satishd commented on a change in pull request #11390: URL: https://github.com/apache/kafka/pull/11390#discussion_r796479255
########## File path: clients/src/main/java/org/apache/kafka/common/record/RemoteLogInputStream.java ########## @@ -0,0 +1,75 @@ +/* + * 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.common.record; + +import org.apache.kafka.common.errors.CorruptRecordException; +import org.apache.kafka.common.utils.Utils; + +import java.io.IOException; +import java.io.InputStream; +import java.nio.ByteBuffer; + +import static org.apache.kafka.common.record.Records.HEADER_SIZE_UP_TO_MAGIC; +import static org.apache.kafka.common.record.Records.LOG_OVERHEAD; +import static org.apache.kafka.common.record.Records.MAGIC_OFFSET; +import static org.apache.kafka.common.record.Records.OFFSET_OFFSET; +import static org.apache.kafka.common.record.Records.SIZE_OFFSET; + +public class RemoteLogInputStream implements LogInputStream<RecordBatch> { + private final InputStream is; + private final ByteBuffer logHeaderBuffer = ByteBuffer.allocate(HEADER_SIZE_UP_TO_MAGIC); + + public RemoteLogInputStream(InputStream is) { + this.is = is; + } + + @Override + public RecordBatch nextBatch() throws IOException { + logHeaderBuffer.rewind(); + Utils.readFully(is, logHeaderBuffer); + + if (logHeaderBuffer.position() < HEADER_SIZE_UP_TO_MAGIC) + return null; + + logHeaderBuffer.rewind(); + logHeaderBuffer.getLong(OFFSET_OFFSET); + int size = logHeaderBuffer.getInt(SIZE_OFFSET); + + // V0 has the smallest overhead, stricter checking is done later + if (size < LegacyRecord.RECORD_OVERHEAD_V0) + throw new CorruptRecordException(String.format("Found record size %d smaller than minimum record " + + "overhead (%d).", size, LegacyRecord.RECORD_OVERHEAD_V0)); + + byte magic = logHeaderBuffer.get(MAGIC_OFFSET); + ByteBuffer buffer = ByteBuffer.allocate(size + LOG_OVERHEAD); + buffer.put(logHeaderBuffer); + buffer.position(logHeaderBuffer.limit()); + + Utils.readFully(is, buffer); Review comment: No, we do not really need more space here. I updated with more comments in the code on how it works. This is aligned with the existing code in other places like `FileChannelRecordBatch`. payload : LOG_OVERHEAD + 4 + 1 (magic:byte) + reocrd-content LOG_OVERHEAD = 8(offset:long) + 4(size:int) = 12 `size` = 4 + 1(magic) + record-content-size. `logHeaderBuffer` is read until magic. That is why the complete buffer-size is 12(LOG_OVERHEAD) + size. We do not count "4 + 1(magic)" here as it is already taken into account with size_read_from_header -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
