using System;

using System.Threading;

using System.Threading.Tasks;

using Polly;

using Polly.Timeout;

using Polly.Retry;

public class Program

{

    public static async Task Main()

    {

        var timeout = Policy.TimeoutAsync(

            timeoutProvider: ctx => 

            {

                var ts = TimeSpan.FromSeconds(Math.Pow(2, ctx.GetAttemptNumber() + 1));

                Console.WriteLine($"New timeout: {ts}");

                return ts;

            }, 

            onTimeoutAsync: (ctx, ts, t) => { Console.WriteLine($"Timeout: {ts}"); return Task.CompletedTask; });

​

        var retry = Policy

            .Handle<TimeoutRejectedException>()

            .WaitAndRetryAsync(

                retryCount: 5, 

                sleepDurationProvider: _ => TimeSpan.FromMilliseconds(100), 

                onRetry: (ex, ts, attemptCount, ctx) => 

                {

                    Console.WriteLine($"Retry after {attemptCount}th attempt");

                    ctx.SetAttemptNumber(attemptCount);

                });

​

        var strategy = Policy.WrapAsync(retry, timeout);

​

        var ctx = new Context();

        await strategy.ExecuteAsync(async (ctx, ct) => {

            Console.WriteLine($"-=< {ctx.GetAttemptNumber()}th attempt >=-");

            Console.WriteLine($"Execution started: {DateTime.UtcNow}");

            await Task.Delay(100_000, ct);

        }, ctx, CancellationToken.None);

​

    }

}

​

public static class ContextExtensions

{

    private static readonly string key = "AttemptNumber";

​

    public static Context SetAttemptNumber(this Context context, int attemptNumber)

    {

        context[key] = attemptNumber;

        return context;

    }

​

    public static int GetAttemptNumber(this Context context)

    {

        context.TryGetValue(key, out object obj);

        return obj is int attemptNumber ? attemptNumber : 0;

    }

}