public IDisposable DisableAllCaching()
{
return(databaseCommands.DisableAllCaching());
}
private RangeValue GetNextRange(IDatabaseCommands databaseCommands)
{
#if !DNXCORE50
using (new TransactionScope(TransactionScopeOption.Suppress))
using (RavenTransactionAccessor.SupressExplicitRavenTransaction())
#endif
using (databaseCommands.ForceReadFromMaster())
using (databaseCommands.DisableAllCaching())
{
// we need the latest value of the capacity
var calculatedCapacity = Interlocked.Read(ref capacity);
ModifyCapacityIfRequired(ref calculatedCapacity);
while (true)
{
try
{
var minNextMax = Range.Max;
JsonDocument document;
try
{
document = GetDocument(databaseCommands);
}
catch (ConflictException e)
{
// resolving the conflict by selecting the highest number
var highestMax = e.ConflictedVersionIds
.Select(conflictedVersionId => GetMaxFromDocument(databaseCommands.Get(conflictedVersionId), minNextMax, calculatedCapacity))
.Max();
PutDocument(databaseCommands, new JsonDocument
{
Etag = e.Etag,
Metadata = new RavenJObject(),
DataAsJson = RavenJObject.FromObject(new { Max = highestMax }),
Key = HiLoDocumentKey
});
continue;
}
IncreaseCapacityIfRequired(ref calculatedCapacity);
long min, max;
if (document == null)
{
min = minNextMax + 1;
max = minNextMax + calculatedCapacity;
document = new JsonDocument
{
Etag = Etag.Empty,
// sending empty etag means - ensure the that the document does NOT exists
Metadata = new RavenJObject(),
DataAsJson = RavenJObject.FromObject(new { Max = max }),
Key = HiLoDocumentKey
};
}
else
{
var oldMax = GetMaxFromDocument(document, minNextMax, calculatedCapacity);
min = oldMax + 1;
max = oldMax + calculatedCapacity;
document.DataAsJson["Max"] = max;
}
PutDocument(databaseCommands, document);
return(new RangeValue(min, max));
}
catch (ConcurrencyException)
{
// expected, we need to retry
// we'll try to increase the capacity
ModifyCapacityIfRequired(ref calculatedCapacity);
}
}
}
}
