org.apache.tomee.livereload.FileWatcher Maven / Gradle / Ivy
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* 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.tomee.livereload;
import org.apache.johnzon.mapper.Mapper;
import org.apache.openejb.util.LogCategory;
import org.apache.openejb.util.Logger;
import jakarta.websocket.CloseReason;
import jakarta.websocket.Session;
import java.io.Closeable;
import java.io.File;
import java.io.IOException;
import java.nio.file.ClosedWatchServiceException;
import java.nio.file.Path;
import java.nio.file.StandardWatchEventKinds;
import java.nio.file.WatchEvent;
import java.nio.file.WatchKey;
import java.nio.file.WatchService;
import java.util.ArrayList;
import java.util.Collection;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
public class FileWatcher {
private final Logger logger;
private final Mapper mapper;
private final Collection sessions = new ArrayList<>();
public FileWatcher(final LogCategory logger, final Mapper mapper) {
this.logger = Logger.getInstance(logger, FileWatcher.class);
this.mapper = mapper;
}
public synchronized void addSession(final Session session) {
sessions.add(session);
}
public synchronized void removeSession(final Session session) {
sessions.remove(session);
}
public Closeable watch(final String folder) {
final File file = new File(folder);
if (!file.isDirectory()) {
throw new IllegalArgumentException(folder + " is not a directory");
}
try {
final AtomicBoolean again = new AtomicBoolean(true);
final Path path = file.getAbsoluteFile().toPath();
final WatchService watchService = path.getFileSystem().newWatchService();
path.register(watchService, StandardWatchEventKinds.ENTRY_CREATE, StandardWatchEventKinds.ENTRY_DELETE, StandardWatchEventKinds.ENTRY_MODIFY);
final Thread watcherThread = new Thread(new Runnable() {
@Override
public void run() {
while (again.get()) {
try {
final WatchKey key = watchService.poll(1, TimeUnit.SECONDS); // don't use take to not block forever
if (key == null) {
continue;
}
for (final WatchEvent event : key.pollEvents()) {
final WatchEvent.Kind kind = event.kind();
if (kind != StandardWatchEventKinds.ENTRY_CREATE
&& kind != StandardWatchEventKinds.ENTRY_DELETE
&& kind != StandardWatchEventKinds.ENTRY_MODIFY) {
continue;
}
final Path updatedPath = Path.class.cast(event.context());
if (kind == StandardWatchEventKinds.ENTRY_DELETE || updatedPath.toFile().isFile()) {
final String path = updatedPath.toString();
if (path.endsWith("___jb_tmp___") || path.endsWith("___jb_old___")) {
continue;
} else if (path.endsWith("~")) {
onChange(path.replace(File.pathSeparatorChar, '/').substring(0, path.length() - 1));
} else {
onChange(path.replace(File.pathSeparatorChar, '/'));
}
}
}
key.reset();
} catch (final InterruptedException e) {
Thread.interrupted();
again.set(false);
} catch (final ClosedWatchServiceException cwse) {
// ok, we finished there
}
}
}
});
watcherThread.setName("livereload-tomee-watcher(" + folder + ")");
watcherThread.start();
return new Closeable() {
@Override
public void close() throws IOException {
synchronized (this) {
for (final Session s : sessions) {
removeSession(s);
try {
s.close(new CloseReason(CloseReason.CloseCodes.GOING_AWAY, "container shutdowned"));
} catch (final Exception e) {
// ok: not important there
}
}
}
again.compareAndSet(true, false);
try {
watchService.close();
} catch (final IOException ioe) {
logger.warning("Error closing the watch service for " + folder + "(" + ioe.getMessage() + ")");
}
try {
watcherThread.join(TimeUnit.MINUTES.toMillis(1));
} catch (final InterruptedException e) {
Thread.interrupted();
}
}
};
} catch (final IOException e) {
throw new IllegalArgumentException(e);
}
}
private void onChange(final String path) {
final Command command = new Command();
command.setCommand("reload");
command.setPath(path);
command.setLiveCss(true); // TODO: check path to set it to false if not relevant?
final String asStr = mapper.writeObjectAsString(command);
final Collection copy;
synchronized (this) {
copy = new ArrayList<>(this.sessions);
}
int failed = 0;
for (final Session s : copy) {
try {
s.getBasicRemote().sendText(asStr);
} catch (final Exception e) {
logger.warning("Can't send one livereload update: " + e.getMessage());
failed++;
}
}
if (failed < copy.size()) {
logger.info("Updated livereload path: " + path);
}
}
}