/// <summary>
/// Sends the given request. If tracing is initialized and enabled the outgoing request is
/// traced and the trace header is added to the request.
/// </summary>
protected override async Task <HttpResponseMessage> SendAsync(
HttpRequestMessage request, CancellationToken cancellationToken)
{
if (_tracer.GetCurrentTraceId() == null)
{
return(await base.SendAsync(request, cancellationToken).ConfigureAwait(false));
}
var traceHeader = TraceHeaderContext.Create(
_tracer.GetCurrentTraceId(), _tracer.GetCurrentSpanId() ?? 0, true);
request.Headers.Add(TraceHeaderContext.TraceHeader, traceHeader.ToString());
_tracer.StartSpan(request.RequestUri.ToString());
try
{
return(await base.SendAsync(request, cancellationToken).ConfigureAwait(false));
}
catch (Exception e)
{
StackTrace stackTrace = new StackTrace(e, true);
_tracer.SetStackTrace(stackTrace);
throw;
}
finally
{
_tracer.EndSpan();
}
}
/// <summary>
/// Invokes the next <see cref="RequestDelegate"/> and trace the time
/// taken for the next delegate to run, reporting the results to the
/// Stackdriver Trace API.
/// </summary>
public async Task Invoke(HttpContext httpContext, IManagedTracer tracer)
{
GaxPreconditions.CheckNotNull(tracer, nameof(tracer));
if (tracer.GetCurrentTraceId() == null)
{
await _next(httpContext);
}
else
{
// Trace the delegate and annotate it with information from the current
// http context.
tracer.StartSpan(httpContext.Request.Path);
try
{
await _next(httpContext);
}
catch (Exception e)
{
StackTrace stackTrace = new StackTrace(e, true);
tracer.SetStackTrace(stackTrace);
throw;
}
finally
{
tracer.AnnotateSpan(Labels.AgentLabel);
tracer.AnnotateSpan(Labels.FromHttpContext(httpContext));
tracer.EndSpan();
}
}
}
/// <summary>Traces a 10ms sleep and adds a stacktrace.</summary>
public string TraceStackTrace(string id, [FromServices] IManagedTracer tracer)
{
string message = GetMessage(nameof(TraceStackTrace), id);
tracer.StartSpan(message);
Thread.Sleep(10);
tracer.SetStackTrace(CreateStackTrace());
tracer.EndSpan();
return(message);
}
/// <summary>Traces a 10ms sleep and adds a stacktrace.</summary>
public string TraceStackTrace(string id, [FromServices] IManagedTracer tracer)
{
string message = EntryData.GetMessage(nameof(TraceStackTrace), id);
using (tracer.StartSpan(message))
{
Thread.Sleep(10);
tracer.SetStackTrace(TraceEntryData.CreateStackTrace());
}
return(message);
}
