implementing DynamicProxy in .NET

proxy.cs

using ConsoleTest.Repos;
using Goodreads;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Runtime.Remoting.Messaging;
using System.Runtime.Remoting.Proxies;
using System.Security.Principal;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;

namespace ConsoleTest
{
    class DynamicProxy<T> : RealProxy
    {
        private readonly T _decorated;
        public DynamicProxy(T decorated) : base(typeof(T))
        {
            _decorated = decorated;
        }
        void Log(string msg, object args = null)
        {
            Console.ForegroundColor = ConsoleColor.Red;
            Console.WriteLine(msg, args);
            Console.ResetColor();
        }
        public override IMessage Invoke(IMessage msg)
        {
            var methodCall = msg as IMethodCallMessage;
            var methodInfo = methodCall.MethodBase as MethodInfo;
            Log($"In dynamic proxy - Before executing {methodCall.MethodName}");

            try
            {
                var result = methodInfo.Invoke(_decorated, methodCall.Args);
                Log($"In dynamic proxy - After executing {methodCall.MethodName}");
                return new ReturnMessage(result, null, 0, methodCall.LogicalCallContext, methodCall);
            }
            catch (Exception e)
            {
                Log($"In Dynamic Proxy- Exception {e} executing '{methodCall.MethodName}'");
                return new ReturnMessage(e, methodCall);
            }
        }
    }

    class AuthenticationProxy<T> : RealProxy
    {
        private readonly T _decorated;
        public AuthenticationProxy(T decorated)
          : base(typeof(T))
        {
            _decorated = decorated;
        }
        private void Log(string msg, object arg = null)
        {
            Console.ForegroundColor = ConsoleColor.Green;
            Console.WriteLine(msg, arg);
            Console.ResetColor();
        }
        public override IMessage Invoke(IMessage msg)
        {
            var methodCall = msg as IMethodCallMessage;
            var methodInfo = methodCall.MethodBase as MethodInfo;
            if (Thread.CurrentPrincipal.IsInRole("ADMIN"))
            {
                try
                {
                    Log("User authenticated - You can execute '{0}' ",
                      methodCall.MethodName);
                    var result = methodInfo.Invoke(_decorated, methodCall.InArgs);
                    return new ReturnMessage(result, null, 0,
                      methodCall.LogicalCallContext, methodCall);
                }
                catch (Exception e)
                {
                    Log(string.Format(
                      "User authenticated - Exception {0} executing '{1}'", e),
                      methodCall.MethodName);
                    return new ReturnMessage(e, methodCall);
                }
            }
            Log("User not authenticated - You can't execute '{0}' ",
              methodCall.MethodName);
            return new ReturnMessage(null, null, 0,
              methodCall.LogicalCallContext, methodCall);
        }
    }

    class Program
    {
        Task<string> GetName() => Task.Run(() => "foo");


        async Task<string> GetName2() => "foo";

        static void Main(string[] args)
        {
            Console.WriteLine("***\r\n Begin program - logging and authentication\r\n");
            Console.WriteLine("\r\nRunning as admin");
            Thread.CurrentPrincipal = new GenericPrincipal(new GenericIdentity("Administrator"), new[] { "ADMIN" });
            IRepository<Customer> customerRepository = RepositoryFactory.Create<Customer>();

            var customer = new Customer
            {
                Id = 1,
                Name = "Mahinor",
                Address = "Earth"
            };
            customerRepository.Add(customer);
            customerRepository.Update(customer);
            customerRepository.Delete(customer);
            Console.WriteLine("\r\nRunning as user");
            Thread.CurrentPrincipal = new GenericPrincipal(new GenericIdentity("NormalUser"), new string[] { });
            customerRepository.Add(customer);
            customerRepository.Update(customer);
            customerRepository.Delete(customer);
            Console.WriteLine("\r\nEnd program - logging and authentication\r\n***");
            Console.ReadLine();

        }
    }
}