aspnetcore/src/Microsoft.AspNet.HttpFeature/Security/ISignInContext.cs

using System.Collections.Generic;
using System.Security.Claims;

namespace Microsoft.AspNet.HttpFeature.Security
{
    public interface ISignInContext
    {
        ClaimsPrincipal User { get; }
        IDictionary<string, string> Properties { get; }

        void Ack(string authenticationType, IDictionary<string, object> description);
    }
}