public static Message<?> addSpanHeaders(TraceKeys traceKeys, Message<?> message, Span span) {
if (span == null) {
if (!message.getHeaders().containsKey(Span.NOT_SAMPLED_NAME)) {
return MessageBuilder.fromMessage(message).setHeader(Span.NOT_SAMPLED_NAME, "").build();
}
return message;
}
Map<String, String> headers = new HashMap<>();
addHeader(headers, Span.TRACE_ID_NAME, Span.toHex(span.getTraceId()));
addHeader(headers, Span.SPAN_ID_NAME, Span.toHex(span.getSpanId()));
if (span.isExportable()) {
addAnnotations(traceKeys, message, span);
Long parentId = getFirst(span.getParents());
if (parentId != null) {
addHeader(headers, Span.PARENT_ID_NAME, Span.toHex(parentId));
}
addHeader(headers, Span.SPAN_NAME_NAME, span.getName());
addHeader(headers, Span.PROCESS_ID_NAME, span.getProcessId());
} else {
addHeader(headers, Span.NOT_SAMPLED_NAME, "");
}
return MessageBuilder.fromMessage(message).copyHeaders(headers).build();
}
@Test
public void when_not_sampling_header_present_span_is_not_exportable() throws Exception {
Long expectedTraceId = new Random().nextLong();
MvcResult mvcResult = whenSentPingWithTraceIdAndNotSampling(expectedTraceId);
then(tracingHeaderFrom(mvcResult)).isEqualTo(expectedTraceId);
then(span.isExportable()).isFalse();
}
@Test
public void when_always_sampler_is_used_span_is_exportable() throws Exception {
Long expectedTraceId = new Random().nextLong();
MvcResult mvcResult = whenSentPingWithTraceId(expectedTraceId);
then(tracingHeaderFrom(mvcResult)).isEqualTo(expectedTraceId);
then(span.isExportable());
}