LobbyGrain.cs

namespace MyGrainCollection
{
    using MyGrainInterfaces;
    using Orleans;
    using System;
    using System.Threading.Tasks;

    // [StorageProvider(ProviderName = "AzureTableStorage")]
    [StorageProvider(ProviderName = "BlobStorageProvider")]
    public class LobbyGrain : GrainBase<ILobbyGrainState>, ILobbyGrain
    {
        private readonly PersistencyPolicy policy = PersistencyPolicy.Every(TimeSpan.FromSeconds(10));

        async Task<string> ILobbyGrain.GetQuote()
        {
            this.State.Value++;

            Action log = ((Func<Action>)(() =>
            {
                var logger = this.GetLogger();
                var id = this.GetPrimaryKey();
                return () => logger.Info("Persisted state in grain \"{0}\"", id);
            }))();

            await this.policy.PersistIdNeeded(
                persist: this.State.WriteStateAsync,
                otherAction: log);

            return (this.State.Value).ToString();
        }
    }

    public class PersistencyPolicy
    {
        public static PersistencyPolicy Every(TimeSpan interval)
        {
            return new PersistencyPolicy(interval);
        }

        public PersistencyPolicy(TimeSpan interval)
        {
            this.Interval = interval;
        }

        private TimeSpan Interval { get; set; }

        private DateTimeOffset Last { get; set; }

        private bool ShouldPersist { get { return DateTimeOffset.UtcNow > this.Last.Add(this.Interval); } }

        public async Task PersistIdNeeded(Func<Task> persist, Action otherAction = null)
        {
            if (ShouldPersist)
            {
                await persist();
                this.Last = DateTimeOffset.UtcNow;

                if (otherAction != null)
                {
                    otherAction();
                }
            }
        }
    }
}