Traces are being recorded for ignored patterns

There is an option to ignore some tracing patterns as described here - #28 Steps to reproduce: 0. Setup: ASP.NET Core 2.2, OpenTracing.Contrib.NetCore 0.5.0

1. Have the following code. MonitoringController.cs

        [HttpGet]
        [Route("health")]
        public IActionResult Health()
        {
            var state = StateManager.CurrentState;
            if (state is State.RequiresRestart)
            {
                this.log.Warning("Health probe was requested, but service is in {State} state", state);
                return this.StatusCode(503);
            }

            return this.Ok();
        }

Startup.cs

            services.AddJaeger().AddOpenTracing(builder =>
                builder.ConfigureAspNetCore(options =>
                {
                    // ignore certain requests to prevent spamming the tracer with irrelevant data
                    options.Hosting.IgnorePatterns.Add(request =>
                        request.Request.Path.Value?.StartsWith("/monitoring") == true);
                }));

1. Call GET /monitoring/health endpoint.

Expected behaviour: No traces were reported for this call. Actual behaviour: Traces were recorded for this call.

So, I went on and fixed it with PR #35 where you can see the reason of this bug.

[tillig]

As noted in my earlier comment

PR #35 looks like it’ll handle the hosting and MVC parts but not the EF bit.

Basically, this fixes one of the issues, but it doesn’t actually enforce it at all levels. So, no, unfortunately the PR didn’t totally resolve this for me.

[cwe1ss]

The new v0.7.0 release now supports this via the options.StartRootSpans property on all Configure*() methods. If ASP.NET Core instrumentation is enabled (which happens automatically when it is an ASP.NET Core application), all other instrumentation is set to StartRootSpans = false. This means that no spans are created if the ASP.NET Core request is ignored via the IgnorePatterns option.

The library still creates spans if running in a regular console application. In that case, you have to configure the library to your liking.