DataMaintenanceTask.cs :  » Persistence-Frameworks » Ubik » StoresAndStockPricing » ServerTasks » C# / CSharp Open Source

using System;
using System.Collections.Generic;
using System.Text;
using Ubik.Engine.Server;
using Ubik.Engine.Client;
using System.Reflection;
using StoresAndStockPricing.Model;

namespace StoresAndStockPricing.ServerTasks{
  public class DataMaintenanceTask : Ubik.Engine.Server.ServerTask
  {
    public DataMaintenanceTask()
      : base(new TimeSpan(0, 0, 10))
    {
    }

    public override string ToString()
    {
      return DataMaintenanceTaskResources.TaskName;
    }

    protected override void DoWork(Server server)
    {
      if (server == null)
        throw new ArgumentNullException("server");

      LocalEndpoint endpoint = new LocalEndpoint(server);

      List<Assembly> modelAssemblies = new List<Assembly>();
      modelAssemblies.Add(Assembly.Load("StoresAndStockPricing.Model"));

      using (Session session = new Session(endpoint, modelAssemblies))
      {
        IList<DataMaintenanceEvent> waitingEvents;

        using (Transaction txn = session.BeginTransaction())
        {
          waitingEvents = session.Select<DataMaintenanceEvent>(
              "Status = DataMaintenanceEventStatus.Pending && PlannedDateTime <= #"
              + EngineDateTime.UtcNow.ToString() + "#");

          foreach (DataMaintenanceEvent dmEvent in waitingEvents)
          {
            dmEvent.Detected();
          }

          txn.Commit();
        }

        foreach (DataMaintenanceEvent dmEvent in waitingEvents)
        {
          try
          {
            using (Transaction txn = session.BeginTransaction())
            {
              dmEvent.Apply();

              txn.Commit();
            }
          }
          catch (Exception ex)
          {
            // Exceptions thrown from here indicate a server issue, so we will let them propagate
            // and try again once the server is back online.
            using (Transaction txn = session.BeginTransaction())
            {
              dmEvent.RecordFailure(ex);

              txn.Commit();
            }
          }
        }
      }
    }
  }
}