Two new value maps under `prometheusRules`:
- `alertExprOverrides` — alertName -> custom Prometheus expression
that replaces the default `expr:`. Closes#253: multi-cluster setups
can inject `max by (cluster, …)` aggregations or label filters
without having to disableBuiltinAlertGroup and reconstruct everything.
- `alertForOverrides` — alertName -> `for:` duration that replaces
the default. Schema-validated against Prometheus's duration syntax.
Both maps key on bare alert names (no `rulePrefix`). Overrides are
taken whole — no merge with the default. Single-line and multi-line
strings both render correctly: the template now emits each `expr:`
via `| quote` which wraps in a YAML double-quoted scalar (newlines
serialise to \n; Prometheus parses the resulting string identically
to the multi-line form).
Test ratchets added alongside:
- test/schema/valid/prometheusrules-alert-overrides.yaml — valid case
covering both maps, with a multi-line expr to exercise the quoting
path.
- test/schema/invalid/prometheusrules-alertforoverrides-bad-duration
— paired with .expect.txt, ensures the duration regex rejects
natural-language inputs ("30 minutes").
- test/render/prometheusrules-default-alerts.{yaml,expect-pass.txt} —
new ratchet under the existing TestHelmRender machinery (extended
to support "positive substring" checks via .expect-pass.txt). Locks
in the exact 13 alert names the chart ships by default: any rename
or accidental removal breaks the test at PR time.
Docs:
- chart/README.md.gotmpl alert table refreshed — was still on the v3
layout (X509ExporterReadErrors + 3 cert alerts). Now lists all 13.
- values.yaml gets the two new map keys with descriptions and
commented examples.
Thibault VINCENT