OpenTelemetry support

[gloshkajian]

Currently, there exists an OpenTelemetry maintained instrumentor for httpx.

https://github.com/open-telemetry/opentelemetry-python-contrib/tree/main/instrumentation/opentelemetry-instrumentation-httpx

Teams that migrate away from httpx to httpx2, but are also using this instrumentor, would find themselves losing httpx telemetry.

In today's Python SIG meeting, we discussed open-telemetry/opentelemetry-python-contrib#4635, and the follow-up was to check in on httpx2's appetite for supporting opentelemetry natively. Notes here: https://docs.google.com/document/d/18w8zOBm_mbety0OqlPwxc7dvnfu641EgmrO4AdJef0U/edit?tab=t.0 . Based on what the maintainers suggest, OpenTelemetry would decide whether or not to implement support for httpx2 on their side.

So in this discussion I'd like to understand that better to bring back to to the OTEL Python SIG.

[Kludex]

I'll publish opentelemetry-instrumentation-httpx2 at some point this weekend/week while I figure it out how we are going to do this natively in httpx2.

If I don't find a way to do it in a cute way, at least we can just have the monkeypatched way anyway.

[gloshkajian]

@Kludex thank you!

This may or may not change things, but at least in the SIG, there was an expressed preference for having the httpx instrumentor handle httpx2 as well, instead of a separate instrumentor. If we don't think that's appropriate, that's fine. But it's worth flagging as a question they might have for a PR to opentelemetry-python-contrib

[Kludex]

I'm fine with that. That's easy for me, and for consumers.

[Kludex]

It seems we are going to have httpx2 instrumentation support under opentelemetry-instrumentation-httpx: https://cloud-native.slack.com/archives/C01PD4HUVBL/p1780674709507989