internal static IGroupGrain GetGroupGrain(this IGrainFactory factory, string hubName, string groupName) => factory.GetGrain <IGroupGrain>(ConnectionGrainKey.Build(hubName, groupName));
internal static IUserGrain GetUserGrain(this IGrainFactory factory, string hubName, string userId) => factory.GetGrain <IUserGrain>(ConnectionGrainKey.Build(hubName, userId));
internal static IClientGrain GetClientGrain(this IGrainFactory factory, string hubName, string connectionId) => factory.GetGrain <IClientGrain>(ConnectionGrainKey.Build(hubName, connectionId));