protected virtual async Task DoClose(SourceConnectionClient connection)
        {
            await connection.Stream.FlushAsync().ConfigureAwait(false);

            connection.Dispose();
            Logger.Debug("closed");
            this.Status = ConnectionStatus.Error;
        }
 protected virtual async Task DoClose(SourceConnectionClient connection)
 {
   await connection.Stream.FlushAsync();
   connection.Dispose();
   Logger.Debug("closed");
   this.Status = ConnectionStatus.Error;
 }