source: branches/HeuristicLab.Hive-3.4/sources/HeuristicLab.Clients.Hive.Slave/3.4/Core.cs @ 6546

#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2011 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Diagnostics;
using System.ServiceModel;
using System.Threading;
using System.Threading.Tasks;
using HeuristicLab.Clients.Hive.SlaveCore.Properties;
using HeuristicLab.Clients.Hive.SlaveCore.ServiceContracts;
using HeuristicLab.Common;
using HeuristicLab.Core;


namespace HeuristicLab.Clients.Hive.SlaveCore {
  /// <summary>
  /// The core component of the Hive Slave. 
  /// Handles commands sent from the Hive Server and does all webservice calls for jobs. 
  /// </summary>
  public class Core : MarshalByRefObject {
    private static HeartbeatManager heartbeatManager;
    public static HeartbeatManager HeartbeatManager {
      get { return heartbeatManager; }
    }

    public EventLog ServiceEventLog { get; set; }

    private Semaphore waitShutdownSem = new Semaphore(0, 1);
    private bool abortRequested;
    private ISlaveCommunication clientCom;
    private ServiceHost slaveComm;
    private WcfService wcfService;
    private JobManager jobManager;
    private ConfigManager configManager;
    private PluginManager pluginManager;

    public Core() {
      var log = new ThreadSafeLog(new Log(Settings.Default.MaxLogCount));
      this.pluginManager = new PluginManager(WcfService.Instance, log);
      this.jobManager = new JobManager(pluginManager, log);
      log.MessageAdded += new EventHandler<EventArgs<string>>(log_MessageAdded);

      RegisterJobManagerEvents();

      this.configManager = new ConfigManager(jobManager);
      ConfigManager.Instance = this.configManager;
    }

    /// <summary>
    /// Main method for the client
    /// </summary>
    public void Start() {
      abortRequested = false;

      try {
        //start the client communication service (pipe between slave and slave gui)
        slaveComm = new ServiceHost(typeof(SlaveCommunicationService));
        slaveComm.Open();
        clientCom = SlaveClientCom.Instance.ClientCom;

        // delete all left over job directories
        pluginManager.CleanPluginTemp();
        clientCom.LogMessage("Hive Slave started");

        wcfService = WcfService.Instance;
        RegisterServiceEvents();

        StartHeartbeats(); // Start heartbeats thread        
        DispatchMessageQueue(); // dispatch messages until abortRequested
      }
      catch (Exception ex) {
        if (ServiceEventLog != null) {
          try {
            ServiceEventLog.WriteEntry(string.Format("Hive Slave threw exception: {0} with stack trace: {1}", ex.ToString(), ex.StackTrace), EventLogEntryType.Error);
          }
          catch (Exception) { }
        } else {
          //try to log with clientCom. if this works the user sees at least a message, 
          //else an exception will be thrown anyways.
          clientCom.LogMessage(string.Format("Uncaught exception: {0} {1} Core is going to shutdown.", ex.ToString(), Environment.NewLine));
        }
        ShutdownCore();
      }
      finally {
        DeregisterServiceEvents();
        waitShutdownSem.Release();
      }
    }

    private void StartHeartbeats() {
      //Initialize the heartbeat     
      if (heartbeatManager == null) {
        heartbeatManager = new HeartbeatManager();
        heartbeatManager.StartHeartbeat();
      }
    }

    private void DispatchMessageQueue() {
      MessageQueue queue = MessageQueue.GetInstance();
      while (!abortRequested) {
        MessageContainer container = queue.GetMessage();
        DetermineAction(container);
        if (!abortRequested) {
          clientCom.StatusChanged(configManager.GetStatusForClientConsole());
        }
      }
    }

    private void RegisterServiceEvents() {
      WcfService.Instance.Connected += new EventHandler(WcfService_Connected);
      WcfService.Instance.ExceptionOccured += new EventHandler<EventArgs<Exception>>(WcfService_ExceptionOccured);
    }

    private void DeregisterServiceEvents() {
      WcfService.Instance.Connected -= WcfService_Connected;
      WcfService.Instance.ExceptionOccured -= WcfService_ExceptionOccured;
    }

    private void WcfService_ExceptionOccured(object sender, EventArgs<Exception> e) {
      clientCom.LogMessage(string.Format("Connection to server interruped with exception: {0}", e.Value.Message));
    }

    private void WcfService_Connected(object sender, EventArgs e) {
      clientCom.LogMessage("Connected successfully to Hive server");
    }

    /// <summary>
    /// Reads and analyzes the Messages from the MessageQueue and starts corresponding actions
    /// </summary>
    /// <param name="container">The container, containing the message</param>
    private void DetermineAction(MessageContainer container) {
      clientCom.LogMessage(string.Format("Message: {0} for job: {1} ", container.Message.ToString(), container.JobId));

      if (container is ExecutorMessageContainer<Guid>) {
        ExecutorMessageContainer<Guid> c = (ExecutorMessageContainer<Guid>)container;
        c.execute();
      } else if (container is MessageContainer) {
        switch (container.Message) {
          case MessageContainer.MessageType.CalculateJob:
            CalculateJobAsync(container.JobId);
            break;
          case MessageContainer.MessageType.AbortJob:
            AbortJobAsync(container.JobId);
            break;
          case MessageContainer.MessageType.StopJob:
            StopJobAsync(container.JobId);
            break;
          case MessageContainer.MessageType.PauseJob:
            PauseJobAsync(container.JobId);
            break;
          case MessageContainer.MessageType.StopAll:
            DoStopAll();
            break;
          case MessageContainer.MessageType.PauseAll:
            DoPauseAll();
            break;
          case MessageContainer.MessageType.AbortAll:
            DoAbortAll();
            break;
          case MessageContainer.MessageType.ShutdownSlave:
            ShutdownCore();
            break;
          case MessageContainer.MessageType.Restart:
            DoStartSlave();
            break;
          case MessageContainer.MessageType.Sleep:
            Sleep();
            break;
          case MessageContainer.MessageType.SayHello:
            wcfService.Connect(configManager.GetClientInfo());
            break;
        }
      } else {
        clientCom.LogMessage("Unknown MessageContainer: " + container);
      }
    }

    private void CalculateJobAsync(Guid jobId) {
      Task.Factory.StartNew(HandleCalculateJob, jobId)
      .ContinueWith((t) => {
        SlaveStatusInfo.IncrementExceptionOccured();
        clientCom.LogMessage(t.Exception.ToString());
      }, TaskContinuationOptions.OnlyOnFaulted);
    }

    private void StopJobAsync(Guid jobId) {
      Task.Factory.StartNew(HandleStopJob, jobId)
       .ContinueWith((t) => {
         SlaveStatusInfo.IncrementExceptionOccured();
         clientCom.LogMessage(t.Exception.ToString());
       }, TaskContinuationOptions.OnlyOnFaulted);
    }

    private void PauseJobAsync(Guid jobId) {
      Task.Factory.StartNew(HandlePauseJob, jobId)
       .ContinueWith((t) => {
         SlaveStatusInfo.IncrementExceptionOccured();
         clientCom.LogMessage(t.Exception.ToString());
       }, TaskContinuationOptions.OnlyOnFaulted);
    }

    private void AbortJobAsync(Guid jobId) {
      Task.Factory.StartNew(HandleAbortJob, jobId)
       .ContinueWith((t) => {
         SlaveStatusInfo.IncrementExceptionOccured();
         clientCom.LogMessage(t.Exception.ToString());
       }, TaskContinuationOptions.OnlyOnFaulted);
    }

    private void HandleCalculateJob(object jobIdObj) {
      Guid jobId = (Guid)jobIdObj;
      Job job = null;
      int usedCores = 0;
      try {
        job = wcfService.GetJob(jobId);
        if (job == null) throw new JobNotFoundException(jobId);
        if (ConfigManager.Instance.GetFreeCores() < job.CoresNeeded) throw new OutOfCoresException();
        if (ConfigManager.GetFreeMemory() < job.MemoryNeeded) throw new OutOfMemoryException();
        SlaveStatusInfo.IncrementUsedCores(job.CoresNeeded); usedCores = job.CoresNeeded;
        JobData jobData = wcfService.GetJobData(jobId);
        if (jobData == null) throw new JobDataNotFoundException(jobId);
        job = wcfService.UpdateJobState(jobId, JobState.Calculating, null);
        if (job == null) throw new JobNotFoundException(jobId);
        jobManager.StartJobAsync(job, jobData);
      }
      catch (JobNotFoundException) {
        SlaveStatusInfo.DecrementUsedCores(usedCores);
        throw;
      }
      catch (JobDataNotFoundException) {
        SlaveStatusInfo.DecrementUsedCores(usedCores);
        throw;
      }
      catch (JobAlreadyRunningException) {
        SlaveStatusInfo.DecrementUsedCores(usedCores);
        throw;
      }
      catch (OutOfCoresException) {
        wcfService.UpdateJobState(jobId, JobState.Waiting, "No more cores available");
        throw;
      }
      catch (OutOfMemoryException) {
        wcfService.UpdateJobState(jobId, JobState.Waiting, "No more memory available");
        throw;
      }
      catch (Exception e) {
        SlaveStatusInfo.DecrementUsedCores(usedCores);
        wcfService.UpdateJobState(jobId, JobState.Waiting, e.ToString()); // unknown internal error - report and set waiting again
        throw;
      }
    }

    private void HandleStopJob(object jobIdObj) {
      Guid jobId = (Guid)jobIdObj;
      try {
        Job job = wcfService.GetJob(jobId);
        if (job == null) throw new JobNotFoundException(jobId);
        jobManager.StopJobAsync(jobId);
      }
      catch (JobNotFoundException) {
        throw;
      }
      catch (JobNotRunningException) {
        throw;
      }
      catch (AppDomainNotCreatedException) {
        throw;
      }
    }

    private void HandlePauseJob(object jobIdObj) {
      Guid jobId = (Guid)jobIdObj;
      try {
        Job job = wcfService.GetJob(jobId);
        if (job == null) throw new JobNotFoundException(jobId);
        jobManager.PauseJobAsync(jobId);
      }
      catch (JobNotFoundException) {
        throw;
      }
      catch (JobNotRunningException) {
        throw;
      }
      catch (AppDomainNotCreatedException) {
        throw;
      }
    }

    private void HandleAbortJob(object jobIdObj) {
      Guid jobId = (Guid)jobIdObj;
      try {
        jobManager.AbortJob(jobId);
      }
      catch (JobNotFoundException) {
        throw;
      }
    }

    #region JobManager Events
    private void RegisterJobManagerEvents() {
      this.jobManager.JobStarted += new EventHandler<EventArgs<SlaveJob>>(jobManager_JobStarted);
      this.jobManager.JobPaused += new EventHandler<EventArgs<SlaveJob, JobData>>(jobManager_JobPaused);
      this.jobManager.JobStopped += new EventHandler<EventArgs<SlaveJob, JobData>>(jobManager_JobStopped);
      this.jobManager.JobFailed += new EventHandler<EventArgs<Tuple<SlaveJob, JobData, Exception>>>(jobManager_JobFailed);
      this.jobManager.ExceptionOccured += new EventHandler<EventArgs<SlaveJob, Exception>>(jobManager_ExceptionOccured);
      this.jobManager.JobAborted += new EventHandler<EventArgs<SlaveJob>>(jobManager_JobAborted);
    }

    private void jobManager_JobStarted(object sender, EventArgs<SlaveJob> e) {
      // successfully started, everything is good
    }

    private void jobManager_JobPaused(object sender, EventArgs<SlaveJob, JobData> e) {
      try {
        SlaveStatusInfo.DecrementUsedCores(e.Value.CoresNeeded);
        heartbeatManager.AwakeHeartBeatThread();
        Job job = wcfService.GetJob(e.Value.JobId);
        if (job == null) throw new JobNotFoundException(e.Value.JobId);
        job.ExecutionTime = e.Value.ExecutionTime;
        JobData jobData = e.Value.GetJobData();
        wcfService.UpdateJobData(job, jobData, configManager.GetClientInfo().Id, JobState.Paused);
      }
      catch (JobNotFoundException ex) {
        clientCom.LogMessage(ex.ToString());
      }
      catch (Exception ex) {
        clientCom.LogMessage(ex.ToString());
      }
    }

    private void jobManager_JobStopped(object sender, EventArgs<SlaveJob, JobData> e) {
      try {
        SlaveStatusInfo.DecrementUsedCores(e.Value.CoresNeeded);
        heartbeatManager.AwakeHeartBeatThread();
        Job job = wcfService.GetJob(e.Value.JobId);
        if (job == null) throw new JobNotFoundException(e.Value.JobId);
        job.ExecutionTime = e.Value.ExecutionTime;
        JobData jobData = e.Value.GetJobData();
        wcfService.UpdateJobData(job, jobData, configManager.GetClientInfo().Id, JobState.Finished);
      }
      catch (JobNotFoundException ex) {
        clientCom.LogMessage(ex.ToString());
      }
      catch (Exception ex) {
        clientCom.LogMessage(ex.ToString());
      }
    }

    private void jobManager_JobFailed(object sender, EventArgs<Tuple<SlaveJob, JobData, Exception>> e) {
      try {
        SlaveStatusInfo.DecrementUsedCores(e.Value.Item1.CoresNeeded);
        heartbeatManager.AwakeHeartBeatThread();
        SlaveJob slaveJob = e.Value.Item1;
        JobData jobData = e.Value.Item2;
        Exception exception = e.Value.Item3;

        Job job = wcfService.GetJob(slaveJob.JobId);
        if (job == null) throw new JobNotFoundException(slaveJob.JobId);
        job.ExecutionTime = slaveJob.ExecutionTime;
        if (jobData != null) {
          wcfService.UpdateJobData(job, jobData, configManager.GetClientInfo().Id, JobState.Failed, exception.ToString());
        } else {
          wcfService.UpdateJobState(job.Id, JobState.Failed, exception.ToString());
        }
        clientCom.LogMessage(exception.Message);
      }
      catch (JobNotFoundException ex) {
        SlaveStatusInfo.IncrementExceptionOccured();
        clientCom.LogMessage(ex.ToString());
      }
      catch (Exception ex) {
        SlaveStatusInfo.IncrementExceptionOccured();
        clientCom.LogMessage(ex.ToString());
      }
    }

    private void jobManager_ExceptionOccured(object sender, EventArgs<SlaveJob, Exception> e) {
      SlaveStatusInfo.DecrementUsedCores(e.Value.CoresNeeded);
      SlaveStatusInfo.IncrementExceptionOccured();
      heartbeatManager.AwakeHeartBeatThread();
      clientCom.LogMessage(string.Format("Exception occured for job {0}: {1}", e.Value.JobId, e.Value2.ToString()));
      wcfService.UpdateJobState(e.Value.JobId, JobState.Waiting, e.Value2.ToString());
    }

    private void jobManager_JobAborted(object sender, EventArgs<SlaveJob> e) {
      SlaveStatusInfo.DecrementUsedCores(e.Value.CoresNeeded);
    }
    #endregion

    #region Log Events
    private void log_MessageAdded(object sender, EventArgs<string> e) {
      clientCom.LogMessage(e.Value.Split('\t')[1]);
    }
    #endregion

    /// <summary>
    /// aborts all running jobs, no results are sent back
    /// </summary>
    private void DoAbortAll() {
      clientCom.LogMessage("Aborting all jobs.");
      foreach (Guid jobId in jobManager.JobIds) {
        AbortJobAsync(jobId);
      }
    }

    /// <summary>
    /// wait for jobs to finish, then pause client
    /// </summary>
    private void DoPauseAll() {
      clientCom.LogMessage("Pausing all jobs.");
      foreach (Guid jobId in jobManager.JobIds) {
        PauseJobAsync(jobId);
      }
    }

    /// <summary>
    /// pause slave immediately
    /// </summary>
    private void DoStopAll() {
      clientCom.LogMessage("Stopping all jobs.");
      foreach (Guid jobId in jobManager.JobIds) {
        StopJobAsync(jobId);
      }
    }

    #region Slave Lifecycle Methods
    /// <summary>
    /// completly shudown slave
    /// </summary>
    public void Shutdown() {
      MessageContainer mc = new MessageContainer(MessageContainer.MessageType.ShutdownSlave);
      MessageQueue.GetInstance().AddMessage(mc);
      waitShutdownSem.WaitOne();
    }

    /// <summary>
    /// complete shutdown, should be called before the the application is exited
    /// </summary>
    private void ShutdownCore() {
      clientCom.LogMessage("Shutdown signal received");
      clientCom.LogMessage("Stopping heartbeat");
      heartbeatManager.StopHeartBeat();
      abortRequested = true;

      DoAbortAll();

      clientCom.LogMessage("Logging out");
      WcfService.Instance.Disconnect();
      clientCom.Shutdown();
      SlaveClientCom.Close();

      if (slaveComm.State != CommunicationState.Closed)
        slaveComm.Close();
    }

    /// <summary>
    /// reinitializes everything and continues operation, 
    /// can be called after Sleep()
    /// </summary>  
    private void DoStartSlave() {
      clientCom.LogMessage("Restart received");
      configManager.Asleep = false;
    }

    /// <summary>
    /// stop slave, except for client gui communication, 
    /// primarily used by gui if core is running as windows service
    /// </summary>    
    private void Sleep() {
      clientCom.LogMessage("Sleep received - not accepting any new jobs");
      configManager.Asleep = true;
      DoPauseAll();
    }
    #endregion
  }
}