Add Warning for wrongly named files

[marcusboden]

Enhancement Proposal

It would be nice to have a warning in the logs for files that don't follow the (undocumented?) naming scheme of having e.g. a .rules or .rule suffix. At the moment, if you name your rules file my-alert.yaml it get's silently ignored.

[sed-i]

You are correct, it is currently documented only as the module-level docstring of the charmlib:

cos-configuration-k8s-operator/lib/charms/loki_k8s/v0/loki_push_api.py

Line 372 in 1fe7fe1

in YAML format. The file name must have the `.rule` extension.

Iirc, the original reasoning was that there could be *.md files or other files accompanying the rule files.

How about a WARNING if no files are there,

cos-configuration-k8s-operator/lib/charms/loki_k8s/v0/loki_push_api.py

Line 870 in 1fe7fe1

for file_path in self._multi_suffix_glob(dir_path, [".rule", ".rules"], recursive):

An easy way to do it is to use the for-else. Would you like to contribute it?

[marcusboden]

Wouldn't the warning then be triggered each time if you don't have any loki rules defined in your git (which is the case for most of our deployments)? That's a bit verbose and maybe not what we want.

I thought about adding a small info or debug log to:
https://github.com/canonical/loki-k8s-operator/blob/main/lib/charms/loki_k8s/v1/loki_push_api.py#L926-L927

Just compare the two lists and print the difference to see what was filtered out.

[sed-i]

Yep that could work!

[marcusboden]

Would you like to contribute it?

Since you asked so nicely, I sent you a PR ;)