Program.cs

// -----------------------------------------------------------------------
// <copyright file="Program.cs" company="Asynkron AB">
//      Copyright (C) 2015-2024 Asynkron AB All rights reserved
// </copyright>
// -----------------------------------------------------------------------

using System;
using System.Threading;
using System.Threading.Tasks;
using Proto;

namespace ContextDecorators;

public class LoggingRootDecorator : RootContextDecorator
{
    public LoggingRootDecorator(IRootContext context) : base(context)
    {
    }

    public override async Task<T> RequestAsync<T>(PID target, object message, CancellationToken ct)
    {
        Console.WriteLine("Enter RequestAsync");
        var res = await base.RequestAsync<T>(target, message, ct);
        Console.WriteLine("Exit RequestAsync");

        return res;
    }
}

public class LoggingDecorator : ActorContextDecorator
{
    private readonly string _loggerName;

    public LoggingDecorator(IContext context, string loggerName) : base(context)
    {
        _loggerName = loggerName;
    }

    //we are just logging this single method
    public override void Respond(object message)
    {
        Console.WriteLine($"{_loggerName} : Enter Respond");
        base.Respond(message);
        Console.WriteLine($"{_loggerName} : Exit Respond");
    }
}

internal class Program
{
    private static void Main(string[] args)
    {
        var context = new LoggingRootDecorator(new RootContext(new ActorSystem()));

        var props = Props.FromFunc(ctx =>
                    {
                        if (ctx.Message is string str)
                        {
                            Console.WriteLine("Inside Actor: " + str);
                            ctx.Respond("Yo!");
                        }

                        return Task.CompletedTask;
                    }
                )
                .WithContextDecorator(c => new LoggingDecorator(c, "logger1"))
                .WithContextDecorator(c => new LoggingDecorator(c, "logger2"))
            ;

        var pid = context.Spawn(props);
        var res = context.RequestAsync<string>(pid, "Hello").Result;
        Console.WriteLine("Got result " + res);
        Console.ReadLine();
    }
}