/// <summary>
/// Transmits the current contents of the span buffer to the SplunkTracing Collector.
/// Note that this creates a copy of the current spans and clears the span buffer!
/// </summary>
public async void Flush()
{
if (_options.Run)
{
if (_options.EnableMetaEventLogging && _firstReportHasRun == false)
{
BuildSpan(SplunkTracingConstants.MetaEvent.TracerCreateOperation)
.IgnoreActiveSpan()
.WithTag(SplunkTracingConstants.MetaEvent.MetaEventKey, true)
.WithTag(SplunkTracingConstants.MetaEvent.TracerGuidKey, _options.TracerGuid)
.Start()
.Finish();
_firstReportHasRun = true;
}
// save current spans and clear the buffer
ISpanRecorder currentBuffer;
lock (_lock)
{
currentBuffer = _spanRecorder.GetSpanBuffer();
_spanRecorder = new SplunkTracingSpanRecorder();
_logger.Trace($"{currentBuffer.GetSpans().Count()} spans in buffer.");
}
/**
* there are two ways spans can be dropped:
* 1. the buffer drops a span because it's too large, malformed, etc.
* 2. the report failed to be sent to the collector.
* since flush is async and there can potentially be any number of buffers in flight to the collector,
* we need to set the current drop count on the tracer to be the amount of dropped spans from the buffer
* plus the existing dropped spans, then mutate the current buffer to this new total value.
*/
currentDroppedSpanCount += currentBuffer.DroppedSpanCount;
currentBuffer.DroppedSpanCount = currentDroppedSpanCount;
if (currentBuffer.GetSpans().Count() > 0)
{
try
{
// since translate can throw exceptions, place it in the try and drop spans as appropriate
var data = _httpClient.Translate(currentBuffer);
var resp = await _httpClient.SendReport(data);
if (resp.code > 0)
{
_logger.Warn($"Errors in report: {resp.text}");
}
// if the collector is in developer mode, set the tracer to development mode as well
// don't re-enable if it's already enabled though
// TODO: iterate through all commands to find devmode flag
if (_options.EnableMetaEventLogging == false)
{
_logger.Info("Enabling meta event logging");
_options.EnableMetaEventLogging = true;
}
lock (_lock)
{
_logger.Trace($"Resetting tracer dropped span count as the last report was successful.");
currentDroppedSpanCount = 0;
}
}
catch (Exception ex) when(ex is HttpRequestException || ex is TaskCanceledException || ex is OperationCanceledException || ex is Exception)
{
lock (_lock)
{
_logger.Warn($"Adding {currentBuffer.GetSpans().Count()} spans to dropped span count (current total: {currentDroppedSpanCount})");
_logger.Warn($"Exception: {ex}");
currentDroppedSpanCount += currentBuffer.GetSpans().Count();
if (this._options.ExceptionHandlerRegistered)
{
this._options.ExceptionHandler.Invoke(ex);
}
}
}
}
}
}
