private async Task ProcessRequestUser(uint requestId)
{
// this method simulates user code of processing a service request.
// Construct a moniker for displaying:
const string Indent = " ";
string requestMoniker = $"{Indent}[requestTraceId={requestId}]";
for (int i = 0; i < requestId; i++)
{
requestMoniker = Indent + requestMoniker;
}
// Simulate work with several async transitions like one would expect for I/O/
for (int i = 100; i < 110; i++)
{
// This simulates either manual or automatic tracing. I.e., a sub-span is created.
MockSpan prevSpan = _currentSpan.Value;
_currentSpan.Value = new MockSpan(prevSpan.TraceId, (ulong)i);
try
{
Console.WriteLine($"\n{requestMoniker} [i={i}]"
+ $" asLoc=\"{_currentSpan.Value}\";"
// + $" ThrdInfo.State=\"{CurrentThreadInfo.CurrentState}\";"
// + $" ThrdInfo.IsInit={CurrentThreadInfo.IsInitialized};"
+ $" Before Delay: ThreadId={Thread.CurrentThread.ManagedThreadId}.");
await Task.Delay(TimeSpan.FromMilliseconds(500));
Console.WriteLine($"\n{requestMoniker} [i={i}]"
+ $" asLoc=\"{_currentSpan.Value}\";"
// + $" ThrdInfo.State=\"{CurrentThreadInfo.CurrentState}\";"
// + $" ThrdInfo.IsInit={CurrentThreadInfo.IsInitialized};"
+ $" After Delay: ThreadId={Thread.CurrentThread.ManagedThreadId}.");
}
finally
{
_currentSpan.Value = prevSpan;
}
}
}
private async Task ProcessRequestSystem(uint requestId)
{
// This method simulates stuff in the app server..
ulong traceId = requestId; // In reality, obtain traceId from propagated context.
MockSpan rootSpan = new MockSpan(traceId, 0);
MockSpan prevSpanInfo = _currentSpan.Value;
_currentSpan.Value = rootSpan;
try
{
await ProcessRequestUser(requestId);
}
finally
{
_currentSpan.Value = prevSpanInfo;
}
}
/// <summary>
/// Ths callback is invoked by AsyncLocal each time the values changed for an underlying physical managed tread.
/// The tracer must use a collback timilar to this.
/// </summary>
/// <param name="changeInfo"></param>
private static void OnAsyncLocalValueChanged(AsyncLocalValueChangedArgs <MockSpan> changeInfo)
{
MockSpan currenActiveSpan = changeInfo.CurrentValue;
Console.WriteLine($"\n* AsyncLocalValueChanged."
+ $" PrevVal=\"{changeInfo.PreviousValue}\","
+ $" CurrVal=\"{currenActiveSpan}\","
+ $" CtxChange={changeInfo.ThreadContextChanged},"
+ $" ThreadId={Thread.CurrentThread.ManagedThreadId}.");
if (TraceContextTrackerFactory.SingletonInstance.TryGetOrCreateTraceContextTrackerForCurrentThread(out TraceContextTracker tracker))
{
if (currenActiveSpan != null)
{
tracker.TrySetTraceContextInfoForCurrentThread(SpanInfo.ForSpan(currenActiveSpan.TraceId, currenActiveSpan.SpanId));
}
else
{
tracker.TrySetTraceContextInfoForCurrentThread(SpanInfo.ForNoSpan());
}
}
}