public async Task RunGcAsync(CancellationToken cancellationToken)
{
_logger.LogInformation("Start GC");
await _tsdb.RunGarbageCollectionInXTableAsync(cancellationToken);
_logger.LogInformation("GC completed");
}
public async Task RunMainLoopAsync(CancellationToken cancellationToken)
{
DateTimeOffset lastAccess;
while (!cancellationToken.IsCancellationRequested)
{
// For long-run, token will self-refresh.
if (DateTimeOffset.Now - _lastLogin > LoginValidity)
{
_logger.LogInformation("Refresh MW token");
// 3 retries with some cool-down period
IPrincipal principal = null;
for (int i = 0; i < 3; i++)
{
principal = await RefreshSessionAsync();
if (principal == null)
{
_logger.LogWarning("MW Failed to log in; retries after 20s");
await Task.Delay(TimeSpan.FromSeconds(20), cancellationToken);
}
else
{
break;
}
}
if (principal == null)
{
_logger.LogError("MW failed to log in; worker exit");
return;
}
}
// Also run GC periodically
if (DateTimeOffset.Now - _lastGcRun > TimeSpan.FromDays(14))
{
try
{
await _tsdb.RunGarbageCollectionInXTableAsync(cancellationToken);
_lastGcRun = DateTimeOffset.Now;
}
catch (Exception exc)
{
_logger.LogError(exc, "Failed to run TS GC");
}
}
// Get last access time stamp from database
lastAccess = _stateRepo.Get <DateTimeOffset>(nameof(lastAccess));
var currentTime = DateTimeOffset.Now;
List <ContentPageChangeEventArgs> changeLists = null;
try
{
changeLists = await _apiSvc.GetRecentChangesSinceAsync(lastAccess);
}
catch (Exception exc)
{
_logger.LogError(exc, "MW failed to retrieve recent changes");
_telemetryClient.TrackException(exc, new Dictionary <string, string>
{
{ "Category", "GetRecentChangesSinceAsync" }
});
await Task.Delay(TimeSpan.FromSeconds(15), cancellationToken);
continue;
}
_logger.LogInformation($"{changeLists.Count} item(s) retrieved");
_telemetryClient.TrackEvent("NewItemIngestion", null, new Dictionary <string, double>
{
{ "Count", changeLists.Count }
});
// Update time stamp if new item retrieved
if (changeLists.Count > 0)
{
lastAccess = currentTime;
_stateRepo.Put(nameof(lastAccess), lastAccess);
}
// Enqueue update events into message topics, send in batch manner
var clusteredUpdates = changeLists.Where(i => i.Title != null).GroupBy(i => i.Title);
var updateMessages = new List <Message>();
foreach (var updateSeries in clusteredUpdates)
{
var sortedSeries = updateSeries.OrderByDescending(i => i.ChangesetId);
var topItem = sortedSeries.First();
var memoryStream = new MemoryStream();
_formatter.Serialize(memoryStream, topItem);
updateMessages.Add(new Message(memoryStream.GetBuffer()));
if (updateMessages.Count > 50)
{
await SendBatchMessagesWithRetry(updateMessages);
updateMessages.Clear();
}
}
// Final one in message bus
await SendBatchMessagesWithRetry(updateMessages);
updateMessages.Clear();
// Ingest edit stats into TS
try
{
var tsSamples = changeLists.Where(g => g.User != null).Select(k => new ContribSampleEntity(k.User, k.EventTimeStamp, 1));
await _tsdb.IngestSamplesAsync(tsSamples.ToList(), cancellationToken);
}
catch (Exception exc)
{
_logger.LogError(exc, "TS failed to ingest edits");
}
// Flush TSDB cache every hour
if (DateTimeOffset.Now - _lastCacheFlush >= TimeSpan.FromHours(1))
{
await _tsdb.FlushCacheAsync(cancellationToken);
_lastCacheFlush = DateTimeOffset.Now;
}
await Task.Delay(TimeSpan.FromSeconds(15), cancellationToken);
}
// Flush local TSDB cache
await _tsdb.FlushCacheAsync(default(CancellationToken));
}
