Verify does not work with OpenMetrics

[xonvanetta]

Wanted to make a PR but it seems like there is no solution near.
Did not find a parser for OpenMetrics so could not create a PR here.

prometheus/client_golang#829

Workaround for now is to skip verify:

modules:
  mimir:
    method: http
    http:
      verify: false
      port: 8080

Error code from exporter_exporter is:
ERRO[0003] Verification for module 'mimir' failed: Failed to decode metrics from proxied server: text format parsing error in line 89: unknown metric type "unknown"

[tcolgate]

Since exemplars require openmetrics, this is a bigger deal than it sounds. I've a feeling that there is a parser in the prom common libraries somewhere. I'll take a look.

[xonvanetta]

I have found this one
https://github.com/prometheus/prometheus/blob/867d3bd78f514ffffcfd5da751cb2bd84c6aba72/model/textparse/openmetricsparse.go

But like you said its pretty big and what I found it still experimental