qemu command does not start the qemu exporter in v0.5.0 (regression)

[TheElectronWill]

Bug description

When the qemu exporter is enabled via the command line, it is not recognized. That is, scaphandre qemu says scaphandre: Couldn't determine which exporter to run. and stops. Other exporters like stdout work.

To Reproduce

With Scaphandre 0.5.0, I did:

carbo build
./target/debug/scaphandre qemu

and got the following error:

scaphandre: Couldn't determine which exporter to run.

I've also tried with the docker image hubblo/scaphandre:0.5.0 and hubblo/scaphandre:latest, same result.

Expected behavior

The qemu command should enable the qemu exporter, like it did before.

I've tested with previous versions (0.4.1 and 0.4.0), and it works, since I get:

> scaphandre qemu
Scaphandre qemu exporter
Sending ⚡ metrics

Environment

• Ubuntu 22.04.1
• linux 6.1.0-1004-oem

[bpetit]

Thanks for this bug report ! I add it to next batch.

[TheElectronWill]

It seems that the problem is that the qemu feature is disabled, because warpten is enabled. I wonder if there's a reason that the two are exclusive?
e.g. in lib.rs, I've found

#[cfg(all(target_os = "linux", not(feature = "warpten")))]
use exporters::qemu::QemuExporter;

edit: I think I've got an idea for a nice refactoring of the initialization of the exporters, that will fix the bug and remove many duplicate code. I'll try it.

[bpetit]

iirc it was mainly because the warpten exporter still needs to be rewritten to use MetricGenerator as the other exporters do.

Do you already have a PR somewhere about this or should I open one to fix the exporter, then remove this compilation condition ?

[TheElectronWill]

I have a refactoring ready but I cannot turn it into a PR today... It simplifies how exporters are started and how args are handled (by taking advantage of the features of clap 4 - it's much more than a version bump), but I have not rewritten the warpten exporter yet.
Thus, if you already have a fix for the warpten exporter, go ahead! I'll update my changes and come back :)

[bpetit]

should be better in dev now. I'll try to review your refacto PR this week