public void RootContextOpenTracingSenderTest() { var root = new RootContext(System, new MessageHeader(), OpenTracingExtensions.OpenTracingSenderMiddleware(_tracer)) .WithOpenTracing(tracer: _tracer); var messages = new List <object>(); var actorProps = Props .FromFunc(ctx => { messages.Add(ctx.Message); return(Actor.Done); }) .WithMailbox(() => new TestMailbox()) ; var actor = System.Root.Spawn(actorProps); root.Send(actor, "test_message"); Assert.Equal(2, messages.Count); // Started & "test_message" _tracer.Received(1).BuildSpan("Send String"); _tracer.ClearReceivedCalls(); root.Request(actor, "test_message_2"); Assert.Equal(3, messages.Count); // Started & "test_message" & "test_message_2" _tracer.Received(1).BuildSpan("Request String"); }