cmccabe commented on code in PR #14628: URL: https://github.com/apache/kafka/pull/14628#discussion_r1373533083
########## metadata/src/main/java/org/apache/kafka/metadata/properties/PropertiesUtils.java: ########## @@ -0,0 +1,102 @@ +/* + * 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.metadata.properties; + +import org.apache.kafka.common.utils.Utils; + +import java.io.File; +import java.io.FileOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStreamWriter; +import java.io.PrintWriter; +import java.nio.charset.StandardCharsets; +import java.nio.file.Files; +import java.nio.file.Paths; +import java.util.Properties; + +public final class PropertiesUtils { + /** + * Writes a Java Properties object to a file. + * + * @param props The Properties object. + * @param path The file to write to. + * @throws IOException + */ + public static void writePropertiesFile( + Properties props, + String path + ) throws IOException { + File tempFile = new File(path + ".tmp"); + try ( + FileOutputStream fos = new FileOutputStream(tempFile, false); + OutputStreamWriter osw = new OutputStreamWriter(fos, StandardCharsets.UTF_8); + PrintWriter pw = new PrintWriter(osw) + ) { + props.store(pw, ""); + fos.flush(); + fos.getFD().sync(); Review Comment: This is what the previous code in `BrokerMetadataCheckpoint.scala` did. The reason for doing it this way is for extra safety, as @pprovenzano commented. Some filesystems (I think ext3 was a notable offender) tended to lose data when fsync was omitted, even in the case where other operations like rename were performed later. Since we only very rarely write the `meta.properties` file, it's surely not worth optimizing this by avoiding the fsync. -- 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
