Set tracestate on trace initiated by gloo from an incoming/transformed header

[huzlak]

Gloo Edge Product

Enterprise

Gloo Edge Version

v1.16.7

Is your feature request related to a problem? Please describe.

I want to set tracestate header value based on value of a header created by transformation when trace is initiated by gateway-proxy. Currently envoy only sets empty tracestate when it initiates the trace.

Describe the solution you'd like

An option in tracing provider configuration that would allow that, e.g.:

    tracing:
      openTelemetryConfig:
        tracestateFromHeader: $headerName
        collectorUpstreamRef:
          namespace: "gloo-system"
          name: "opentelemetry-collector"

Describe alternatives you've considered

Using baggage to propagate the header, but it's currently not propagated by upstream services which makes it a non-viable solution. Using a transformation to set the header doesn't work as it's overridden by the tracer.

Additional Context

No such option is currently available in upstream envoy opentelemetry tracer.