CalvinConfluent commented on code in PR #14465: URL: https://github.com/apache/kafka/pull/14465#discussion_r1361372153
########## core/src/main/java/kafka/log/CleanShutdownFileHandler.java: ########## @@ -0,0 +1,132 @@ +/* + * 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 kafka.log; + +import com.fasterxml.jackson.databind.ObjectMapper; +import org.apache.kafka.common.utils.LogContext; +import org.slf4j.Logger; + +import java.io.BufferedReader; +import java.io.File; +import java.io.FileOutputStream; +import java.io.BufferedWriter; +import java.io.IOException; +import java.io.OutputStreamWriter; +import java.nio.charset.StandardCharsets; +import java.nio.file.Files; +import java.util.HashMap; +import java.util.Locale; +import java.util.Map; +import java.util.stream.Collectors; + +/** + * Clean shutdown file that indicates the broker was cleanly shutdown in 0.8 and higher. + * This is used to avoid unnecessary recovery after a clean shutdown. In theory this could be + * avoided by passing in the recovery point, however finding the correct position to do this + * requires accessing the offset index which may not be safe in an unclean shutdown. + * For more information see the discussion in PR#2104 + * + * Also, the clean shutdown file can also store the broker epoch, this can be used in the broker registration to + * demonstrate the last reboot is a clean shutdown. (KIP-966) + */ + +public class CleanShutdownFileHandler { + public static final String CLEAN_SHUTDOWN_FILE_NAME = ".kafka_cleanshutdown"; + File cleanShutdownFile; + int currentVersion = 0; + private final Logger logger; + + private enum Fields { + VERSION, + BROKER_EPOCH; + + @Override + public String toString() { + return name().toLowerCase(Locale.ROOT); + } + } + + public CleanShutdownFileHandler(String dirPath) { + logger = new LogContext().logger(CleanShutdownFileHandler.class); + try { + this.cleanShutdownFile = new File(dirPath, CleanShutdownFileHandler.CLEAN_SHUTDOWN_FILE_NAME); + } catch (Exception e) { + logger.warn("Fail to initiate the clean shutdown file handler: " + e); + } + } + + public void write(long brokerEpoch) throws Exception { Review Comment: Made them all public. ########## metadata/src/main/java/org/apache/kafka/controller/ClusterControlManager.java: ########## @@ -327,6 +328,9 @@ public ControllerResult<BrokerRegistrationReply> registerBroker( } int brokerId = request.brokerId(); BrokerRegistration existing = brokerRegistrations.get(brokerId); + if (version < 2 || request.previousBrokerEpoch() != existing.epoch()) { + log.debug("Received an unclean shutdown request"); Review Comment: Done -- 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
