001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.camel.component.file.strategy;
018
019 import java.io.File;
020
021 import org.apache.camel.Exchange;
022 import org.apache.camel.LoggingLevel;
023 import org.apache.camel.component.file.FileComponent;
024 import org.apache.camel.component.file.GenericFile;
025 import org.apache.camel.component.file.GenericFileEndpoint;
026 import org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy;
027 import org.apache.camel.component.file.GenericFileOperations;
028 import org.apache.camel.util.FileUtil;
029 import org.apache.camel.util.StopWatch;
030 import org.slf4j.Logger;
031 import org.slf4j.LoggerFactory;
032
033 /**
034 * Acquires read lock to the given file using a marker file so other Camel consumers wont acquire the same file.
035 * This is the default behavior in Camel 1.x.
036 */
037 public class MarkerFileExclusiveReadLockStrategy implements GenericFileExclusiveReadLockStrategy<File> {
038 private static final Logger LOG = LoggerFactory.getLogger(MarkerFileExclusiveReadLockStrategy.class);
039
040 @Override
041 public void prepareOnStartup(GenericFileOperations<File> operations, GenericFileEndpoint<File> endpoint) {
042 String dir = endpoint.getConfiguration().getDirectory();
043 File file = new File(dir);
044
045 LOG.debug("Prepare on startup by deleting orphaned lock files from: {}", dir);
046
047 StopWatch watch = new StopWatch();
048 deleteLockFiles(file, endpoint.isRecursive());
049
050 // log anything that takes more than a second
051 if (watch.taken() > 1000) {
052 LOG.info("Prepared on startup by deleting orphaned lock files from: {} took {} millis to complete.", dir, watch.taken());
053 }
054 }
055
056 @Override
057 public boolean acquireExclusiveReadLock(GenericFileOperations<File> operations,
058 GenericFile<File> file, Exchange exchange) throws Exception {
059 String lockFileName = getLockFileName(file);
060 LOG.trace("Locking the file: {} using the lock file name: {}", file, lockFileName);
061
062 // create a plain file as marker filer for locking (do not use FileLock)
063 boolean acquired = FileUtil.createNewFile(new File(lockFileName));
064 exchange.setProperty(Exchange.FILE_LOCK_FILE_ACQUIRED, acquired);
065 exchange.setProperty(Exchange.FILE_LOCK_FILE_NAME, lockFileName);
066
067 return acquired;
068 }
069
070 @Override
071 public void releaseExclusiveReadLock(GenericFileOperations<File> operations,
072 GenericFile<File> file, Exchange exchange) throws Exception {
073 String lockFileName = exchange.getProperty(Exchange.FILE_LOCK_FILE_NAME, getLockFileName(file), String.class);
074 File lock = new File(lockFileName);
075 // only release the file if camel get the lock before
076 if (exchange.getProperty(Exchange.FILE_LOCK_FILE_ACQUIRED, false, Boolean.class)) {
077 LOG.trace("Unlocking file: {}", lockFileName);
078 boolean deleted = FileUtil.deleteFile(lock);
079 LOG.trace("Lock file: {} was deleted: {}", lockFileName, deleted);
080 } else {
081 LOG.trace("Don't try to delete the Lock file: {} as camel doesn't get to lock before.", lockFileName);
082 }
083 }
084
085 @Override
086 public void setTimeout(long timeout) {
087 // noop
088 }
089
090 @Override
091 public void setCheckInterval(long checkInterval) {
092 // noop
093 }
094
095 @Override
096 public void setReadLockLoggingLevel(LoggingLevel readLockLoggingLevel) {
097 // noop
098 }
099
100 private static void deleteLockFiles(File dir, boolean recursive) {
101 File[] files = dir.listFiles();
102 if (files == null || files.length == 0) {
103 return;
104 }
105
106 for (File file : files) {
107 if (file.getName().startsWith(".")) {
108 // files starting with dot should be skipped
109 continue;
110 } else if (file.getName().endsWith(FileComponent.DEFAULT_LOCK_FILE_POSTFIX)) {
111 LOG.warn("Deleting orphaned lock file: " + file);
112 FileUtil.deleteFile(file);
113 } else if (recursive && file.isDirectory()) {
114 deleteLockFiles(file, true);
115 }
116 }
117 }
118
119 private static String getLockFileName(GenericFile<File> file) {
120 return file.getAbsoluteFilePath() + FileComponent.DEFAULT_LOCK_FILE_POSTFIX;
121 }
122
123 }