Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.reef.poison.context;
020
021import org.apache.reef.evaluator.context.events.ContextStart;
022import org.apache.reef.poison.PoisonException;
023import org.apache.reef.poison.PoisonedAlarmHandler;
024import org.apache.reef.poison.params.CrashProbability;
025import org.apache.reef.poison.params.CrashTimeout;
026import org.apache.reef.tang.annotations.Parameter;
027import org.apache.reef.wake.EventHandler;
028import org.apache.reef.wake.time.Clock;
029
030import javax.inject.Inject;
031import java.util.Random;
032import java.util.logging.Level;
033import java.util.logging.Logger;
034
035/**
036 * Fault-injected handler for ContextStart.
037 */
038public final class PoisonedContextStartHandler implements EventHandler<ContextStart> {
039
040  private static final Logger LOG = Logger.getLogger(PoisonedContextStartHandler.class.getName());
041
042  private final Random random = new Random();
043
044  private final double crashProbability;
045  private final int timeOut;
046  private final Clock clock;
047
048  @Inject
049  public PoisonedContextStartHandler(
050      @Parameter(CrashProbability.class) final double crashProbability,
051      @Parameter(CrashTimeout.class) final int timeOut,
052      final Clock clock) {
053
054    this.crashProbability = crashProbability;
055    this.timeOut = timeOut;
056    this.clock = clock;
057  }
058
059  @Override
060  public void onNext(final ContextStart contextStart) {
061
062    LOG.log(Level.INFO, "Starting Context poison injector with prescribed dose: {0} units",
063        this.crashProbability);
064
065    if (this.random.nextDouble() <= this.crashProbability) {
066
067      final int timeToCrash = this.random.nextInt(this.timeOut) * 1000;
068      LOG.log(Level.INFO, "Dosage lethal! Crashing in {0} msec.", timeToCrash);
069
070      if (timeToCrash == 0) {
071        throw new PoisonException("Crashed at: " + System.currentTimeMillis());
072      } else {
073        this.clock.scheduleAlarm(timeToCrash, new PoisonedAlarmHandler());
074      }
075
076    } else {
077      LOG.info("Dosage not lethal");
078    }
079  }
080}