Bug Report

List of NuGet packages and version that you are using:

• OpenTelemetry.Shims.OpenTracing 1.0.0-rc8
• OpenTelemetry.Extensions.Hosting 1.0.0-rc8
• OpenTelemetry.Exporter.OpenTelemetryProtocol 1.2.0-rc1
• OpenTracing.Contrib.NetCore 0.8.0

Runtime version: netcoreapp3.1

Symptom

We are using our own instrumentations/diagnostics to build spans for specific activities. Static TracerShim:

var openTelemetry = Sdk.CreateTracerProviderBuilder()
                .AddSource("Test.Tracing")
                .SetResourceBuilder(ResourceBuilder.CreateDefault()
                    .AddService(serviceName: "Test_ServiceName", serviceVersion: "Test_Version"))
                .AddOtlpExporter(opt =>
                {
                    opt.Endpoint = new Uri(INTERNAL_URI);
                    opt.Headers = "TOKEN=INTERNAL_TOKEN";
                })
                .Build();

            return new TracerShim(openTelemetry.GetTracer("Test.Tracing"), Propagators.DefaultTextMapPropagator);
        }

Custom diagnostics:

case "Microsoft.AspNetCore.Mvc.BeforeAction":
                    {
                        var httpContext = (HttpContext)_BeforeActionHttpContextFetcher.Fetch(untypedArg);
                        var request = httpContext.Request;
                        ISpanContext extractedSpanContext =  Tracer.Extract(BuiltinFormats.HttpHeaders,
                                new RequestHeadersExtractAdapter(request.Headers));

                        var operationName = _Options.Hosting.HttpOperationNameResolver(httpContext);
                        var actionScope = Tracer.BuildSpan(operationName)
                            .AsChildOf(extractedSpanContext)
                            .WithTag(TracingTags.HttpMethod, request.Method)
                            .WithTag(TracingTags.SpanKind, TracingTags.SpanKindServer)
                            .WithTag(TracingTags.Scheme, request.Scheme)
                            .WithTag(TracingTags.Path, request.Path.Value)
                            .WithTag(TracingTags.Host, request.Host.Value) 
                            .StartActive();

                        httpContext.Items[ActionScopeItemsKey] = actionScope;
                    }
                    break;

What is the expected behavior? The generated span will have valid spanContext in SpanContextShim. And related spans can be created successfully.

What is the actual behavior? The span contains empty fields for context which will cause Passed span's context is not valid ArgumentException when build other child spans for other activities. And no span get created successfully.

Printed span info:

"rootSpan": {
  "context": {
   "spanContext": {
    "traceId": {},
    "spanId": {},
    "traceFlags": 0,
    "isRemote": false,
    "isValid": true,
    "traceState": []
   },
   "traceId": "0828ca1eb896547a61504c4ffcfbd397",
   "spanId": "84647169dea59879"
  }
...
 }

Reproduce

Since we are leveraging same design as OpenTracing.Contrib.NetCore, we can use the project directly with opentelemetry-dotnet/examples/AspNetCore for reproducing the issue. <PackageReference Include="OpenTracing.Contrib.NetCore" Version="0.8.0" />

In Startup.cs:

services.AddOpenTelemetryTracing((builder) => builder
                    .AddSource("Test.Tracing")
                    .SetResourceBuilder(ResourceBuilder.CreateDefault()
                        .AddService(serviceName: "test-name", serviceVersion: "test-version"))
                    .AddOtlpExporter(opt =>
                    {
                        opt.Endpoint = new Uri(INTERNAL_URI);
                        opt.Headers = "TOKEN=INTERNAL_TOKEN";
                    })
            );
            services.AddSingleton<ITracer>(provider =>
            {
                var traceProvider = provider.GetRequiredService<TracerProvider>();
                var tracer = traceProvider.GetTracer("Test.Tracing");
                var tracerShim = new TracerShim(tracer, Propagators.DefaultTextMapPropagator);
                GlobalTracer.Register(tracerShim);
                return tracerShim;
            });
            services.AddOpenTracing();

Warning when running the program:

warn: OpenTracing.Contrib.NetCore.AspNetCore.AspNetCoreDiagnostics[0]
      Event-Exception: Microsoft.AspNetCore.Mvc.BeforeActionResult
System.ArgumentException: Passed span's context is not valid (Parameter 'Context')
   at OpenTelemetry.Shims.OpenTracing.SpanShim..ctor(TelemetrySpan span)
   at OpenTelemetry.Shims.OpenTracing.SpanBuilderShim.Start()
   at OpenTelemetry.Shims.OpenTracing.SpanBuilderShim.StartActive(Boolean finishSpanOnDispose)
   at OpenTelemetry.Shims.OpenTracing.SpanBuilderShim.StartActive()
   at OpenTracing.Contrib.NetCore.AspNetCore.AspNetCoreDiagnostics.HandleEvent(String eventName, Object untypedArg)
   at OpenTracing.Contrib.NetCore.Internal.DiagnosticEventObserver.System.IObserver<System.Collections.Generic.KeyValuePair<System.String,System.Object>>.OnNext(KeyValuePair`2 value)

Additional Context

• We are sending data to Lighstep with internal configuration.

• Also because of https://github.com/open-telemetry/opentelemetry-dotnet/issues/2257 we cannot create any span within the application, for example create span in Controller.