private async Task <IList <INumericRangeBlockContext> > GetNumericRangeBlocksAsync(ITaskExecutionContext taskExecutionContext)
{
using (var cs = taskExecutionContext.CreateCriticalSection())
{
if (await cs.TryStartAsync())
{
long startNumber;
var lastBlock = await taskExecutionContext.GetLastNumericRangeBlockAsync(LastBlockOrder.LastCreated);
var maxJourneyId = await _travelDataService.GetMaxJourneyIdAsync();
// if this is the first run then just process the last 1000
if (lastBlock == null)
{
startNumber = maxJourneyId - 1000;
}
// if there is no new data then just return any old blocks that have failed or died
else if (lastBlock.EndNumber == maxJourneyId)
{
return(await taskExecutionContext.GetNumericRangeBlocksAsync(x => x.OnlyOldNumericBlocks()));
}
// startNumber is the next unprocessed id
else
{
startNumber = lastBlock.EndNumber + 1;
}
int maxBlockSize = 500;
return(await taskExecutionContext.GetNumericRangeBlocksAsync(x => x.WithRange(startNumber, maxJourneyId, maxBlockSize)));
}
throw new Exception("Could not acquire a critical section, aborted task");
}
}