Metric collection fails on current versions of prometheus_client

[jralbert]

The Docker container ships with prometheus_client 0.13, which appears to be less stringent about its inputs; however, installing the exporter alongside a current 0.4.2 version of prometheus results in many metrics not being returned at all.

By adding a try-except block around lines lines 141-151 in hypervisor_stats.py (https://github.com/att-comdev/prometheus-openstack-exporter/blob/master/exporter/hypervisor_stats.py#L141-L151), I was able to identify that prometheus_client is throwing a Duplicated timeseries in CollectorRegistry exception when assembling the metrics for delivery.

I suspect that the older version of prometheus_client was simply silently overwriting duplicate timeseries. I believe the same issue may affect all of the collector modules. Exception handling should be added around calls to the prometheus_client methods, and input should be sanitized ahead of those calls to ensure no duplicate timeseries are propagated. I'd be happy to help develop a PR to address some of this, if I can get some guidance from the project maintainers on how they'd like to see that implemented.

[berendt]

@jralbert According to the requirements.txt version 0.2.0 is required.

[jralbert]

It certainly is; that version surfaces the same problematic behavior.

…

________________________________ From: Christian Berendt <[email protected]> Sent: Wednesday, October 17, 2018 11:28 AM To: att-comdev/prometheus-openstack-exporter Cc: Jeff Albert; Mention Subject: Re: [att-comdev/prometheus-openstack-exporter] Metric collection fails on current versions of prometheus_client (#6) @jralbert<https://github.com/jralbert> According to the requirements.txt version 0.2.0 is required. - You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub<#6 (comment)>, or mute the thread<https://github.com/notifications/unsubscribe-auth/ATtuT4vuEHxF5Wd9e2uXBcmtlnYkNRF6ks5ul3a5gaJpZM4Xewuz>.

[Molnigt]

Does anyone have a solution for this? It is still broken with the newer versions.