If the version is such that it is not handled by `apiMessageKeyFor` or `apiMessageValueFor`, it will throw the exception. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
