org.apache.tika.server.ServerStatusWatcher Maven / Gradle / Ivy
/*
* 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.tika.server;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.time.Duration;
import java.time.Instant;
public class ServerStatusWatcher implements Runnable {
private static final Logger LOG = LoggerFactory.getLogger(ServerStatusWatcher.class);
private final ServerStatus serverStatus;
private final DataInputStream fromParent;
private final DataOutputStream toParent;
private final long maxFiles;
private final ServerTimeouts serverTimeouts;
private volatile Instant lastPing = null;
public ServerStatusWatcher(ServerStatus serverStatus,
InputStream inputStream, OutputStream outputStream,
long maxFiles,
ServerTimeouts serverTimeouts) {
this.serverStatus = serverStatus;
this.maxFiles = maxFiles;
this.serverTimeouts = serverTimeouts;
this.fromParent = new DataInputStream(inputStream);
this.toParent = new DataOutputStream(outputStream);
Thread statusWatcher = new Thread(new StatusWatcher());
statusWatcher.setDaemon(true);
statusWatcher.start();
}
@Override
public void run() {
//let parent know child is alive
try {
toParent.writeByte(ServerStatus.STATUS.OPERATING.getByte());
toParent.flush();
} catch (Exception e) {
LOG.warn("Exception writing startup ping to parent", e);
serverStatus.setStatus(ServerStatus.STATUS.PARENT_EXCEPTION);
shutdown(ServerStatus.STATUS.PARENT_EXCEPTION);
}
byte directive = (byte)-1;
while (true) {
try {
directive = fromParent.readByte();
lastPing = Instant.now();
} catch (Exception e) {
LOG.warn("Exception reading from parent", e);
serverStatus.setStatus(ServerStatus.STATUS.PARENT_EXCEPTION);
shutdown(ServerStatus.STATUS.PARENT_EXCEPTION);
}
if (directive == ServerStatus.DIRECTIVES.PING.getByte()) {
if (serverStatus.getStatus().equals(ServerStatus.STATUS.OPERATING)) {
checkForHitMaxFiles();
checkForTaskTimeouts();
}
try {
toParent.writeByte(serverStatus.getStatus().getByte());
toParent.flush();
} catch (Exception e) {
LOG.warn("Exception writing to parent", e);
serverStatus.setStatus(ServerStatus.STATUS.PARENT_EXCEPTION);
shutdown(ServerStatus.STATUS.PARENT_EXCEPTION);
}
} else if (directive == ServerStatus.DIRECTIVES.SHUTDOWN.getByte()) {
LOG.info("Parent requested shutdown");
serverStatus.setStatus(ServerStatus.STATUS.PARENT_REQUESTED_SHUTDOWN);
shutdown(ServerStatus.STATUS.PARENT_REQUESTED_SHUTDOWN);
} else if (directive == ServerStatus.DIRECTIVES.PING_ACTIVE_SERVER_TASKS.getByte()) { try {
toParent.writeInt(serverStatus.getTasks().size());
toParent.flush();
} catch (Exception e) {
LOG.warn("Exception writing to parent", e);
serverStatus.setStatus(ServerStatus.STATUS.PARENT_EXCEPTION);
shutdown(ServerStatus.STATUS.PARENT_EXCEPTION);
}
}
}
}
private void checkForHitMaxFiles() {
if (maxFiles < 0) {
return;
}
long filesProcessed = serverStatus.getFilesProcessed();
if (filesProcessed >= maxFiles) {
serverStatus.setStatus(ServerStatus.STATUS.HIT_MAX);
}
}
private void checkForTaskTimeouts() {
Instant now = Instant.now();
for (TaskStatus status : serverStatus.getTasks().values()) {
long millisElapsed = Duration.between(status.started, now).toMillis();
if (millisElapsed > serverTimeouts.getTaskTimeoutMillis()) {
serverStatus.setStatus(ServerStatus.STATUS.TIMEOUT);
if (status.fileName.isPresent()) {
LOG.error("Timeout task {}, millis elapsed {}, file {}",
status.task.toString(), Long.toString(millisElapsed), status.fileName.get());
} else {
LOG.error("Timeout task {}, millis elapsed {}",
status.task.toString(), Long.toString(millisElapsed));
}
}
}
}
private void shutdown(ServerStatus.STATUS status) {
LOG.info("Shutting down child process with status: " +status.name());
System.exit(status.getShutdownCode());
}
//This is an internal thread that pulses every 100MS
//within the child to see if the child should die.
private class StatusWatcher implements Runnable {
@Override
public void run() {
while (true) {
ServerStatus.STATUS currStatus = serverStatus.getStatus();
if (currStatus != ServerStatus.STATUS.OPERATING) {
LOG.warn("child process observed "+currStatus.name()+ " and is shutting down.");
shutdown(currStatus);
}
if (lastPing != null) {
long elapsed = Duration.between(lastPing, Instant.now()).toMillis();
if (elapsed > serverTimeouts.getPingTimeoutMillis()) {
serverStatus.setStatus(ServerStatus.STATUS.PARENT_EXCEPTION);
shutdown(ServerStatus.STATUS.PARENT_EXCEPTION);
}
}
try {
Thread.sleep(serverTimeouts.getPingPulseMillis());
} catch (InterruptedException e) {
return;
}
}
}
}
}