Queued Components called from a Web Service

Question

Hello All,

I seem to be having a problem with COM+ that has me stumped.  I'm developing a Queued Component on an x64 Windows 7 box (but I've found the same issue on W2K8R2) with no success.  The component is (supposed to be) instatiated by a web service, but Marshal.GetActiveObject returns null.  I've combed through all the COM+ application settings and the Event Viewer with no luck. 

Here is the code for the web service:

using WCF = global::System.ServiceModel;

namespace WCFService1.ServiceImplementation
{
    using System;
    using System.Diagnostics;
    using System.Runtime.InteropServices;
    using Processor;
    using WCFService1.DataContracts;
    using WCFService1.MessageContracts;

    /// <summary>
    /// Service Class - Service1
    /// </summary>
    [WCF::ServiceBehavior(Name = "Service1",
        Namespace = "http://MSMQDemoR2.Model/2012/ServiceContractDsl1",
        InstanceContextMode = WCF::InstanceContextMode.PerSession,
        ConcurrencyMode = WCF::ConcurrencyMode.Single)]
    public abstract class Service1Base : ServiceContracts.IServiceContract1
    {
        #region ServiceContract1 Members

        public virtual MessageContracts.XsdMessage1 Operation1(MessageContracts.Message1 request)
        {
            return null;
        }

        #endregion ServiceContract1 Members
    }

    public partial class Service1 : Service1Base
    {
        public override MessageContracts.XsdMessage1 Operation1(MessageContracts.Message1 request)
        {
            var res = new XsdMessage1();
            var tRoot = new root() { ExtensionData = null, msg = "sent" };

            try
            {
                var iQc = Marshal.GetActiveObject("queue:/new:{67F00E61-E75E-317E-BAE5-46C76A3F1C73}") as IQComponent;  // THIS RETURNS NULL

                // iQc.DisplayMessage(messageToSend.Text);
                Debug.Assert(iQc != null, "iQc != null");
                iQc.ProcessQueue(msg: "test");
                Marshal.ReleaseComObject(o: iQc);

                tRoot.err = "good";
            }
            catch (Exception ex)
            {
                tRoot.err = ex.ToString();
            }

            res.Root = tRoot;

            return res;
        }
    }
}

Here is the Queued COM Component:

using System;
using System.Data;
using System.Diagnostics;
using System.EnterpriseServices;
using System.Messaging;
using System.Reflection;
using System.Runtime.InteropServices;
using Microsoft.Practices.EnterpriseLibrary.Data;
using Microsoft.Practices.EnterpriseLibrary.Data.Sql;

[assembly: ApplicationName(name: "QueueProcessor")]
[assembly: AssemblyKeyFile(keyFile: "keyPair.snk")]
[assembly: CLSCompliant(true)]
[assembly: ApplicationActivation(ActivationOption.Server)]
[assembly: ApplicationQueuing(Enabled = true, QueueListenerEnabled = true)]
[assembly: ApplicationAccessControl(false)]

namespace Processor
{
    [ComVisible(true)]
    [CLSCompliant(true)]
    [InterfaceQueuing(Enabled = true)]
    public interface IQComponent
    {
        void ProcessQueue(string msg);
    }

    [ComVisible(true)]
    [CLSCompliant(true)]
    [InterfaceQueuing(Interface = "IQComponent")]
    public class MainClass1 : ServicedComponent, IQComponent
    {
        private static readonly log4net.ILog Log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        [ComVisible(true)]
        [CLSCompliant(true)]
        public void ProcessQueue(string msg)
        {
            Debug.Assert(Log != null, "log != null");

            Log.Info(message: "Application [ProcessQueue] Start");
            Log.Debug(message: string.Format(format: "msg:{0}", arg0: msg));

            string tres = string.Empty;

            try
            {
                Log.Debug(message: "starting SQL run");
                Database db = new SqlDatabase("Data Source=PCSOFFDGG;Initial Catalog=testdb;Integrated Security=True");
                db.ExecuteNonQuery(CommandType.Text,
                                   "INSERT INTO results(st,name) SELECT a.st,b.name FROM people b INNER JOIN states AS a ON a.id=b.id");
                using (var tdb = db.ExecuteReader(CommandType.Text, "SELECT * FROM results"))
                    while (tdb.Read())
                    {
                        tres += string.Format("{0}:{1}:{2}", tdb[0], tdb[1], tdb[2]);
                        Log.Debug(message: string.Format(format: "tres:{0}", arg0: tres));
                    }
            }
            catch (Exception ex)
            {
                Log.Error(message: ex);
            }
            Log.Debug(message: "finished SQL run");

            Log.Debug(message: "starting MSMQ run");
            try
            {
                using (var tMessageQueue = new MessageQueue(@".\private$\testa"))
                    tMessageQueue.Send(obj: tres);
                Log.Debug(message: "MSMQ good");
            }
            catch (Exception ex)
            {
                Log.Error(message: ex);
            }
            Log.Debug(message: "end MSMQ run");

            Log.Info("Application [ProcessQueue] End");
        }

        [CLSCompliant(isCompliant: true)]
        public MainClass1()
        {
            Log.Debug("Application [ProcessQueue] Constructor");
        }
    }
}

Thanks in advance for any ideas.

Geoff

Answer 1

Just a quick follow up: I originally tried Marshal.BindToMoniker before trying Marshal.GetActiveObject

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Geoffrey J Gowey