package fr.in2p3.jsaga.adaptor.job;
   
   import org.apache.log4j.Logger;
   import org.globus.gram.*;
   import org.ietf.jgss.GSSCredential;
   import org.ietf.jgss.GSSException;
   import org.ogf.saga.error.NoSuccessException;
   
   import java.util.Timer;
  import java.util.TimerTask;
  
  /* ***************************************************
   * *** Centre de Calcul de l'IN2P3 - Lyon (France) ***
   * ***             http://cc.in2p3.fr/             ***
   * ***************************************************
   * File:   LCGCEJobMonitorWatchdog
   * Author: Sylvain Reynaud (sreynaud@in2p3.fr)
   * Date:   24 juin 2010
   * ***************************************************
   * Description:                                      */
  /**
   * todo: notify several JobService instances connected to the same LCG-CE with a single grid-monitor ?
   * -> if several JobService instances in the same JVM ?     (yes: submit job with 'ps | grep dest-url')
   * -> if several JobService instances in separate JVMs ?    (no)
   * -> if several JobService instances on separate hosts ?   (no)
   */
  public class LCGCEJobMonitorWatchdog extends TimerTask {
      private static final String RSL = "&(executable = /opt/globus/libexec/grid_monitor_lite.sh)" +
              "(arguments = '--dest-url=https://134.158.71.194:9000/dev/stdout')";
      private static final int WATCHDOG_PERIOD = 5*60*1000;
  
      private static Logger s_logger = Logger.getLogger(LCGCEJobMonitorListener.class);
  
      private GramJob m_gridMonitorJob;
      private String m_serverUrl;
      private Timer m_timer;
  
      public LCGCEJobMonitorWatchdog(GSSCredential cred, String host, int port) throws NoSuccessException {
          m_gridMonitorJob = new GramJob(cred, RSL);
          m_serverUrl = host+":"+port+"/jobmanager-fork";
  
          // start grid monitor
          this.startMonitor();
  
          // start watchdog
          m_timer = new Timer();
          m_timer.schedule(this, WATCHDOG_PERIOD, WATCHDOG_PERIOD);
      }
  
      public void stopAll() throws NoSuccessException {
          // stop watchdog
          m_timer.cancel();
  
          // stop grid monitor
          this.stopMonitor();
      }
  
      public void run() {
          try {
              if (this.isStopped()) {
                  this.startMonitor();
              } else {
                  s_logger.info("Grid monitor is alived: "+m_gridMonitorJob.getIDAsString());
              }
          } catch (NoSuccessException e) {
              s_logger.warn("Failed to start grid monitor", e);
          }
      }
  
      private void startMonitor() throws NoSuccessException {
          try {
              Gram.request(m_serverUrl, m_gridMonitorJob, false);
              s_logger.info("Started grid monitor: "+m_gridMonitorJob.getIDAsString());
          } catch (GramException e) {
              throw new NoSuccessException(e);
          } catch (GSSException e) {
              throw new NoSuccessException(e);
          }
      }
  
      private void stopMonitor() throws NoSuccessException {
          try {
              Gram.cancel(m_gridMonitorJob);
              s_logger.info("Stopped grid monitor: "+m_gridMonitorJob.getIDAsString());
          } catch (GramException e) {
              throw new NoSuccessException(e);
          } catch (GSSException e) {
              throw new NoSuccessException(e);
          }
      }
  
      private boolean isStopped() throws NoSuccessException {
          try {
              Gram.jobStatus(m_gridMonitorJob);
          } catch (GramException e) {
              if (e.getErrorCode() == GramException.ERROR_CONTACTING_JOB_MANAGER) {
                  return true;    // job manager is stopped when status is DONE
              } else {
                  throw new NoSuccessException(e);
             }
         } catch (GSSException e) {
             throw new NoSuccessException(e);
         }
         switch (m_gridMonitorJob.getStatus()) {
             case GramJob.STATUS_DONE:
             case GramJob.STATUS_FAILED:
                 return true;
             default:
                 return false;
         }
     }
 }