[SOLVED] Tracing per endpoint using Spring Boot and micrometer

Tracing per endpoint using Spring Boot and micrometer

I have a REST API which exposes two endpoints.

Endpoint 1 is a low traffic, but mission critical. We need to trace everything from the controller layer all the way to the repository.
Endpoint 2 has a very high traffic volume, but it is not super important in terms of observability requirements. It needs to work of course, but no need to see tracing here.

@RestController
class ReportController {

  private static final Logger LOGGER = LoggerFactory.getLogger(ReportController.class);

  @Autowired
  ReportService reportService;

  @GetMapping("/businessCriticalFLow")
  String businessCriticalFLow(@RequestBody String string) {
    LOGGER.info("would like to see traces like this INFO [app,bbe3aea006077640b66d40f3e62f04b9,93b7a150b7e293ef]");
    Report report = reportService.getReport(string); //will see traces from the repository as well
    return ...;
  }

  @GetMapping("/notSoImportant")
  String notSoImportant(@RequestParam(value = "id", required = true) int id) {
      return ...;
  }

}

We have the current solutions:

disable tracing entirely (removing micrometer, or setting false to the micrometer property in application properties)

Result -> We lose everything, no observability on the endpoint 1 (important flow)
enable tracing for everything (default behavior when bringing micrometer, actuator and co)

Result -> We waste money sending traces we will not use for flow 2 just to see traces of flow 1
refactor and break the app into two apps, one endpoint each, one that has tracing enabled, and one that does not.

Is there a way we can achieve tracing per-flow, per endpoint using micrometer and Spring Boot?

Solution