mjsax commented on code in PR #21455: URL: https://github.com/apache/kafka/pull/21455#discussion_r2834784534
########## streams/src/main/java/org/apache/kafka/streams/state/internals/TimestampedToHeadersStoreAdapter.java: ########## @@ -0,0 +1,301 @@ +/* + * 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.TimestampedKeyQuery; +import org.apache.kafka.streams.query.TimestampedRangeQuery; +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.TimestampedKeyValueStore; +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.convertToHeaderFormat; + +/** + * This class is used to ensure backward compatibility at DSL level between + * {@link TimestampedKeyValueStoreWithHeaders} and + * {@link TimestampedKeyValueStore}. + * <p> + * If a user provides a supplier for {@code TimestampedKeyValueStore} (without headers) via + * {@link Materialized#as(KeyValueBytesStoreSupplier)} when building + * a {@code TimestampedKeyValueStoreWithHeaders}, this adapter is used to translate between + * the timestamped {@code byte[]} format and the timestamped-with-headers {@code byte[]} format. + * + * @see TimestampedToHeadersIteratorAdapter + */ +@SuppressWarnings("unchecked") +public class TimestampedToHeadersStoreAdapter implements KeyValueStore<Bytes, byte[]> { + final KeyValueStore<Bytes, byte[]> store; + + TimestampedToHeadersStoreAdapter(final KeyValueStore<Bytes, byte[]> store) { + if (!store.persistent()) { + throw new IllegalArgumentException("Provided store must be a persistent store, but it is not."); + } + this.store = store; + } + + /** + * Extract raw timestamped value (timestamp + value) from serialized ValueTimestampHeaders. + * This strips the headers portion but keeps timestamp and value intact. + * + * Format conversion: + * Input: [headersSize(varint)][headers][timestamp(8)][value] + * Output: [timestamp(8)][value] + */ + static byte[] rawTimestampedValue(final byte[] rawValueTimestampHeaders) { + if (rawValueTimestampHeaders == null) { + return null; + } + + final ByteBuffer buffer = ByteBuffer.wrap(rawValueTimestampHeaders); + final int headersSize = ByteUtils.readVarint(buffer); + // Skip headers, keep timestamp + value + buffer.position(buffer.position() + headersSize); + + final byte[] result = new byte[buffer.remaining()]; + buffer.get(result); + return result; + } + + @Override + public void put(final Bytes key, + final byte[] valueWithTimestampAndHeaders) { + store.put(key, rawTimestampedValue(valueWithTimestampAndHeaders)); + } + + @Override + public byte[] putIfAbsent(final Bytes key, + final byte[] valueWithTimestampAndHeaders) { + return convertToHeaderFormat(store.putIfAbsent( + key, + rawTimestampedValue(valueWithTimestampAndHeaders))); + } + + @Override + public void putAll(final List<KeyValue<Bytes, byte[]>> entries) { + for (final KeyValue<Bytes, byte[]> entry : entries) { + final byte[] valueWithTimestampAndHeaders = entry.value; + store.put(entry.key, rawTimestampedValue(valueWithTimestampAndHeaders)); + } + } + + @Override + public byte[] delete(final Bytes key) { + return convertToHeaderFormat(store.delete(key)); + } + + @Override + public String name() { + return store.name(); + } + + @Override + public void init(final StateStoreContext stateStoreContext, final StateStore root) { + store.init(stateStoreContext, root); + } + + @Override + public void commit(final Map<TopicPartition, Long> changelogOffsets) { + store.commit(changelogOffsets); + } + + @Override + public void close() { + store.close(); + } + + @Override + public boolean persistent() { + return true; + } + + @Override + public boolean isOpen() { + return store.isOpen(); + } + + @Override + public <R> QueryResult<R> query( + final Query<R> query, + final PositionBound positionBound, + final QueryConfig config) { + + final long start = config.isCollectExecutionInfo() ? System.nanoTime() : -1L; + QueryResult<R> result = store.query(query, positionBound, config); + + // this adapter always needs to return a `value-with-timestamp-and-headers` result to hold up its contract + // thus, we need to add the empty headers wrapper even for timestamped queries + if (result.isSuccess()) { + if (query instanceof KeyQuery || query instanceof TimestampedKeyQuery) { + final byte[] timestampedValue = (byte[]) result.getResult(); + final byte[] valueWithHeaders = convertToHeaderFormat(timestampedValue); + result = (QueryResult<R>) InternalQueryResultUtil.copyAndSubstituteDeserializedResult(result, valueWithHeaders); + } else if (query instanceof RangeQuery || query instanceof TimestampedRangeQuery) { + final TimestampedToHeadersRocksIteratorAdapter wrappedRocksDBRangeIterator = + new TimestampedToHeadersRocksIteratorAdapter((RocksDbIterator) result.getResult()); + result = (QueryResult<R>) InternalQueryResultUtil.copyAndSubstituteDeserializedResult(result, wrappedRocksDBRangeIterator); + } else { + throw new IllegalArgumentException("Unsupported query type: " + query.getClass()); + } + } + + if (config.isCollectExecutionInfo()) { + final long end = System.nanoTime(); + result.addExecutionInfo( + "Handled in " + getClass() + " in " + (end - start) + "ns" + ); + } + return result; + } + + @Override + public Position getPosition() { + return store.getPosition(); + } + + @Override + public byte[] get(final Bytes key) { + return convertToHeaderFormat(store.get(key)); + } + + @Override + public KeyValueIterator<Bytes, byte[]> range(final Bytes from, + final Bytes to) { + return new TimestampedToHeadersIteratorAdapter<>(store.range(from, to)); + } + + @Override + public KeyValueIterator<Bytes, byte[]> reverseRange(final Bytes from, + final Bytes to) { + return new TimestampedToHeadersIteratorAdapter<>(store.reverseRange(from, to)); + } + + @Override + public KeyValueIterator<Bytes, byte[]> all() { + return new TimestampedToHeadersIteratorAdapter<>(store.all()); + } + + @Override + public KeyValueIterator<Bytes, byte[]> reverseAll() { + return new TimestampedToHeadersIteratorAdapter<>(store.reverseAll()); + } + + @Override + public <PS extends Serializer<P>, P> KeyValueIterator<Bytes, byte[]> prefixScan(final P prefix, + final PS prefixKeySerializer) { + return new TimestampedToHeadersIteratorAdapter<>(store.prefixScan(prefix, prefixKeySerializer)); + } + + @Override + public long approximateNumEntries() { + return store.approximateNumEntries(); + } + + /** + * Generic iterator adapter for range/all operations + */ + private static class TimestampedToHeadersIteratorAdapter<K> implements KeyValueIterator<K, byte[]> { Review Comment: There is two classes with very similar names... `KeyValueToTimestampedKeyValueIteratorAdapter` (is a standalone class), and there is also `KeyValueToTimestampedKeyValueAdapterIterator` which is the private one... (we would rename the private one as a pointed out on some other comment to get better names -- very easy to mix up) -- 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]
