Finding a renamed notepad process

[bstordrup]

If I provide a copy of the Notepad.exe file with a different name (say MyNotepadMonitor.exe), I can provide a custom Func<Process> that searches for this process name in the call to LoggerConfiguration().WriteTo.Notepad().

But what if I don't use this, but rely entirely on the configuration in appsettings.json? Is it possible to provide a function there? Or would it be an option to add a parameter that specifies the name of the executable to use instead of Notepad.exe?

[augustoproiete]

Hey @bstordrup, the custom Func<Process> would be the way to go in this case. You can store the name of the custom process in
a key you define appsettings.json and use that in your custom func.

{
  "NotepadProcessName": "MyNotepadMonitor"
}

Log.Logger = new LoggerConfiguration()
    .MinimumLevel.Verbose()
    .WriteTo.Notepad(notepadProcessFinderFunc: () =>
    {
        return Process.GetProcessesByName(Configuration["NotepadProcessName"])
            .Where(p => !p.HasExited)
            .OrderByDescending(p => p.StartTime)
            .FirstOrDefault();
    })
    .CreateLogger();

[bstordrup]

Can that approach be used with ReadFromConfigurationmethod?

Log.Logger = new LoggerConfiguration ()
   .ReadFrom.Configuration (configuration)
   .CreateLogger ();

where I have the notepad sink defined in the config file?

My approach right now is to call this function after creating the logger:

        private static void ReplaceNotepadTextWriter ()
        {
            var logger = Log.Logger as Serilog.Core.Logger;

            // Assemblies
            var serilogAssembly = typeof (ILogEventSink).Assembly;
            var notepadLogAssembly = typeof (NotepadWindow).Assembly;

            // Types needed
            var safeAggregateSinkType = serilogAssembly.DefinedTypes.FirstOrDefault (tp => tp.Name == "SafeAggregateSink");

            var notepadSinkType = notepadLogAssembly.DefinedTypes.FirstOrDefault (tp => tp.Name == "NotepadSink");
            var textWriterSinkType = notepadLogAssembly.DefinedTypes.FirstOrDefault (tp => tp.Name == "TextWriterSink");
            var notepadTextWriterType = notepadLogAssembly.DefinedTypes.FirstOrDefault (tp => tp.Name == "NotepadTextWriter");


            // SafeAggregateSink
            var sinkFieldInfo = logger.GetType ().GetNonPublicField ("_sink");
            var sinkValueObject = sinkFieldInfo.GetValue (logger);

            //Serilog.Core.Sinks.SafeAggregateSink
            var sinksFieldInfo = sinkValueObject.GetType ().GetNonPublicField ("_sinks");
            var sinks = sinksFieldInfo.GetValue (sinkValueObject) as ILogEventSink [];

            var notepadSink = sinks.FirstOrDefault (s => s.GetType () == notepadSinkType);
            if (notepadSink != null)
            {
                var formatter = notepadSinkType.BaseType.GetNonPublicField ("_formatter")
                    .GetValue (notepadSink) as ITextFormatter;

                var pos = System.Array.IndexOf (sinks, notepadSink);
                if (pos != -1)
                {
                    var notepadTextWriterConstructor = notepadTextWriterType.GetConstructor (new Type []
                    {
                        typeof(Func<Process>)
                    });
                    var newNotepadTextWriter = notepadTextWriterConstructor.Invoke (new Func<Process> []
                    {
                        TryFindMostRecentNotepadProcessWithSELogParameter
                    });
                    var notepadSinkConstructor = notepadSinkType.GetConstructor (new Type []
                    {
                        notepadTextWriterType,
                        typeof(ITextFormatter),
                        typeof(object)
                    });
                    var newNotepadSink = notepadSinkConstructor.Invoke (new object []
                    {
                        newNotepadTextWriter,
                        formatter,
                        new object()
                    });

                    sinks [pos] = (ILogEventSink) newNotepadSink;
                }
            }
        }