[FEATURE] Prometheus Endpoint for Template Rendering Times

[MillsyBot]

Hey Criteo!

This is an amazing product, we have been using it for over a year to render large and extra-large pools. The one thing that we are missing from this product is away to view statistics on each template including: reloads, render times, failures (if any, we generally code around missing values, but being able to notify prometheus would be great).

Again, this awesome, hope this is a reasonable ask! Have a great holiday!

[pierresouchay]

Hello @MillsyBot ,

The tool is actually able to expose prometheus metrics, not with http natively, but by exposing a file compatible with prometheus metrics. Such file can then be exposed using your favorite HTTP server.
Here is an example in samples on how doing that :
https://github.com/criteo/consul-templaterb/blob/master/samples/metrics.erb

Did you already had a look?

It already exposes quite a few technical information about consul-templaterb (such as bytes, errors and so on...)

If you require more info than what is already exposed, maybe it could be possible to add more information if you come with a specific list.

Note: there are many other examples of various prometheus exports (RTT between agent nodes, DCs...) in https://github.com/criteo/consul-templaterb/blob/master/samples/

Regards

[MillsyBot]

This is great. THanks!