Customising the name of the trace being sent from Faro?

[adamk9k]

Hello,

we're using OTEL with a Ruby backend already and have everything set up with Grafana. I'm currently trying to add web tracing with Faro as well and it works nicely after some configuration, traces are linked from the backend with the traces from the FE.

My only question is if it's possible to customise the name of the trace that is being generated by Faro? I couldn't find the place where it's being generated, the payload looks like this for HTTP requests

[{"traceId":"cef17151ca220b187248de8b4dcf7aa9","spanId":"535b64ea7153eaf7","name":"HTTP GET","kind":3,"startTimeUnixNano":"1737476136283000000","endTimeUnixNano":"1737476140007000000","attributes":[{"key":"component","value":{"stringValue":"fetch"}},{"key":"http.method","value":{"stringValue":"GET"}}

And in Grafana it shows up like this

Which is really non-descriptive. For instance, Backend traces are customised and look like this for instance:

Thanks in advance

[codecapitano]

Hi @adamk9k

The span naming scheme for HTTP requests is defined by the OTEL spec.

Faro provides an option to inject config options into the underlying otel fetch instrumentation.
Here you can use the applyCustomAttributesOnSpan function to update the span name.

itializeFaro({
    // ...
    instrumentations: [
      // ...

      new TracingInstrumentation({
        instrumentationOptions: {
          fetchInstrumentationOptions: {
            applyCustomAttributesOnSpan: (span) => {
              span.updateName('NEW_SPAN_NAME');
            },
          },
        },
      }),
      // ...
    ],
  });

Cheers,
Marco

[adamk9k]

Amazing, thank you for the quick response!