Set some default trace parameters

tracing/tracing.go

@@ -14,7 +14,9 @@ import (
 	othttp "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/exporters/zipkin"
+	"go.opentelemetry.io/otel/sdk/resource"
 	"go.opentelemetry.io/otel/sdk/trace"
+	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
 	apitrace "go.opentelemetry.io/otel/trace"
 )
 
@@ -25,9 +27,6 @@ var (
 	// Global Tracer instance.
 	Tracer apitrace.Tracer
 
-	// The active tracing configuration, if Enabled is true.
-	config tracingConfig
-
 	initOnce sync.Once
 )
 
@@ -76,6 +75,17 @@ func getServiceName() string {
 	return filepath.Base(os.Args[0])
 }
 
+func defaultResource() *resource.Resource {
+	r, _ := resource.Merge(
+		resource.Default(),
+		resource.NewWithAttributes(
+			semconv.SchemaURL,
+			semconv.ServiceNameKey.String(getServiceName()),
+		),
+	)
+	return r
+}
+
 // Initialize tracing. Tracing will be enabled if the system-wide
 // tracing configuration file is present and valid. Explicitly set
 // TRACING_ENABLE=0 in the environment to disable tracing.
@@ -118,6 +128,7 @@ func initTracing(serviceName string) {
 
 		tp := trace.NewTracerProvider(
 			trace.WithSampler(sampler),
+			trace.WithResource(defaultResource()),
 			trace.WithBatcher(ze),
 		)