Failed to get objective: ratio error metric is not a VectorSelector

[harleyharl]

Hello,
I'm trying to use Pyrra to create SLOs for some web vitals I'm trying to track in Grafana.

This is one of my definitions (most of them look similar to this):

apiVersion: pyrra.dev/v1alpha1
kind: ServiceLevelObjective
metadata:
  name: my-site-web-vitals-lcp
  namespace: monitoring
  labels:
    prometheus: k8s
    role: alert-rules
    pyrra.dev/team: webservices
    pyrra.dev/ns: my-site
    pyrra.dev/service: WebVitals
    pyrra.dev/tier: "2"
spec:
  target: "95"
  window: 4w
  description: Largest Contentful Paint should be under 2.5s
  indicator:
    ratio:
      errors:
        metric: web_vitals_lcp{job="mysite.com"} > 2500
      total:
        metric: web_vitals_lcp{job="mysite.com"}

And the error I'm seeing in the pyrra logs

2025-01-21T12:25:18+13:00 2025-01-20T23:25:18.578176201Z stderr F 2025-01-20T23:25:18Z ERROR Reconciler error {"controller": "servicelevelobjective", "controllerGroup": "pyrra.dev", "controllerKind": "ServiceLevelObjective", "ServiceLevelObjective": {"name":"mysite-web-vitals-lcp","namespace":"monitoring"}, "namespace": "monitoring", "name": "mysite-web-vitals-lcp", "reconcileID": "1a8605c4-cbf8-46e7-8b5f-db83ee655c55", "error": "failed to get objective: ratio error metric is not a VectorSelector"}

I realise my metrics are incorrect but I don't know how to properly structure this to make it correct.

According to this:
https://github.com/pyrra-dev/pyrra/blob/932af2bb679e332520deeb5cf33b021942a0834b/examples/openshift/manifests/setup/pyrra-slo-CustomResourceDefinition.yaml

The value for metric is only required to be a string so I'm unsure what is acceptable here?