Add file count metric to filestats receiver

[cxhiggins]

Component(s)

receiver/filestats

Is your feature request related to a problem? Please describe.

I use OpenTelemetry in a deployment which saves all coredumps to a specific folder, and want to export a metric describing the number of cores dumped. This would allow us to enable alerting when processes crash.

Describe the solution you'd like

Ideally the filestats receiver would implement a file.count metric, or something similar, which tracks the number of files which match the specified include parameter.

Unit	Metric Type	Value Type
1	Gauge	Int

Describe alternatives you've considered

I tried using hostmetricsreceiver with a root_path set to our coredump directory, but unfortunately all instances of this receiver must share the same root_path and our other use of the receiver took priority.

Additional context

No response

[github-actions]

Pinging code owners:

• receiver/filestats: @atoulme

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[atoulme]

That's a cool enhancement. Would you like to contribute it?

[github-actions]

This issue has been inactive for 60 days. It will be closed in 60 days if there is no activity. To ping code owners by adding a component label, see Adding Labels via Comments, or if you are unsure of which component this issue relates to, please ping @open-telemetry/collector-contrib-triagers. If this issue is still relevant, please ping the code owners or leave a comment explaining why it is still relevant. Otherwise, please close it.

Pinging code owners:

• receiver/filestats: @atoulme

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[atoulme]

Rethinking this - you can get this information by counting the number of MTS coming from the receiver. I think that gets you what you need. The hostmetrics receiver is also no longer setting env vars, so you can use multiple receivers with different root paths. With that, I think I'll close this issue.

[stef-philipsen-tfs]

Is it possible to re-open this issue? I think this feature would still be useful.

I want to monitor the amount of files that are currently in a directory.

I'm currently using the Datadog agent for this, which is reporting the number of files in the configured folder. This is reported as one metric/one value.

If I would report it via OpenTelemetry in the way described above, this would mean that I would get as many metrics as there are files, which could get expensive depending on the number of files in the directory.

The low cardinality version of the metric would suffice in my use case, since I don't need to know which files are in the directory.

[atoulme]

OK that’s a valid use. Reopening