UladzislauBlok commented on code in PR #21401: URL: https://github.com/apache/kafka/pull/21401#discussion_r2782409369
########## streams/src/main/java/org/apache/kafka/streams/state/internals/HeadersSerializer.java: ########## @@ -0,0 +1,88 @@ +/* + * 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.streams.state.internals; + +import org.apache.kafka.common.header.Header; +import org.apache.kafka.common.header.Headers; +import org.apache.kafka.common.serialization.Serializer; +import org.apache.kafka.common.utils.ByteUtils; + +import java.io.ByteArrayOutputStream; +import java.io.DataOutputStream; +import java.io.IOException; +import java.nio.charset.StandardCharsets; + +/** + * Serializer for Kafka Headers. + * <p> + * Serialization format (per KIP-1271): + * [NumHeaders(varint)][Header1][Header2]... + * <p> + * Each header: + * [KeyLength(varint)][KeyBytes(UTF-8)][ValueLength(varint)][ValueBytes] + * <p> + * Note: ValueLength is -1 for null values (encoded as varint). + * All integers are encoded as varints (signed varint encoding). + * <p> + * This serializer produces the headersBytes portion. The headersSize prefix + * is added by the outer serializer (e.g., ValueTimestampHeadersSerializer). + * <p> + * This is used by KIP-1271 to serialize headers for storage in state stores. + */ +public class HeadersSerializer implements Serializer<Headers> { Review Comment: I have a question regarding API. I checked many serializers, but I wasn't able to find any uses of `String topic` parameter. Why do we need this at all? Is it for custom serializers? -- 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]
