fix(otel): Don't require entrypoint config to initialize OTel

[hairyhenderson]

Description

Changes behaviour to always call otelService.Init, to avoid requiring setting the openTelemetryOtlpEndpoint config element.

If the OTel SDK is not explicitly disabled and no OTel endpoint is listening, the OTel SDK will complain in the logs. Since I don't want to unnecessarily spam logs, I'm adding support for the OTEL_LOG_LEVEL variable, but defaulting to debug rather than the spec's info for somewhat more sane logs.

Notes: I've not done it here, but I think deprecating openTelemetryOtlpEndpoint in the future is probably a good idea, in preference for otel.exporter.otlp.endpoint. I've also noticed that the otel config section is undocumented - I may have a look at that in a separate PR.

Closes issue(s)

Fixes #2578

Checklist

• I have tested this code
• I have added unit test to cover this code
• I have updated the documentation (README.md and /website/docs)
• I have followed the contributing guide

[netlify]

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[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 5 lines in your changes missing coverage. Please review.

Project coverage is 85.09%. Comparing base (3bfac24) to head (6f03a74).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/relayproxy/api/server.go	40.00%	2 Missing and 1 partial ⚠️
cmd/relayproxy/api/opentelemetry/otel.go	60.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2579      +/-   ##
==========================================
- Coverage   85.11%   85.09%   -0.02%     
==========================================
  Files         101      101              
  Lines        4582     4583       +1     
==========================================
  Hits         3900     3900              
  Misses        544      544              
- Partials      138      139       +1     

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[thomaspoignant]

@hairyhenderson I have tested this new version and my main concern is that we are still trying to call the OTLP when nothing is configured.

We have this log for every query:

{"level":"debug","ts":1730195483.37956,"caller":"opentelemetry/otel.go:93","msg":"OTel error","error":"traces export: Post \"https://localhost:4318/v1/traces\": dial tcp [::1]:4318: connect: connection refused"}

Maybe we should set the noop.NewTracerProvider() when we have no OTLP endpoint configured.

[hairyhenderson]

We have this log for every query:

yeah, that's why I set it to log at debug level...

Maybe we should set the noop.NewTracerProvider() when we have no OTLP endpoint configured.

Yeah, the issue is that if there's no exporter, defaults will be used (OTLP over http/protobuf on https://localhost:4318). I had thought that perhaps some users would want this.

Realistically though, I think I'm the only user of GOFF that needs the OTel support so far, so requiring the endpoint to be set is probably fine.

I'll update this to check openTelemetryOtlpEndpoint or otel.exporter.otlp.endpoint for now.

[hairyhenderson]

@thomaspoignant I've simplified things - PTAL 🙂

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[thomaspoignant]

Looks really good now 👍