source: branches/HiveStatistics/sources/HeuristicLab.Services.Hive/3.3/Manager/NewEventManager.cs @ 12789

using System;
using System.Linq;
using HeuristicLab.Services.Hive.DataAccess;
using HeuristicLab.Services.Hive.DataAccess.Interfaces;

namespace HeuristicLab.Services.Hive.Manager {
  public class NewEventManager : IEventManager {
    private const string SlaveTimeout = "Slave timed out.";
    private IPersistenceManager PersistenceManager {
      get { return ServiceLocator.Instance.PersistenceManager; }
    }
    private IAuthorizationManager AuthorizationManager {
      get { return ServiceLocator.Instance.AuthorizationManager; }
    }
    private ILogger Log {
      get { return LogFactory.GetLogger(this.GetType().Namespace); }
    }

    public void Cleanup() {
      using (var pm = PersistenceManager) {
        // same transactions as the old EventManager
        pm.UseTransaction(() => {
          SetTimeoutSlavesOffline(pm);
          SetTimeoutTasksWaiting(pm);
          DeleteObsoleteSlaves(pm);
          pm.SubmitChanges();
        });

        pm.UseTransaction(() => {
          FinishParentTasks(pm);
          pm.SubmitChanges();
        });
      }
    }

    /// <summary>
    /// Searches for slaves which are timed out, puts them and their task offline
    /// </summary>
    private void SetTimeoutSlavesOffline(IPersistenceManager pm) {
      var slaveDao = pm.SlaveDao;
      var slaves = slaveDao.GetOnlineSlaves();
      foreach (var slave in slaves) {
        if (!slave.LastHeartbeat.HasValue ||
            (DateTime.Now - slave.LastHeartbeat.Value) >
            HeuristicLab.Services.Hive.Properties.Settings.Default.SlaveHeartbeatTimeout) {
          slave.SlaveState = SlaveState.Offline;
        }
      }
    }

    /// <summary>
    /// Looks for parent tasks which have FinishWhenChildJobsFinished and set their state to finished
    /// </summary>
    private void FinishParentTasks(IPersistenceManager pm) {
      var resourceDao = pm.ResourceDao;
      var taskDao = pm.TaskDao;
      var resourceIds = resourceDao.GetAll().Select(x => x.ResourceId).ToList();
      var parentTasksToFinish = taskDao.GetParentTasks(resourceIds, 0, true);
      foreach (var task in parentTasksToFinish) {
        task.State = TaskState.Finished;
        task.StateLogs.Add(new StateLog {
          State = task.State,
          SlaveId = null,
          UserId = null,
          Exception = string.Empty,
          DateTime = DateTime.Now
        });
      }
    }

    /// <summary>
    /// Looks for task which have not sent heartbeats for some time and reschedules them for calculation
    /// </summary>
    private void SetTimeoutTasksWaiting(IPersistenceManager pm) {
      var taskDao = pm.TaskDao;
      var tasks = taskDao.GetAll().Where(x => (x.State == TaskState.Calculating && (DateTime.Now - x.LastHeartbeat) > HeuristicLab.Services.Hive.Properties.Settings.Default.CalculatingJobHeartbeatTimeout)
                                           || (x.State == TaskState.Transferring && (DateTime.Now - x.LastHeartbeat) > HeuristicLab.Services.Hive.Properties.Settings.Default.TransferringJobHeartbeatTimeout));
      foreach (var task in tasks) {
        task.State = TaskState.Waiting;
        task.StateLogs.Add(new StateLog {
          State = task.State,
          SlaveId = null,
          UserId = null,
          Exception = SlaveTimeout,
          DateTime = DateTime.Now
        });
        task.Command = null;
      }
    }

    /// <summary>
    /// Searches for slaves that are disposable and deletes them if they were offline for too long
    /// </summary>
    private void DeleteObsoleteSlaves(IPersistenceManager pm) {
      var slaveDao = pm.SlaveDao;
      var downtimeDao = pm.DowntimeDao;
      var slaveIds = slaveDao.GetAll()
        .Where(x => x.IsDisposable.GetValueOrDefault()
                 && x.SlaveState == SlaveState.Offline
                 && (DateTime.Now - x.LastHeartbeat) > Hive.Properties.Settings.Default.SweepInterval)
        .Select(x => x.ResourceId)
        .ToList();
      foreach (var id in slaveIds) {
        bool downtimesAvailable = downtimeDao.GetByResourceId(id).Any();
        if (!downtimesAvailable) {
          slaveDao.Delete(id);
        }
      }
    }
  }
}