Java tutorial
/* * The MIT License * * Copyright (c) 2004-, Kohsuke Kawaguchi, Sun Microsystems, Inc., and a number of other of contributors * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package hudson.plugins.ec2; import com.amazonaws.AmazonClientException; import hudson.model.Descriptor; import hudson.slaves.RetentionStrategy; import hudson.util.TimeUnit2; import java.util.concurrent.TimeUnit; import java.util.concurrent.locks.ReentrantLock; import java.util.logging.Logger; import org.apache.commons.lang.math.NumberUtils; import org.kohsuke.stapler.DataBoundConstructor; /** * {@link RetentionStrategy} for EC2. * * @author Kohsuke Kawaguchi */ public class EC2RetentionStrategy extends RetentionStrategy<EC2Computer> { private static final Logger LOGGER = Logger.getLogger(EC2RetentionStrategy.class.getName()); public static final boolean DISABLED = Boolean.getBoolean(EC2RetentionStrategy.class.getName() + ".disabled"); /** * Number of minutes of idleness before an instance should be terminated. A value of zero indicates that the * instance should never be automatically terminated. Negative values are times in remaining minutes before end of * billing period. */ public final int idleTerminationMinutes; private transient ReentrantLock checkLock; private static final int STARTUP_TIME_DEFAULT_VALUE = 30; //ec2 instances charged by hour, time less than 1 hour is acceptable private static final int STARTUP_TIMEOUT = NumberUtils .toInt(System.getProperty(EC2RetentionStrategy.class.getCanonicalName() + ".startupTimeout", String.valueOf(STARTUP_TIME_DEFAULT_VALUE)), STARTUP_TIME_DEFAULT_VALUE); @DataBoundConstructor public EC2RetentionStrategy(String idleTerminationMinutes) { readResolve(); if (idleTerminationMinutes == null || idleTerminationMinutes.trim().isEmpty()) { this.idleTerminationMinutes = 0; } else { int value = STARTUP_TIME_DEFAULT_VALUE; try { value = Integer.parseInt(idleTerminationMinutes); } catch (NumberFormatException nfe) { LOGGER.info("Malformed default idleTermination value: " + idleTerminationMinutes); } this.idleTerminationMinutes = value; } } @Override public long check(EC2Computer c) { if (!checkLock.tryLock()) { return 1; } else { try { return internalCheck(c); } finally { checkLock.unlock(); } } } private long internalCheck(EC2Computer computer) { /* * If we've been told never to terminate, or node is null(deleted), no checks to perform */ if (idleTerminationMinutes == 0 || computer.getNode() == null) { return 1; } if (computer.isIdle() && !DISABLED) { final long uptime; try { uptime = computer.getUptime(); } catch (AmazonClientException | InterruptedException e) { // We'll just retry next time we test for idleness. LOGGER.fine("Exception while checking host uptime for " + computer.getName() + ", will retry next check. Exception: " + e); return 1; } //on rare occasions, AWS may return fault instance which shows running in AWS console but can not be connected. //need terminate such fault instance by {@link #STARTUP_TIMEOUT} if (computer.isOffline() && uptime < TimeUnit2.MINUTES.toMillis(STARTUP_TIMEOUT)) { return 1; } final long idleMilliseconds = System.currentTimeMillis() - computer.getIdleStartMilliseconds(); if (idleTerminationMinutes > 0) { // TODO: really think about the right strategy here, see // JENKINS-23792 if (idleMilliseconds > TimeUnit2.MINUTES.toMillis(idleTerminationMinutes)) { LOGGER.info("Idle timeout of " + computer.getName() + " after " + TimeUnit2.MILLISECONDS.toMinutes(idleMilliseconds) + " idle minutes"); computer.getNode().idleTimeout(); } } else { final int freeSecondsLeft = (60 * 60) - (int) (TimeUnit2.SECONDS.convert(uptime, TimeUnit2.MILLISECONDS) % (60 * 60)); // if we have less "free" (aka already paid for) time left than // our idle time, stop/terminate the instance // See JENKINS-23821 if (freeSecondsLeft <= TimeUnit.MINUTES.toSeconds(Math.abs(idleTerminationMinutes))) { LOGGER.info("Idle timeout of " + computer.getName() + " after " + TimeUnit2.MILLISECONDS.toMinutes(idleMilliseconds) + " idle minutes, with " + TimeUnit2.MILLISECONDS.toMinutes(freeSecondsLeft) + " minutes remaining in billing period"); computer.getNode().idleTimeout(); } } } return 1; } /** * Try to connect to it ASAP. */ @Override public void start(EC2Computer c) { LOGGER.info("Start requested for " + c.getName()); c.connect(false); } // no registration since this retention strategy is used only for EC2 nodes // that we provision automatically. // @Extension public static class DescriptorImpl extends Descriptor<RetentionStrategy<?>> { @Override public String getDisplayName() { return "EC2"; } } protected Object readResolve() { checkLock = new ReentrantLock(false); return this; } }