Add span events when removing reserved labels

Signed-off-by: Yuchen Cheng <rudeigerc@gmail.com>

pkg/strategy/controller.go

@@ -79,14 +79,20 @@ func normalize(ctx context.Context, jaeger *v1.Jaeger) {
 	}
 
 	// remove reserved labels
-	delete(jaeger.Spec.JaegerCommonSpec.Labels, "app.kubernetes.io/instance")
-	delete(jaeger.Spec.JaegerCommonSpec.Labels, "app.kubernetes.io/managed-by")
-
-	delete(jaeger.Spec.AllInOne.JaegerCommonSpec.Labels, "app.kubernetes.io/instance")
-	delete(jaeger.Spec.AllInOne.JaegerCommonSpec.Labels, "app.kubernetes.io/managed-by")
-
-	delete(jaeger.Spec.Query.JaegerCommonSpec.Labels, "app.kubernetes.io/instance")
-	delete(jaeger.Spec.Query.JaegerCommonSpec.Labels, "app.kubernetes.io/managed-by")
+	for _, labels := range []map[string]string{
+		jaeger.Spec.JaegerCommonSpec.Labels,
+		jaeger.Spec.AllInOne.JaegerCommonSpec.Labels,
+		jaeger.Spec.Query.JaegerCommonSpec.Labels,
+	} {
+		if _, ok := labels["app.kubernetes.io/instance"]; ok {
+			span.AddEvent(fmt.Sprintf("the reserved label 'app.kubernetes.io/instance' is overwritten, falling back to %s", jaeger.Name))
+			delete(labels, "app.kubernetes.io/instance")
+		}
+		if _, ok := labels["app.kubernetes.io/managed-by"]; ok {
+			span.AddEvent("the reserved label 'app.kubernetes.io/managed-by' is overwritten, falling back to jaeger-operator")
+			delete(labels, "app.kubernetes.io/managed-by")
+		}
+	}
 
 	// normalize the deployment strategy
 	if jaeger.Spec.Strategy != v1.DeploymentStrategyProduction && jaeger.Spec.Strategy != v1.DeploymentStrategyStreaming {