cmccabe commented on code in PR #12776: URL: https://github.com/apache/kafka/pull/12776#discussion_r1011299603
########## metadata/src/main/java/org/apache/kafka/image/publisher/SnapshotEmitter.java: ########## @@ -0,0 +1,118 @@ +/* + * 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.image.publisher; + + +import org.apache.kafka.common.utils.LogContext; +import org.apache.kafka.image.MetadataImage; +import org.apache.kafka.image.MetadataProvenance; +import org.apache.kafka.image.writer.ImageWriterOptions; +import org.apache.kafka.image.writer.RaftSnapshotWriter; +import org.apache.kafka.raft.RaftClient; +import org.apache.kafka.server.common.ApiMessageAndVersion; +import org.apache.kafka.snapshot.SnapshotWriter; +import org.slf4j.Logger; + +import java.util.Optional; + +public class SnapshotEmitter implements SnapshotGenerator.Emitter { + private final static int DEFAULT_BATCH_SIZE = 100; + + public static class Builder { + private int nodeId = 0; + private RaftClient<ApiMessageAndVersion> raftClient = null; + private int batchSize = DEFAULT_BATCH_SIZE; + + public Builder setNodeId(int nodeId) { + this.nodeId = nodeId; + return this; + } + + public Builder setRaftClient(RaftClient<ApiMessageAndVersion> raftClient) { + this.raftClient = raftClient; + return this; + } + + public Builder setBatchSize(int batchSize) { + this.batchSize = batchSize; + return this; + } + + public SnapshotEmitter build() { + if (raftClient == null) throw new RuntimeException("You must set the raftClient."); + return new SnapshotEmitter(nodeId, + raftClient, + batchSize); + } + } + + /** + * The slf4j logger to use. + */ + private final Logger log; + + /** + * The RaftClient to use. + */ + private final RaftClient<ApiMessageAndVersion> raftClient; + + /** + * The maximum number of records to put in each batch. + */ + private final int batchSize; + + private SnapshotEmitter( + int nodeId, + RaftClient<ApiMessageAndVersion> raftClient, + int batchSize + ) { + this.log = new LogContext("[SnapshotEmitter id=" + nodeId + "] ").logger(SnapshotEmitter.class); + this.raftClient = raftClient; + this.batchSize = batchSize; + } + + @Override + public void emit(MetadataImage image) { + MetadataProvenance provenance = image.provenance(); + Optional<SnapshotWriter<ApiMessageAndVersion>> snapshotWriter = + raftClient.createSnapshot(provenance.offset(), + provenance.epoch(), + provenance.lastContainedLogTimeMs()); + if (!snapshotWriter.isPresent()) { + log.error("Not generating {} because it already exists.", provenance.snapshotName()); + return; + } + try (RaftSnapshotWriter writer = new RaftSnapshotWriter(snapshotWriter.get(), batchSize)) { + image.write(writer, new ImageWriterOptions.Builder(). + setMetadataVersion(image.features().metadataVersion()). + build()); + writer.close(true); + } catch (Throwable e) { + log.error("Encountered error while writing {}", provenance.snapshotName(), e); + throw e; + } finally { + try { + snapshotWriter.get().close(); Review Comment: Yeah, that's a fair point. I'm sure that this ordering is defined by Java, but it's a bit esoteric. I was assuming that the close order didn't matter, but perhaps it does (or will eventually?) Best just to be straightforward about it. Since they're both AutoCloseable, I will also use `Utils.closeQuietly` as well. -- 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
