/*
* (C) Copyright 2006-2014 Nuxeo SA (http://nuxeo.com/) and others.
*
* Licensed 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.nuxeo.runtime.trackers.files;
import java.io.File;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArrayList;
import org.apache.commons.io.FileCleaningTracker;
import org.apache.commons.io.FileDeleteStrategy;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.nuxeo.common.xmap.annotation.XObject;
import org.nuxeo.runtime.api.Framework;
import org.nuxeo.runtime.model.ComponentContext;
import org.nuxeo.runtime.model.ComponentInstance;
import org.nuxeo.runtime.model.DefaultComponent;
import org.nuxeo.runtime.services.event.EventService;
import org.nuxeo.runtime.trackers.concurrent.ThreadEventHandler;
import org.nuxeo.runtime.trackers.concurrent.ThreadEventListener;
/**
* Files event tracker which delete files once the runtime leave the threads or at least once the associated marker
* object is garbaged. Note: for being backward compatible you may disable the thread events tracking by black-listing
* the default configuration component "org.nuxeo.runtime.trackers.files.threadstracking.config" in the runtime. This
* could be achieved by editing the "blacklist" file in your 'config' directory or using the @{link BlacklistComponent}
* annotation on your test class.
*
* @author Stephane Lacoin at Nuxeo (aka matic)
* @since 6.0
* @see ThreadEventHandler
*/
public class FileEventTracker extends DefaultComponent {
protected static final Log log = LogFactory.getLog(FileEventTracker.class);
protected static SafeFileDeleteStrategy deleteStrategy = new SafeFileDeleteStrategy();
static class SafeFileDeleteStrategy extends FileDeleteStrategy {
protected CopyOnWriteArrayList<String> protectedPaths = new CopyOnWriteArrayList<>();
protected SafeFileDeleteStrategy() {
super("DoNotTouchNuxeoBinaries");
}
protected void registerProtectedPath(String path) {
protectedPaths.add(path);
}
protected boolean isFileProtected(File fileToDelete) {
for (String path : protectedPaths) {
// do not delete files under the protected directories
if (fileToDelete.getPath().startsWith(path)) {
log.warn("Protect file " + fileToDelete.getPath()
+ " from deletion : check usage of Framework.trackFile");
return true;
}
}
return false;
}
@Override
protected boolean doDelete(File fileToDelete) throws IOException {
if (!isFileProtected(fileToDelete)) {
return super.doDelete(fileToDelete);
} else {
return false;
}
}
}
/**
* Registers a protected path under which files should not be deleted
*
* @param path
* @since 7.2
*/
public static void registerProtectedPath(String path) {
deleteStrategy.registerProtectedPath(path);
}
protected class GCDelegate implements FileEventHandler {
protected FileCleaningTracker delegate = new FileCleaningTracker();
@Override
public void onFile(File file, Object marker) {
delegate.track(file, marker, deleteStrategy);
}
}
protected class ThreadDelegate implements FileEventHandler {
protected final boolean isLongRunning;
protected final Thread owner = Thread.currentThread();
protected final Set<File> files = new HashSet<>();
protected ThreadDelegate(boolean isLongRunning) {
this.isLongRunning = isLongRunning;
}
@Override
public void onFile(File file, Object marker) {
if (!owner.equals(Thread.currentThread())) {
return;
}
if (isLongRunning) {
gc.onFile(file, marker);
}
files.add(file);
}
}
@XObject("enableThreadsTracking")
public static class EnableThreadsTracking {
}
protected final GCDelegate gc = new GCDelegate();
protected static FileEventTracker self;
protected final ThreadLocal<ThreadDelegate> threads = new ThreadLocal<>();
protected final ThreadEventListener threadsListener = new ThreadEventListener(new ThreadEventHandler() {
@Override
public void onEnter(boolean isLongRunning) {
setThreadDelegate(isLongRunning);
}
@Override
public void onLeave() {
resetThreadDelegate();
}
});
protected final FileEventListener filesListener = new FileEventListener(new FileEventHandler() {
@Override
public void onFile(File file, Object marker) {
onContext().onFile(file, marker);
}
});
@Override
public void activate(ComponentContext context) {
super.activate(context);
self = this;
filesListener.install();
setThreadDelegate(false);
}
@Override
public int getApplicationStartedOrder() {
return Integer.MAX_VALUE;
}
@Override
public void applicationStarted(ComponentContext context) {
resetThreadDelegate();
}
@Override
public void deactivate(ComponentContext context) {
if (Framework.getService(EventService.class) != null) {
if (threadsListener.isInstalled()) {
threadsListener.uninstall();
}
filesListener.uninstall();
}
self = null;
super.deactivate(context);
}
@Override
public void registerContribution(Object contribution, String extensionPoint, ComponentInstance contributor) {
if (contribution instanceof EnableThreadsTracking) {
threadsListener.install();
} else {
super.registerContribution(contribution, extensionPoint, contributor);
}
}
protected FileEventHandler onContext() {
FileEventHandler actual = threads.get();
if (actual == null) {
actual = gc;
}
return actual;
}
protected void setThreadDelegate(boolean isLongRunning) {
if (threads.get() != null) {
throw new IllegalStateException("Thread delegate already installed");
}
threads.set(new ThreadDelegate(isLongRunning));
}
protected void resetThreadDelegate() throws IllegalStateException {
ThreadDelegate actual = threads.get();
if (actual == null) {
return;
}
try {
for (File file : actual.files) {
if (!deleteStrategy.isFileProtected(file)) {
file.delete();
}
}
} finally {
threads.remove();
}
}
}