/**
* 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.camel.component.file.strategy;
import java.io.File;
import org.apache.camel.Exchange;
import org.apache.camel.LoggingLevel;
import org.apache.camel.component.file.FileComponent;
import org.apache.camel.component.file.GenericFile;
import org.apache.camel.component.file.GenericFileEndpoint;
import org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy;
import org.apache.camel.component.file.GenericFileOperations;
import org.apache.camel.util.FileUtil;
import org.apache.camel.util.StopWatch;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Acquires read lock to the given file using a marker file so other Camel consumers wont acquire the same file.
* This is the default behavior in Camel 1.x.
*/
public class MarkerFileExclusiveReadLockStrategy implements GenericFileExclusiveReadLockStrategy<File> {
private static final Logger LOG = LoggerFactory.getLogger(MarkerFileExclusiveReadLockStrategy.class);
@Override
public void prepareOnStartup(GenericFileOperations<File> operations, GenericFileEndpoint<File> endpoint) {
String dir = endpoint.getConfiguration().getDirectory();
File file = new File(dir);
LOG.debug("Prepare on startup by deleting orphaned lock files from: {}", dir);
StopWatch watch = new StopWatch();
deleteLockFiles(file, endpoint.isRecursive());
// log anything that takes more than a second
if (watch.taken() > 1000) {
LOG.info("Prepared on startup by deleting orphaned lock files from: {} took {} millis to complete.", dir, watch.taken());
}
}
@Override
public boolean acquireExclusiveReadLock(GenericFileOperations<File> operations,
GenericFile<File> file, Exchange exchange) throws Exception {
String lockFileName = getLockFileName(file);
LOG.trace("Locking the file: {} using the lock file name: {}", file, lockFileName);
// create a plain file as marker filer for locking (do not use FileLock)
boolean acquired = FileUtil.createNewFile(new File(lockFileName));
exchange.setProperty(Exchange.FILE_LOCK_FILE_ACQUIRED, acquired);
exchange.setProperty(Exchange.FILE_LOCK_FILE_NAME, lockFileName);
return acquired;
}
@Override
public void releaseExclusiveReadLock(GenericFileOperations<File> operations,
GenericFile<File> file, Exchange exchange) throws Exception {
String lockFileName = exchange.getProperty(Exchange.FILE_LOCK_FILE_NAME, getLockFileName(file), String.class);
File lock = new File(lockFileName);
// only release the file if camel get the lock before
if (exchange.getProperty(Exchange.FILE_LOCK_FILE_ACQUIRED, false, Boolean.class)) {
LOG.trace("Unlocking file: {}", lockFileName);
boolean deleted = FileUtil.deleteFile(lock);
LOG.trace("Lock file: {} was deleted: {}", lockFileName, deleted);
} else {
LOG.trace("Don't try to delete the Lock file: {} as camel doesn't get to lock before.", lockFileName);
}
}
@Override
public void setTimeout(long timeout) {
// noop
}
@Override
public void setCheckInterval(long checkInterval) {
// noop
}
@Override
public void setReadLockLoggingLevel(LoggingLevel readLockLoggingLevel) {
// noop
}
private static void deleteLockFiles(File dir, boolean recursive) {
File[] files = dir.listFiles();
if (files == null || files.length == 0) {
return;
}
for (File file : files) {
if (file.getName().startsWith(".")) {
// files starting with dot should be skipped
continue;
} else if (file.getName().endsWith(FileComponent.DEFAULT_LOCK_FILE_POSTFIX)) {
LOG.warn("Deleting orphaned lock file: " + file);
FileUtil.deleteFile(file);
} else if (recursive && file.isDirectory()) {
deleteLockFiles(file, true);
}
}
}
private static String getLockFileName(GenericFile<File> file) {
return file.getAbsoluteFilePath() + FileComponent.DEFAULT_LOCK_FILE_POSTFIX;
}
}