public async Task <ActionResult <string> > Get(string name, CancellationToken ct)
{
using (IScope scope = _tracer.BuildActiveSpan("Hello-get"))
{
ISpan span = scope.Span;
span.LogMessage("baggage", span.GetBaggageItem("baggage"));
// Here you can have TaskCanceledException, which will be handled by ExceptionHandlingMiddleware.
await Task.Delay(_random.Next(100, 250), ct);
HttpStatusCode selectedStatusCode = _httpStatusCodes[_random.Next(_httpStatusCodes.Length)];
span.LogMessage("name", name);
span.Log($"Selected status code: {selectedStatusCode}");
// --> Return OK.
if (selectedStatusCode == HttpStatusCode.OK)
{
return(Ok($"Hello {name}."));
}
// --> Delay.
if (selectedStatusCode == HttpStatusCode.RequestTimeout)
{
try
{
// If your method do not accept token in the argument, you can check it here beforehand.
ct.ThrowIfCancellationRequested();
await Task.Delay(5000, ct);
}
catch (OperationCanceledException)
{
span.Log("The operation was canceled.");
return(NoContent());
}
// The timeout policy cancel this call earlier, so you won't see this line.
span.Log($"After the delay.");
}
if (selectedStatusCode == HttpStatusCode.InternalServerError)
{
throw new Exception("Throw exception for test purpose.");
}
// --> Other returns.
return(new ContentResult
{
StatusCode = (int)selectedStatusCode,
Content = $"Selected status code: {selectedStatusCode}"
});
}
}
public async Task SayHello(string helloTo)
{
using (IScope scope = _tracer.BuildActiveSpan("Call-web-app")) // BuildActiveSpan: From common extensions.
{
ISpan span = scope.Span;
span.SetBaggageItem("baggage", "baggage-value");
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, $"Hello/{helloTo}");
request.Headers.InjectTracing( // InjectTracing: From common extensions.
request.Method.Method, $"{_httpClient.BaseAddress}{request.RequestUri}");
HttpResponseMessage response = null;
try
{
response = await _httpClient.SendAsync(request);
}
catch (Exception ex)
{
span.LogError(ex, "Failed to call say hello."); // LogError: From common extensions.
Console.WriteLine(ex.Message);
return;
}
span.SetTag(Tags.HttpStatus, (int)response.StatusCode);
string responseString = await response.Content.ReadAsStringAsync();
span.LogMessage("response", responseString); // LogMessage: From common extensions.
Console.WriteLine(responseString);
}
}
public static ISpan LogMessage(this ISpan span, string message) => span.LogMessage(LogFields.Message, message);
