private void CalculateProgressBeforeRead()
{
var start = Progress?.NextIterationStart ?? _context.StartInstant;
var endCutoffInstant = InstantUtils.SecondsAgo(_context.ClockSkewProtectionSeconds);
var minEndInstant = start.Plus(Duration.FromSeconds(_context.MinIntervalSeconds));
var maxEndInstant = start.Plus(Duration.FromSeconds(_context.MaxIntervalSeconds));
var end = Progress?.NextIterationEnd ?? maxEndInstant;
if (end > maxEndInstant)
{
end = maxEndInstant;
}
if (end > endCutoffInstant)
{
end = endCutoffInstant;
}
if (end < minEndInstant)
{
end = minEndInstant;
}
// Fix the iteration based on _context.End only if the _context.End is between progress start and end
// (so that the iteration needs to be run partially). We don't need to consider any other cases, if
// the Progress.end is passed _context.end, we won't run the iteration anyway.
if (_context.EndInstant.HasValue &&
start < _context.EndInstant.Value &&
end > _context.EndInstant.Value)
{
end = _context.EndInstant.Value;
}
Progress = new JobProgress(start, end, Progress?.NextToken);
}
private JobProgress CalculateProgressAfterRead()
{
// There's no need to consider _context.End here. We just calculate the prospective next iteration span
// and it will be looked at and fixed before the next iteration, if needed.
if (!string.IsNullOrWhiteSpace(_readResponse.NextToken))
{
return(new JobProgress(Progress.NextIterationStart, Progress.NextIterationEnd, _readResponse.NextToken));
}
// If the current timespan is completed, we start from one millisecond after the end of this timespan
// because AWS APIs accept milliseconds as timespan, so the resolution is 1 ms. And the API is
// inclusive for both start and end, so we don't want events with timestamp equal to previous end
// be returned twice.
var start = Progress.NextIterationEnd.Plus(Duration.FromMilliseconds(1));
var endCutoffInstant = InstantUtils.SecondsAgo(_context.ClockSkewProtectionSeconds);
var minEndInstant = start.Plus(Duration.FromSeconds(_context.MinIntervalSeconds));
var maxEndInstant = start.Plus(Duration.FromSeconds(_context.MaxIntervalSeconds));
if (minEndInstant > endCutoffInstant)
{
return(new JobProgress(start, minEndInstant, null));
}
var end = maxEndInstant;
if (end > endCutoffInstant)
{
end = endCutoffInstant;
}
return(new JobProgress(start, end, null));
}
private static Instant?ParseAbsoluteOrRelativeTime(string absoluteTime, int?relativeTimeSecondsAgo)
{
if (!string.IsNullOrWhiteSpace(absoluteTime))
{
var parsedTime = InstantPattern.Parse(absoluteTime);
if (!parsedTime.Success)
{
throw new ArgumentException($"Time pattern '{absoluteTime}' could not be parsed. ISO-8601 based UTC format without fractions of second is expected.");
}
return(parsedTime.Value);
}
if (relativeTimeSecondsAgo.HasValue)
{
return(InstantUtils.SecondsAgo(relativeTimeSecondsAgo.Value));
}
return(null);
}
private bool IsRunnable(JobProgress progress)
{
if (_context.EndInstant.HasValue)
{
// Just check for the end. If this would have been a partial iteration (_context.End was between
// Progress.Start and Progress.End), CalculateProgressBeforeRead method would have been adjusted it.
if (progress.NextIterationEnd > _context.EndInstant.Value)
{
return(false);
}
// If the Progress.End is exactly equal to _context.End, allow it to be run without any regard
// to cut-off, since it's the last iteration ever to be run.
if (progress.NextIterationEnd == _context.EndInstant.Value)
{
return(true);
}
}
var endCutoffInstant = InstantUtils.SecondsAgo(_context.ClockSkewProtectionSeconds);
return(progress.NextIterationEnd <= endCutoffInstant);
}