opentelemtry-flask health check path already excluded but sill creating child spans

[yankeguo]

I'm using opentelemetry instrumentations for flask, sqlalchemy and redis.

I'm doing sqlalchemy and redis connection checks (by sql select 1 and redis ping) in endpoint /healthz.

I've excluded url /healthz from flask instrumentation, and tracing records of /healthz did disappeared.

But the tracing events of database select 1 and redis ping are still emitting as dedicated spans, showing in jaeger query.

Am I doing it wrong?

[srikanthccv]

Excluding certain routes from being traced in flask app doesn't automatically make the other instrumentations also not produce spans under that endpoint. At least that's how it works as of today. May be there is an expectation mismatch here. Or your assumption should be the actual behaviour. cc @open-telemetry/python-approvers

[yankeguo]

Thanks for replying.

Is there any way to suppress child span from emitting manually, something like:

tracer = trace.get_tracer(__name__)
with tracer.start_noop_span():
    do_something()

[srikanthccv]

Unfortunately you can't do that. There is no such api and all the calls are no-op until you register the tracer provides. Once you set it there is no way to undo that currently.

[owais]

I think instead of not generating spans, we should use suppression in these cases. It is hard to imagine a use case where someone would not want to a root server span for a specific path but still want to generate child spans and if such a use case did exist, sampling would probably be a better solution for that.