Innovenergy_trunk/csharp/lib/Utils/Try/Operators.async.cs

namespace InnovEnergy.Lib.Utils.Try;


public partial class TryAsync<R>
{
    public TryAsync<R> Retry(Int32 nTimes)
    {
        return Retry<Exception>(nTimes);
    }

    public TryAsync<R> Retry<E>(Int32 nTimes) where E:Exception
    {
        Task<Boolean> ShouldRetry(E _) => Task.FromResult(nTimes-- > 0);

        return Retry<E>(ShouldRetry);
    }

    public TryAsync<R> ExponentialBackoff(TimeSpan initialDelay,
        Int32 nAttempts,
        Double jitterRatio = 0.1)
    {
        Boolean YesToAll(Exception _) => true;

        return ExponentialBackoff<Exception>(YesToAll, initialDelay, nAttempts, jitterRatio);
    }


    public TryAsync<R> ExponentialBackoff<E>(TimeSpan initialDelay,
        Int32 nAttempts,
        Double jitterRatio = 0.1) where E : Exception
    {
        if (jitterRatio is < 0 or > 1)
            throw new ArgumentException(nameof(jitterRatio));

        var delay = initialDelay;

        async Task<Boolean> ShouldRetry(E exception)
        {
            if (nAttempts-- > 0)
            {
                delay = delay.ApplyJitter(jitterRatio);
                await Task.Delay(delay);
                delay *= 2;
                return true;
            }

            return false;
        }

        return Retry<E>(ShouldRetry);
    }


    public TryAsync<R> ExponentialBackoff<E>(Func<E, Boolean> shouldRetry,
        TimeSpan initialDelay,
        Int32 nAttempts,
        Double jitterRatio = 0.1) where E : Exception
    {
        if (jitterRatio is < 0 or > 1)
            throw new ArgumentException(nameof(jitterRatio));

        var delay = initialDelay;

        async Task<Boolean> ShouldRetry(E exception)
        {
            if (nAttempts-- > 0 && shouldRetry(exception))
            {
                delay = delay.ApplyJitter(jitterRatio);
                await Task.Delay(delay);
                delay *= 2;
                return true;
            }

            return false;
        }

        return Retry<E>(ShouldRetry);
    }
}