Problem writing to a custom event log

Problem writing to a custom event log

• llively

  1. This section of code is in my constructor:
  
  System.Diagnostics.EventLog.DeleteEventSource("Smart EmailForwarder"); //I do this because an event source is automatically created in the Application Log by default
  
  if (!System.Diagnostics.EventLog.SourceExists("Smart EmailForwarder"))
  {
  System.Diagnostics.EventLog.CreateEventSource("Smart EmailForwarder",
  "SmartLogs");
  Specify the event log to use your service application as source
  
  }
  SmartLog.Source = "Smart EmailForwarder";
  
  
  2. Method call to write to the custom event log:
  
  WriteToEventLog("Smart Email Forwarder Service Stopped", EventLogEntryType.Information);
  
  
  3. Method used to write to custom log:
  
  public void WriteToEventLog(string sEventLogEntry, EventLogEntryType EventType)
  {
  SmartLog.WriteEntry(sEventLogEntry, EventType);
  }
  
  
  
  
  

• NicS

  Could you post the code you are using to write to the event log I believe the problem lies in the fact that you are calling an overload that is assuming that you are passing it a message ID rather than a string message so it can't find the message resource and is generating the above error.

  Michael Taylor - 10/23/06

  
  

• Steve Hempen

  Your code worked fine for me. You might have some legacy information installed from a previous run. Use the registry editor to clean up any event sources and logs and then try reinstalling your service (you might have to reboot if you deleted any registry keys).

  The event sources are HKLM\System\CurrentControlSet\EventLog.

  Michael Taylor - 11/9/06

  
  

• MS_ISV

  I'm getting a similar problem as the original poster.
  I've tried everything recommended here, but I'm still getting the same errors logged to the Application log. If I don't attempt to use a custom log, then everything works fine. As soon as I try to associate my source to a custom log, I get errors.
  
  I set the Log property of the EventLogInstaller within the ServiceInstaller class. I then also set the Log property of the EventLog in my ServiceBase class. Still doesn't work. I tried deleting the source and recreating it. Doesn't work. I have no idea what else to do.... any help would be greatly appreciated.
  
  -Mark-
  
  
  

• Oliviero_83

  Excellent! Deleting the registry keys and rebooting seems to have worked.
  
  However, it's now logging messages twice, which I need to track down. In any case, thanks for your help!
  
  -Mark-
  
  
  

• dsani

  Can you post your code from your service and from the installer so we can take a look at it

  Michael Taylor - 11/9/06

  
  

• glok

  I see. Your service name is Smart EmailForwarder so when the service installs it automatically creates the source and the association to the Application log. You want to redirect it to a custom log. The problem is that you are trying to delete the default source and use a new source/log instead.

  The issue becomes how to map the source to a new log. You should do this during installation. The problem is that the service installer will create the necessary event log installer logic automatically. Therefore you need to force a change in the log name after the installer is created but before it is installed. Reflection would work here but there is an easier way.

  Within ServiceInstaller is the EventLogInstaller that is used to create the event source/log. The problem is that it is private. However in order for the installer to work properly it must be added to the list of installers. It is added as a child of ServiceInstaller. ServiceInstaller itself is a child installer of ServiceProcessInstaller. Therefore you can write a function to enumerate the installers that will be run and find the event log. You can then modify the log it will write to. Here is some sample code to get you started.

  public ProjectInstaller()
  {
  InitializeComponent();
  
  EventLogInstaller inst = FindEventLogInstaller(this.Installers);
  if (inst != null)
  {
  inst.Log = "CustomLog";
  };
  }

  private EventLogInstaller FindEventLogInstaller(InstallerCollection installers)
  {
  foreach (Installer inst in installers)
  {
  if (inst is EventLogInstaller)
  return (EventLogInstaller)inst;
  
  if (inst.Installers != null)
  {
  EventLogInstaller instLog = FindEventLogInstaller(inst.Installers);
  if (instLog != null)
  return instLog;
  };
  };
  
  return null;
  }

  Remove all the event source delete/create stuff from your constructor and simply use the EventLog property provided by the base class.

  public Service1()
  {
  InitializeComponent();
  
  EventLog.Log = "CustomLog";
  
  EventLog.WriteEntry("Testing", EventLogEntryType.Information);
  }

  It would have been nice if MS had exposed an option off of ServiceInstaller to set the log name like they did for the source but alas they didn't. The class is not sealed so you can actually write an enhanced version that does this for you. The only issue is the fact that the event log installer is still hidden. Therefore you'll still have to enumerate the child installers of the service installer but it'll be quicker. Here is some sample code.
  
  public class ServiceInstallerEx : ServiceInstaller
  {
  public string LogName
  {
  get { return LogInstaller.Log; }
  set { LogInstaller.Log = value; }
  }
  
  private EventLogInstaller LogInstaller
  {
  get
  {
  if (m_installerLog == null)
  {
  foreach (Installer inst in Installers)
  {
  if (inst is EventLogInstaller)
  {
  m_installerLog = (EventLogInstaller)inst;
  break;
  };
  };
  };
  
  return m_installerLog;
  }
  }

  private EventLogInstaller m_installerLog;
  }
  

  Now you don't have to modify the ServiceProcessInstaller code at all other than to use ServiceInstallerEx rather than ServiceInstaller. You can then use the property window to set the custom log option. You'll still need to point the service's EventLog property to your custom log but other than that it works as expected.

  Michael Taylor - 10/25/06

  
  

• pavvu_kk

  Sure....
  
  Here's the code for the installer class:
  
  [RunInstallerAttribute(true)]
  public class InstallerInfo : Installer
  {
  private ServiceInstaller serviceInstaller;
  private ServiceProcessInstaller processInstaller;
  private EventLogInstaller logInstaller;
  
  public InstallerInfo()
  {
  // Instantiate installers for process and services.
  processInstaller = new ServiceProcessInstaller();
  serviceInstaller = new ServiceInstaller();
  
  // The services are started manually.
  serviceInstaller.StartType = ServiceStartMode.Manual;
  
  serviceInstaller.ServiceName = "SunGard Agent";
  
  logInstaller = FindLogInstaller( serviceInstaller.Installers );
  if( logInstaller != null )
  logInstaller.Log = "SunGardEXP";
  
  Installers.Add( serviceInstaller );
  Installers.Add( processInstaller );
  }
  
  EventLogInstaller FindLogInstaller( InstallerCollection installers )
  {
  foreach( Installer installer in installers )
  {
  if( installer is EventLogInstaller )
  return (EventLogInstaller)installer;
  }
  
  return null;
  }
  
  public string ServiceName
  {
  get { return serviceInstaller.ServiceName; }
  set
  {
  serviceInstaller.ServiceName = value;
  logInstaller.Source = value;
  }
  }
  }
  
  The name of the service gets changed to "Agent_fw5" before the installers are run.
  In the constructor of my service class, I had the following line:
  
  this.EventLog.Log = "SunGardEXP";
  
  And to do the logging, I do the following (no need to know what the various parameters to the String.Format are):
  
  eventLog.WriteEntry( String.Format( "[{0}] {1}: {2}", level.ToString(), context.ToString(), message.ToString() ), type );
  
  I also tried the example code on this page: http://quickstart.developerfusion.co.uk/QuickStart/howto/doc/LogWrite.aspx
  
  Using the line (based on code compiled from the above page):
  LogWriter SunGardEXP "Test" "Agent_fw5"
  it works fine before the service is installed. Once the service is installed, logging simple doesn't work for that source anymore.
  
  -Mark-
  
  
  

• Noral

  Hi All,

  This installer thing helped me too get rid of the complex event viewer related problems..... But like mark said I was also finding 2 messages in event viewer..........

  The solution is to set

  this.AutoLog = false;

  AutoLog is a property of Servicebase class

  This will solve all problems on versions like 2k3, xp etc if you have followed method suggested by taylor, so that OS does not interfere with your writing of messages into event viewer.

  
  

• cedubose

  I tried the solution presented by TaylorMichaelL however, it did not work for me. The solution that I came up with is much simpler.
  
  In the project installer for the Service, in ServiceInstaller override the OnAfterInstall subroutine.
  
  Add a line to create a new event source, and then write an entry to it.
  
  The source and log will be created.
  
  Here is the code which was added:
  
  

  Code Block

  Protected Overrides Sub OnAfterInstall(ByVal savedState As System.Collections.IDictionary)
  MyBase.OnAfterInstall(savedState)
  
  If Not EventLog.SourceExists("NewSourceName") Then
  EventLog.CreateEventSource("NewSourceName", "LogName")
  End If
  EventLog.WriteEntry("NewSourceName", "NewSourceName Service Installed")
  End Sub

  
  

  Also, if you want to make sure that the eventsource is created in the proper log, you can use this code:
  
  

  Code Block

  Protected Overrides Sub OnAfterInstall(ByVal savedState As System.Collections.IDictionary)

  MyBase.OnAfterInstall(savedState)
  If EventLog.SourceExists("NewSourceName") Then
  EventLog.DeleteEventSource("NewSourceName")
  End If
  EventLog.CreateEventSource("NewSourceName", "LogName")
  EventLog.WriteEntry("NewSourceName", "NewSourceName Service Installed")
  End Sub

  
  
  

  
  
• Problem writing to a custom event log