add prometheus_flask_exporter

[charlienegri]

Summary: extract metrics via prometheus_flask_exporter

Related issue:

220

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[charlienegri]

local test seems to expose the metrics at least

[charlienegri]

@magnarem this should not conflict with the catalog-rebuilder-flask metrics endpoint right? because dmci has its own container port (8000) as far as I understand, and that's where these /metrics will end up

[magnarem]

I think it should be no problem. The k8s nginx in front of dmci, should handle request dmci.s-enda.k8s.met.no/metrics og catalog-rebuilder.s-enda.k8s.met.no/metrics to the right ones...If unsure, maybe the k8s people can give a better answer.

[charlienegri]

the path label can be used to discriminate the endpoint

[charlienegri]

I think we'll need to add annotations to the base/dmci/statefulset.yaml in the tjeneste repo for the metrics to be actually scraped, as there are for catalog-rebuilder-flask, basically identical lines but just with a changed port, should be 8000 if I read the code right

[magnarem]

Yes, for promethues to see the metrics, you will have to add the right anotations.

The dmci pod did not start properly.

Here is the error from the dmci startup log:

ModuleNotFoundError: No module named 'prometheus_flask_exporter'

You will need to add the prometheus_flask_exporter dependency to the setup.cfg for the installer to install this module.

Add it under: install_requires =

[charlienegri]

🙃 I added it to the requirements file and forgot about that ... I will open a PR to fix this

[charlienegri]

patch https://github.com/metno/discovery-metadata-catalog-ingestor/pull/234