feat(init): bundle Prometheus + fix OpenCost RBAC (follow-up to #21)#22
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OpenCost watches PodDisruptionBudgets; without the rule its reflector spams "poddisruptionbudgets.policy is forbidden". Caught on a real cluster.
…ined OpenCost has a hard Prometheus dependency; on a cluster without Prometheus it crash-loops (FTL) no matter the endpoint. Make init deploy the whole Tier-2 stack so cost works in one command, no prerequisites — caught on a real cluster running SigNoz (no Prometheus). - Embed a minimal Prometheus manifest (monitoring namespace, scrapes kubelet/cAdvisor) at prometheus-server.monitoring.svc:80 — which is both OpenCost's default endpoint AND a kubetidy auto-detect candidate, so scan Tier-1 and OpenCost Tier-2 both find it with zero config. - `init --with-opencost` now also deploys the bundled Prometheus unless --prometheus-url points at an existing one (then the bundle is skipped). - `init --with-prometheus` deploys just Prometheus (unlocks Tier 1) on its own. - `uninstall --with-prometheus` removes it — but never the shared `monitoring` namespace (deleteManifestSkipNamespaces), so a user's other tooling is safe. - --print includes whatever --with-* flags select. - Docs: README setup + Tier 2, ROADMAP, CHANGELOG.
… proxy scan runs on the user's machine, but auto-detection returned an in-cluster Service DNS name (*.svc) that only resolves inside the cluster. Every query failed with "no such host" and the scan silently reported a misleading 100/100 $0 (zero usage mistaken for zero waste) — hit on a real cluster. - Reach an auto-detected Prometheus/OpenCost through the Kubernetes API server proxy (/api/v1/namespaces/<ns>/services/<svc>:<port>/proxy), reusing the kubeconfig's API server address + credentials. Works wherever kubectl works, no port-forward. - Validate reachability (a trivial `up` query / live allocation fetch) before committing to Tier 1 / Tier 2; an unreachable endpoint falls back to the operator / metrics-server / derived pricing with a clear note. - Expose kube.Clients.RESTConfig; add DetectPrometheusEndpoint / DetectOpenCostEndpoint (+ struct), NewPrometheusProviderViaAPIProxy, NewOpenCostProviderViaAPIProxy, and usage.Reachable. Auto-detect now sits behind provider seams (prometheusAutoProvider / openCostAutoProvider). - An explicit --prometheus-url / --opencost-url is still used directly.
…ntext Workload names with dots (CSI drivers like rbd.csi.ceph.com-nodeplugin) or other regex metacharacters produced `unknown escape sequence U+002E '.'`: regexp.QuoteMeta yields `\.`, which is an invalid escape inside a PromQL double-quoted string, so those workloads were skipped. Double the backslashes when embedding the pod regex. Caught on a real cluster.
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Why a follow-up
PR #21 was merged right after its first commit, before two further commits landed on the branch. Both were found while testing #21 on a real cluster (running SigNoz, no Prometheus). This PR brings them into
main.1. Fix: OpenCost RBAC missing
policy/poddisruptionbudgetsOpenCost watches PodDisruptionBudgets; without the rule its reflector spammed
poddisruptionbudgets.policy is forbidden. Adds thepolicygroup to the embedded ClusterRole.2. Feature: bundle Prometheus so
init --with-opencostis self-containedOpenCost has a hard Prometheus dependency — on a cluster without one it crash-loops (
FTL Failed to create Prometheus data source ... no such host), no matter the endpoint. That's exactly what happened in testing. Soinitnow deploys the whole Tier-2 stack:internal/installer/assets/prometheus.yaml) — monitoring namespace, scrapes kubelet/cAdvisor, atprometheus-server.monitoring.svc:80. That address is both OpenCost's default endpoint and a kubetidy auto-detect candidate, so scan Tier-1 and OpenCost Tier-2 both find it with zero config.init --with-opencostnow also deploys the bundled Prometheus unless--prometheus-urlpoints at an existing one (then the bundle is skipped).init --with-prometheusdeploys just Prometheus (unlocks Tier-1 history) on its own.uninstall --with-prometheusremoves it — but never the sharedmonitoringnamespace (deleteManifestSkipNamespaces), so a user's other tooling is safe.--printincludes whatever--with-*flags select.The bundled Prometheus is deliberately minimal (single replica, ephemeral storage, 15-day window) — great for getting cost working immediately; run your own and pass
--prometheus-urlfor durable metrics.Tests
internal/installer/opencost_test.go: Prometheus manifest decode (7 kinds) + correct default endpoint;Uninstall --with-prometheuslogs removal and keeps the namespace;deleteManifestSkipNamespacespreserves a seededmonitoringnamespace.internal/cli/init_test.go:includePrometheus()truth table;--printbundles Prometheus with--with-opencost/--with-prometheus, omits the bundle when--prometheus-urlis given.Full gate green: build, vet, gofmt,
go test ./..., golangci-lint (0 issues).🤖 Generated with Claude Code