void IAsyncLogProviderCommandHandler.ContinueAsynchronously(CommandContext ctx)
{
result = new DateBoundPositionResponseData();
result.Position = PositionedMessagesUtils.LocateDateBound(ctx.Reader, date, bound, ctx.Cancellation);
ctx.Tracer.Info("Position to return: {0}", result.Position);
if (result.Position == ctx.Reader.EndPosition)
{
result.IsEndPosition = true;
ctx.Tracer.Info("It is END position");
}
else if (result.Position == ctx.Reader.BeginPosition - 1)
{
result.IsBeforeBeginPosition = true;
ctx.Tracer.Info("It is BEGIN-1 position");
}
else
{
ctx.Cancellation.ThrowIfCancellationRequested();
if (userNeedsDate)
{
result.Date = PositionedMessagesUtils.ReadNearestMessageTimestamp(ctx.Reader, result.Position);
ctx.Tracer.Info("Date to return: {0}", result.Date);
}
}
dateBoundsCache.Set(date, result);
}
async Task IAsyncLogProviderCommandHandler.ContinueAsynchronously(CommandContext ctx)
{
result = new DateBoundPositionResponseData();
result.Position = await PositionedMessagesUtils.LocateDateBound(ctx.Reader, date, bound, ctx.Cancellation);
ctx.Tracer.Info("Position to return: {0}", result.Position);
if (result.Position == ctx.Reader.EndPosition)
{
result.IsEndPosition = true;
ctx.Tracer.Info("It is END position");
}
else if (result.Position == ctx.Reader.BeginPosition - 1)
{
result.IsBeforeBeginPosition = true;
ctx.Tracer.Info("It is BEGIN-1 position");
}
else
{
ctx.Cancellation.ThrowIfCancellationRequested();
if (messageRequested)
{
result.Message = await PositionedMessagesUtils.ReadNearestMessage(ctx.Reader, result.Position, MessagesParserFlag.HintMessageContentIsNotNeeed);
ctx.Tracer.Info("Details to return: {0} at {1}", result.Message?.Time, result.Message?.Position);
}
}
dateBoundsCache.Set(date, result);
}
public bool Update()
{
using (owner.trace.NewNamedFrame("Updating {0}", this.fileName))
{
CheckDisposed();
try
{
if (simpleMedia == null)
{
owner.trace.Info("SimpleMedia object not created yet. Creating");
simpleMedia = new SimpleFileMedia(
owner.fileSystem,
SimpleFileMedia.CreateConnectionParamsFromFileName(Path.Combine(owner.baseDirectory, FileName))
);
}
owner.trace.Info("Updating simple media");
simpleMedia.Update();
if (!simpleMedia.IsAvailable)
{
owner.trace.Info("File is not avaliable (i.e. has been deleted)");
return(false);
}
if (firstMessageTime == null)
{
owner.trace.Info("First message time is unknown. Calcalating it");
using (IPositionedMessagesReader reader = (IPositionedMessagesReader)Activator.CreateInstance(
owner.logReaderType, new MediaBasedReaderParams(owner.tempThreads, SimpleMedia, owner.tempFilesManager), owner.logFormatInfo))
{
owner.trace.Info("Reader created");
reader.UpdateAvailableBounds(false);
owner.trace.Info("Bounds found");
IMessage first = PositionedMessagesUtils.ReadNearestMessage(reader, reader.BeginPosition);
if (first == null)
{
owner.trace.Warning("No messages found");
return(false);
}
owner.trace.Info("First message: {0} '{1}'", first.Time, first.Text);
firstMessageTime = first.Time;
}
}
owner.trace.Info("Part updated OK");
return(true);
}
catch (Exception e)
{
owner.trace.Error(e, "Failure during part update");
return(false);
}
}
}
bool UpdateAvailableTime(bool incrementalMode)
{
bool itIsFirstUpdate = firstUpdateFlag;
firstUpdateFlag = false;
UpdateBoundsStatus status = reader.UpdateAvailableBounds(incrementalMode);
if (status == UpdateBoundsStatus.NothingUpdated && incrementalMode)
{
return(false);
}
if (status == UpdateBoundsStatus.OldMessagesAreInvalid)
{
incrementalMode = false;
}
// Get new boundary values into temporary variables
IMessage newFirst, newLast;
PositionedMessagesUtils.GetBoundaryMessages(reader, null, out newFirst, out newLast);
if (firstMessage != null)
{
if (newFirst == null || MessageTimestamp.Compare(newFirst.Time, firstMessage.Time) != 0)
{
// The first message we've just read differs from the cached one.
// This means that the log was overwritten. Fall to non-incremental mode.
incrementalMode = false;
}
}
if (!incrementalMode)
{
if (!itIsFirstUpdate)
{
// Reset everything that has been loaded so far
InvalidateEverythingThatHasBeenLoaded();
}
firstMessage = null;
}
// Try to get the dates range for new bounday messages
DateRange newAvailTime = GetAvailableDateRangeHelper(newFirst, newLast);
firstMessage = newFirst;
// Getting here means that the boundaries changed.
// Fire the notfication.
var positionsRange = new FileRange.Range(reader.BeginPosition, reader.EndPosition);
if (!incrementalMode)
{
readerContentsEtag = reader.GetContentsEtag();
}
int contentsEtag =
readerContentsEtag
^ positionsRange.Begin.GetHashCode()
^ positionsRange.End.GetHashCode();
StatsTransaction(stats =>
{
stats.AvailableTime = newAvailTime;
LogProviderStatsFlag f = LogProviderStatsFlag.AvailableTime;
if (incrementalMode)
{
f |= LogProviderStatsFlag.AvailableTimeUpdatedIncrementallyFlag;
}
stats.TotalBytes = reader.SizeInBytes;
f |= LogProviderStatsFlag.BytesCount;
stats.PositionsRange = positionsRange;
f |= LogProviderStatsFlag.PositionsRange;
stats.PositionsRangeUpdatesCount++;
if (stats.ContentsEtag == null || contentsEtag != stats.ContentsEtag.Value)
{
stats.ContentsEtag = contentsEtag;
f |= LogProviderStatsFlag.ContentsEtag;
}
return(f);
});
return(true);
}