gaborgsomogyi commented on code in PR #364: URL: https://github.com/apache/flink-kubernetes-operator/pull/364#discussion_r964963833
########## flink-kubernetes-operator/src/main/java/org/apache/flink/kubernetes/operator/fs/FileSystemWatchService.java: ########## @@ -0,0 +1,94 @@ +/* + * 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.flink.kubernetes.operator.fs; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.io.File; +import java.nio.file.FileSystems; +import java.nio.file.Path; +import java.nio.file.Paths; +import java.nio.file.WatchEvent; +import java.nio.file.WatchKey; +import java.nio.file.WatchService; + +import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE; +import static java.nio.file.StandardWatchEventKinds.ENTRY_DELETE; +import static java.nio.file.StandardWatchEventKinds.ENTRY_MODIFY; +import static java.nio.file.StandardWatchEventKinds.OVERFLOW; + +/** Service which is able to watch local filesystem directories. */ +public class FileSystemWatchService extends Thread { + private static final Logger LOG = LoggerFactory.getLogger(FileSystemWatchService.class); + + private final String directoryPath; + + public FileSystemWatchService(String directoryPath) { + if (!new File(directoryPath).isDirectory()) { + throw new IllegalArgumentException("Directory must exists: " + directoryPath); + } + this.directoryPath = directoryPath; + } + + @Override + public void run() { + try (WatchService watcher = FileSystems.getDefault().newWatchService()) { + LOG.info("Starting watching path: " + directoryPath); + Path realDirectoryPath = Paths.get(directoryPath).toRealPath(); + LOG.info("Path is resolved to real path: " + realDirectoryPath); + realDirectoryPath.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY); + onWatchStarted(realDirectoryPath); + + while (true) { + LOG.debug("Taking watch key"); + WatchKey watchKey = watcher.take(); + LOG.debug("Watch key arrived"); + for (WatchEvent<?> watchEvent : watchKey.pollEvents()) { + LOG.debug("Watch event count: " + watchEvent.count()); + if (watchEvent.kind() == OVERFLOW) { + LOG.error("Filesystem events may have been lost or discarded"); + Thread.yield(); + } else if (watchEvent.kind() == ENTRY_CREATE) { + onFileOrDirectoryCreated((Path) watchEvent.context()); + } else if (watchEvent.kind() == ENTRY_DELETE) { + onFileOrDirectoryDeleted((Path) watchEvent.context()); + } else if (watchEvent.kind() == ENTRY_MODIFY) { + onFileOrDirectoryModified((Path) watchEvent.context()); + } else { + throw new IllegalStateException("Invalid event kind: " + watchEvent.kind()); + } + } + watchKey.reset(); + } + } catch (InterruptedException e) { + LOG.info("Filesystem watcher interrupted"); Review Comment: If something is happening silently that is a so called `silent killer` in my understanding. One just stares to a 1k nodes cluster which is not working and has no idea from the logs what has happened. -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
