public JarvisFrameworkLambdaSubscription(ChunkProcessor fn, String lambdaName)
{
_fn = fn;
_lambdaName = lambdaName;
_failedPosition = 0;
LastException = null;
MetricsHelper.CreateGauge($"fw-lambda-subscription-{_lambdaName}", () => _numOfChunksProcessed, Unit.Items);
}