com.github.triceo.robozonky.app.configuration.daemon.SuddenDeathDetection Maven / Gradle / Ivy
/*
* Copyright 2017 The RoboZonky Project
*
* 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 com.github.triceo.robozonky.app.configuration.daemon;
import java.time.OffsetDateTime;
import java.time.temporal.ChronoUnit;
import java.time.temporal.TemporalAmount;
import java.util.Arrays;
import java.util.Collection;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicBoolean;
import com.github.triceo.robozonky.internal.api.Settings;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* For whatever reason, if the marketplace stops being repeatedly checked, the robot is effectively dead. And we can
* not get any reasonable logs, since we usually find out days after this has happened.
*
* This little piece of code is designed to detect such a situation. Surrounding code will then take this and kill
* the robot, sending a warning e-mail. When that happens, we will have up-to-date logs and will be able to identify
* the culprit.
*/
class SuddenDeathDetection implements Runnable {
private static final Logger LOGGER = LoggerFactory.getLogger(SuddenDeathDetection.class);
private final Collection daemonsToWatch;
private final CountDownLatch daemonStopsIfReleased;
private final AtomicBoolean suddenDeath = new AtomicBoolean(false);
private final TemporalAmount inactivityThreshold;
public SuddenDeathDetection(final CountDownLatch daemonStopsIfReleased, final Daemon... daemons) {
this(daemonStopsIfReleased, Settings.INSTANCE.getSuddenDeathDelay(), daemons);
}
public SuddenDeathDetection(final CountDownLatch daemonStopsIfReleased, final TemporalAmount inactivityThreshold,
final Daemon... daemons) {
this.daemonsToWatch = Arrays.asList(daemons);
this.daemonStopsIfReleased = daemonStopsIfReleased;
this.inactivityThreshold = inactivityThreshold;
LOGGER.debug("Sudden death threshold is {} seconds.", inactivityThreshold.get(ChronoUnit.SECONDS));
}
private boolean isDead(final Daemon daemon) {
final OffsetDateTime now = OffsetDateTime.now();
final OffsetDateTime lastRefresh = daemon.getLastRunDateTime();
if (lastRefresh == null) {
return false;
} else {
return daemon.getLastRunDateTime().plus(inactivityThreshold).isBefore(now);
}
}
public Collection getDaemonsToWatch() {
return daemonsToWatch;
}
public boolean isSuddenDeath() {
return suddenDeath.get();
}
@Override
public void run() {
try {
for (final Daemon d : daemonsToWatch) {
if (isDead(d)) {
SuddenDeathDetection.LOGGER.error("Sudden death is here: {}.", d);
suddenDeath.set(true); // make the rest of the code notice the sudden death
daemonStopsIfReleased.countDown(); // kill daemon and report
break;
}
}
} catch (final Throwable t) { // not catching here would stop the thread, disabling sudden death detection
SuddenDeathDetection.LOGGER.warn("Sudden death workaround error.", t);
}
if (suddenDeath.get()) {
throw new IllegalStateException("Sudden death, no need to keep running this thread.");
}
}
}