06 — Monitoring (Prometheus + VictoriaMetrics, Service + Pod targets)

Three workloads exercising the monitoring matrix:

api — Prometheus ServiceMonitor (CRD discovery + service target).
worker — Prometheus PodMonitor (CRD discovery + pod target). No Service.
legacy — annotations-mode (prometheus.io/scrape etc.) for clusters that haven’t installed Prometheus Operator CRDs.

Plus chart-level exposeService.enabled: true so metrics ports are auto-emitted on Services that don’t declare one.

What this shows

integrations.monitoring.defaults sets Prometheus + CRD + service as the cluster default.
Per-workload metrics.* overrides every axis individually:
- api accepts the defaults (single value: metrics.enabled: true).
- worker switches type: pod to emit a PodMonitor instead.
- legacy switches discovery: annotations to skip the CRD entirely.
Auto-exposed metrics port on api (exposeService.enabled: true with no explicit service.ports.metrics).
Metrics-only Service for worker because its service.enabled: false — the chart still emits a <release>-worker-metrics Service so the PodMonitor’s port name resolves cleanly.
A victoriametrics-flavoured workload showing the per-workload provider override.

Changed	What
`integrations.monitoring.defaults`	Set chart-level monitoring defaults explicitly.
Three workloads	One per discovery/target combination.
`metrics.exposeService.enabled`	Enabled chart-wide so the metrics port lands automatically where applicable.
`metrics.type: pod` on `worker`	PodMonitor instead of ServiceMonitor.
`metrics.discovery: annotations` on `legacy`	Bare Prometheus annotations on the Service.
`metrics.provider: victoriametrics` on `vm-flavoured`	Per-workload provider override (emits `VMServiceScrape` instead of `ServiceMonitor`).

File	Purpose
`values.yaml`	Chart values.
`argocd/application.yaml`	Argo CD `Application`, single source.
`argocd/application-multisource.yaml`	Argo CD `Application` with `spec.sources[]`.
`flux/ocirepository.yaml`	Flux `OCIRepository`.
`flux/helmrelease.yaml`	Flux `HelmRelease`.
`helm/install.sh`	Plain `helm upgrade --install`.

bash helm/install.sh
kubectl apply -f argocd/application.yaml -n argocd
kubectl apply -f flux/

Prometheus Operator CRDs (monitoring.coreos.com) installed for ServiceMonitor / PodMonitor to materialise.
VictoriaMetrics Operator CRDs (operator.victoriametrics.com) installed for the vm-flavoured workload’s VMServiceScrape. Remove the vm-flavoured workload if VM Operator isn’t present.
Prometheus / vmagent configured to discover the right CRDs / pick up annotations.