spanId = mock(SpanId.class);
when(spanId.getParentSpanId()).thenReturn(null);
when(spanId.getSpanId()).thenReturn(SPAN_ID);
when(spanId.getTraceId()).thenReturn(TRACE_ID);
responseProvider = new DefaultHttpResponseProvider(true);
mockServer = new MockHttpServer(PORT, responseProvider);
mockServer.start();
}