mjsax commented on code in PR #21666: URL: https://github.com/apache/kafka/pull/21666#discussion_r2902505905
########## streams/src/main/java/org/apache/kafka/streams/state/internals/PlainToHeadersStoreAdapter.java: ########## @@ -0,0 +1,239 @@ +/* + * 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.TopicPartition; +import org.apache.kafka.common.serialization.Serializer; +import org.apache.kafka.common.utils.ByteUtils; +import org.apache.kafka.common.utils.Bytes; +import org.apache.kafka.streams.KeyValue; +import org.apache.kafka.streams.kstream.Materialized; +import org.apache.kafka.streams.processor.StateStore; +import org.apache.kafka.streams.processor.StateStoreContext; +import org.apache.kafka.streams.query.KeyQuery; +import org.apache.kafka.streams.query.Position; +import org.apache.kafka.streams.query.PositionBound; +import org.apache.kafka.streams.query.Query; +import org.apache.kafka.streams.query.QueryConfig; +import org.apache.kafka.streams.query.QueryResult; +import org.apache.kafka.streams.query.RangeQuery; +import org.apache.kafka.streams.query.internals.InternalQueryResultUtil; +import org.apache.kafka.streams.state.KeyValueBytesStoreSupplier; +import org.apache.kafka.streams.state.KeyValueIterator; +import org.apache.kafka.streams.state.KeyValueStore; +import org.apache.kafka.streams.state.TimestampedBytesStore; +import org.apache.kafka.streams.state.TimestampedKeyValueStoreWithHeaders; + +import java.nio.ByteBuffer; +import java.util.List; +import java.util.Map; + +import static org.apache.kafka.streams.state.HeadersBytesStore.convertFromPlainToHeaderFormat; + +/** + * This class is used to ensure backward compatibility at DSL level between + * {@link TimestampedKeyValueStoreWithHeaders} and plain {@link KeyValueStore}. + * <p> + * If a user provides a supplier for plain {@code KeyValueStore} (without timestamp or headers) via + * {@link Materialized#as(KeyValueBytesStoreSupplier)} when building + * a {@code TimestampedKeyValueStoreWithHeaders}, this adapter is used to translate between + * the plain {@code byte[]} format and the timestamped-with-headers {@code byte[]} format. + * + * @see PlainToHeadersIteratorAdapter + */ +@SuppressWarnings("unchecked") +public class PlainToHeadersStoreAdapter implements KeyValueStore<Bytes, byte[]> { + final KeyValueStore<Bytes, byte[]> store; + + PlainToHeadersStoreAdapter(final KeyValueStore<Bytes, byte[]> store) { + if (!store.persistent()) { + throw new IllegalArgumentException("Provided store must be a persistent store, but it is not."); + } + if (store instanceof TimestampedBytesStore) { + throw new IllegalArgumentException("Provided store must be a plain (non-timestamped) key value store, but it is timestamped."); + } + this.store = store; + } + + /** + * Extract raw plain value from serialized ValueTimestampHeaders. + * This strips both the headers and timestamp portions. + * + * Format conversion: + * Input: [headersSize(varint)][headers][timestamp(8)][value] + * Output: [value] + */ + static byte[] rawPlainValue(final byte[] rawValueTimestampHeaders) { Review Comment: Should we follow https://github.com/apache/kafka/pull/21626 and add `UtilsTest` class in this PR -- to avoid piling up more stuff we need to refactor? -- 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]
