Brief introduction to creating a helm chart for deploying SLOs in monitoring namespace.

Confluence doc on components: https://autonomic-ai.atlassian.net/wiki/spaces/OPLAT/pages/2753036316/SLO+Framework

This chart was created by running helm create slo-demo Helm will scaffold a chart for you. I removed the auto generated templates folder because we will be using the slo chart created by observability team and hosted in au helm repository. Speaking of which, that is configured in the requirements.yaml.

dependencies:
  - name: slo
    version: "*"
    repository: "@au"
    alias: slo-demo

Here we are specifying that this chart is dependent on the slo chart. Therefore we must run helm dep up || helm dependency update to fetch the dependent chart. More info here

helm dep up
helm template slo-demo  . --set environment=dev > my-psl.yaml

This will template out a psl crd which defines the slo spec for the sloth controller to convert the PSL into Prometheus Rules CRDS.

kubectx gke-d-tmc-01
kubens monitoring
kubectl apply -f my-psl.yaml

Switch to gcp-dev cluster and monitoring namespace. Using kubectl we will deploy our psl.

kubectl get psl | grep slo-demo
kubectl get prometheusrule | grep slo-demo

Sloth controller https://sloth.dev/examples/kubernetes/getting-started/ will have converted the PSL into a PrometheusRules CRD

This Prometheus Rules CRD gets converted by prometheus-rules-controller side car running on prometheus pod, into a prometheus recording rule in the etc/config/controller-rules directory. Prometheus will reload its config and update recording rules.

kubectl port-forward <prometheus-server-#######-#####> 9090

browse to http://localhost:9090/rules and your recording rule should be defined.

kubectl delete psl slo-demo

prometheus rules CRD will be deleted and will be ereased from prometheus rules on prometheus-server.