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Aleksei Sviridkin
785cbc391b
## What this PR does Fixes #4060. `flux-plunger` recovers a HelmRelease stuck with `has no deployed releases` by briefly suspending it, deleting the stale Helm storage Secret, recording a processed-version annotation, and unsuspending. helm-controller v1.5.x skips the Helm uninstall and drops its finalizer when it handles a delete on a suspended HelmRelease, and it wakes on the same delete event flux-plunger does, so a delete arriving inside that window orphaned every resource the release owns (for a VMDisk: DataVolume, PVCs, the CDI importer pod, RBAC, WorkloadMonitor and the storage Secret itself). Lifting the suspension on the delete event cannot win that race reliably. The bug is not specific to VMDisk. The change makes such a delete reach the uninstall: - **An uninstall fence.** The suspension is applied together with a flux-plunger finalizer, `flux-plunger.cozystack.io/uninstall-fence`, in one server-side apply, so flux-plunger never holds a suspension without it. If a delete arrives while the release is suspended, the fence keeps the object whether helm-controller or flux-plunger handles the delete first: flux-plunger lifts its suspension and keeps the fence, helm-controller reconciles the unsuspended generation and runs the uninstall, and flux-plunger removes the fence once helm-controller's finalizer is gone and it has observed that generation. A recovery that completes lifts the suspension and the fence together. A terminating HelmRelease never begins recovery, and termination is re-checked immediately before deleting the storage Secret. - **Only flux-plunger's own suspension is acted on.** Ownership is decided by which field manager owns `spec.suspend` in `metadata.managedFields`: the apiserver transfers the field away the moment an operator (or `cozyhr resume`, or a backup/restore controller) writes a different value to it, so a later suspension is never misread as flux-plunger's. A suspension set through the shared `flux-client-side-apply` manager (platform migrations, the tenant delete hook, an operator's manual `kubectl apply`) is never claimed. A release deleted under another manager's suspension is that manager's decision: flux-plunger does not hold it with the fence, and helm-controller leaves its resources in place, as the migrations that suspend and then delete rely on. - **No suspension taken over in a race.** Acquiring applies without forcing first and, on a conflict, re-fetches and forces only if `spec.suspend` is still `false`: a backup controller owns the field at `false` via a dynamic-client `Update`, which a non-forced apply can never take. Every apply flux-plunger sends, acquiring as well as lifting the suspension or the fence, is preconditioned on the `resourceVersion` and `uid` of the read that decided on it. The `resourceVersion` makes a write landing in between fail the apply instead of being absorbed: acquire then defers rather than adopt or take over a suspension set meanwhile, and lifting the suspension and the fence from a release read as live cannot delete it without an uninstall if helm-controller has handled a delete in the meantime. The `uid` stops an apply to a release that has gone from creating an empty one, since server-side apply creates what does not exist. A conflict is retried through the requeue. The apply carries only `spec.suspend` and the fence, so it cannot leak the required `spec.interval` and conflict on it. - **Fresh reads.** The release, every re-check and the storage Secret list are read from the apiserver (an uncached `APIReader`), not the informer cache. A lagging cache would let the processed-version guard delete the revision below the one just reclaimed, and the ClusterRole grants secrets `get`/`list` but not `watch`, which an informer needs to stay synced; flux-plunger deliberately does not cache Secrets. Every step requeues with backoff on failure. - **Events.** A Warning when flux-plunger holds a suspension it failed to clear, and a Warning when a delete has been held by the fence for more than ten minutes waiting for helm-controller (the held state is re-checked on a timer, not only on helm-controller's next status write). A release deleted under another manager's suspension gets a Normal event when that is a migration's choice, and a Warning when the release carries flux-plunger's processed-version annotation, because then the skipped uninstall is an accident, not a decision. Normal events also mark an externally-owned suspension left alone and a recovery deferred because the release changed between read and write; an external suspension on a release flux-plunger has recovered before is a Warning instead, because it is most likely one an earlier flux-plunger left mid-recovery (see Operating notes). Events from the shutdown drain are written straight to the apiserver, since the manager's recorder stops with the manager. - **The fence is released when flux-plunger goes.** Once its manager has stopped, and with it every reconcile, flux-plunger drains its fences under a deadline inside the pod's termination grace period; a stop that overran its 10s bound is drained too and still reported: a recovery in progress is aborted, the suspension and the fence lifted together for the next flux-plunger to start again, and a release being deleted has flux-plunger's suspension lifted and keeps the fence until helm-controller has run its uninstall. A release helm-controller does not handle in time keeps its fence. The drain lives in the controller, so the envtest suites hold it against a real apiserver's generations and finalizers. A pre-delete hook on the chart is the backstop for what the drain could not finish, so uninstalling the component never leaves a release it cannot finish deleting: it stops flux-plunger, waits out its grace period, then lifts any remaining suspension and fence without waiting again, naming each release it lets go of before helm-controller uninstalled it. It lifts a suspension only where flux-plunger alone holds it, the outcome the controller's own relinquish has, with a JSON patch of `spec.suspend` preconditioned on the `resourceVersion` and `uid` it read; not with `kubectl apply --server-side`, which on a release last written by a client-side `kubectl apply` moves that apply's fields to the applying manager and strips every one the body leaves out. helm-controller runs a pre-delete hook under the release's uninstall timeout, 300s by default and not set by the operator, so the Job's deadline sits under it. A Deployment that cannot be stopped or a listing that never succeeds ends the hook before any fence is touched, and a fence it cannot remove ends it after the sweep; either way it exits non-zero, because a failed pre-delete hook leaves the release untouched and helm-controller retries the uninstall, hook included, whereas exiting 0 would let the component go and strand the fence. A flux-plunger pod still there after its grace period, typically one stuck `Terminating` on a `NotReady` node, is only reported, and the pod wait is cut to what is left of the hook's retry window; because such a pod may still be setting fences, the fences are listed again after the sweep and any found fails the hook. The Job runs once and is kept after success so its report stays readable until its TTL; `helm.sh/hook-output-log-policy` is deliberately not used, because helm-controller never sets Helm's hook output writer and calls a nil one for it (fluxcd/helm-controller#1562). The hook's kubectl image is digest-pinned in the chart values, and its RBAC is only what `kubectl scale`, the listing and the patches issue. The chart's README documents the finalizer and how to clear it by hand. A single writer is kept by leader election, not by the rollout. A second process acting under the same field manager could clear a suspension the first is still recovering, and no Deployment strategy prevents one: the next pod starts as soon as the old one is terminating (Kubernetes v1.35 has no pod-replacement policy for Deployments), and an eviction or a node drain replaces a pod the same way, while the old one stops and drains. The chart now passes `--leader-elect` with a Role on `leases` in the release namespace. The Lease is not given up on stop and outlasts the last renewal, the renew deadline, the manager's bounded stop (10s) and the drain, and only a flux-plunger that led drains at all, so the next one acts only once the old one is done; the price is that a new pod waits for the Lease to run out, a little under two minutes at the default. The timings derive from one value, `shutdownGracePeriodSeconds` (90 by default, refused outside 40 to 140 at render): the pod's termination grace period, the drain deadline (25s less: the manager's 10s stop plus a 15s margin before the kubelet's SIGKILL, both tied to the Go constants by a contract test) and the hook's pod wait. The strategy keeps `maxSurge: 0` and `maxUnavailable: 1` and stays `RollingUpdate` rather than `Recreate` on purpose: the chart shipped without a strategy block, so every existing install's live Deployment carries the apiserver-defaulted `rollingUpdate` object and helm-controller applies server-side, where laying `type: Recreate` over that populated block is rejected on upgrade. ### Operating notes A HelmRelease carries the fence only while flux-plunger is recovering it or waiting for helm-controller to uninstall it. A fenced release whose uninstall keeps failing stays `Terminating` exactly as any HelmRelease does under helm-controller's own finalizer, and raises the Warning above. Stopping flux-plunger drains its fences, and uninstalling it releases whatever the drain left through the pre-delete hook; a fenced release that is deleted while flux-plunger is merely scaled to zero, or killed without a graceful stop, and that helm-controller has not uninstalled, stays `Terminating` until flux-plunger runs again. To release one by hand, after confirming its uninstall has run or is not wanted: ```bash kubectl patch helmrelease NAME --namespace NAMESPACE --type json --patch '[{"op":"test","path":"/metadata/finalizers/INDEX","value":"flux-plunger.cozystack.io/uninstall-fence"},{"op":"remove","path":"/metadata/finalizers/INDEX"}]' ``` where `INDEX` is the position of `flux-plunger.cozystack.io/uninstall-fence` in `metadata.finalizers`; the `test` operation makes the patch fail rather than remove another finalizer if the list has changed. Earlier flux-plunger releases set `spec.suspend` through the shared `flux-client-side-apply` manager, so a suspension one of them left behind cannot be told apart from a migration's or an operator's and is treated as external: it is not cleared automatically. Such a leftover exists only if the old pod stopped in the middle of a recovery, and flux-plunger raises a `SuspensionNotOwned` Warning on it. The chart README carries this section too. To list candidates, suspended releases carrying the flux-plunger annotation whose `spec.suspend` is not owned by flux-plunger's apply: ```bash kubectl get helmreleases.helm.toolkit.fluxcd.io --all-namespaces --output json | jq --raw-output '.items[] | select(.spec.suspend == true) | select(.metadata.annotations["flux-plunger.cozystack.io/last-processed-version"] != null) | select([.metadata.managedFields[]? | select(.manager == "flux-plunger" and .operation == "Apply" and .fieldsV1["f:spec"]["f:suspend"] != null)] | length == 0) | "\(.metadata.namespace)/\(.metadata.name)"' ``` Clearing one is an operator action: confirm nothing else (a migration, a restore) is holding it, then resume it with `flux resume helmrelease NAME --namespace NAMESPACE`. ### Testing The regression the issue asks for is `TestEnvtest_DeleteDuringRecoveryReachesUninstall`: against a real apiserver, a delete lands while flux-plunger holds its recovery suspension, and helm-controller's v1.5.0 delete handling is reproduced step for step (uninstall only when not suspended, finalizer dropped either way, observed generation recorded). It covers both orders, helm-controller handling the delete first and flux-plunger handling it first; without the fence the first order leaves the release gone with no uninstall. The same suite pins the managedFields ownership dynamics a fake client cannot represent: the field transfer, the forced acquire over a dynamic-`Update` owner, the `resourceVersion` precondition rejecting a write that races either apply, the boundary that a `flux-client-side-apply` suspension is never claimed, and interval preservation. The fence mechanics were also checked against a live helm-controller: with another finalizer holding a deleted, suspended release, lifting the suspension made helm-controller run the uninstall and remove the release's resources. The envtest suite runs on every pull request: a new `make test-controllers-envtest` target builds a pinned `setup-envtest` and fetches a kube-apiserver and etcd into `_out/envtest`, which CI caches and the target reuses without asking the release index, takes the HelmRelease CRD from the in-tree Flux manifests, and CI calls it next to `make test-controllers`; the control plane gets a longer start timeout because it starts beside the other test goals. The drain is held there too: it aborts a live recovery, carries a delete through the uninstall and lifts the fence only once helm-controller has observed the unsuspended generation, keeps the fence when helm-controller never answers, releases a fence left without a suspension at once, and leaves another manager's suspension alone. `TestEnvtest_TheNextFluxPlungerLeadsOnlyAfterTheDrain` runs two real managers on one Lease: a clean stop still drains, and the second manager becomes leader only after the first one's drain has ended; it goes red if the Lease is given up on stop. Unit tests cover the controller logic (every branch, ordering, requeue, and the ownership decision through an injected seam), the Lease timing relations, that only a leader drains and through the manager's API reader rather than its stopped cache, that a failed listing is retried, that a stop which overran its grace period is still drained and its events reach the apiserver, and contract tests tie `main.go`, the chart's flags, the drain's arithmetic and the hook's names to the Go code. The pre-delete hook is covered by helm-unittest and by `hack/flux-plunger-fence-hook_test.bats`, which runs its rendered script against a fake `kubectl` that keeps each release's finalizers, suspension owner, generation and observed generation, bumps the generation on a spec write as the apiserver does, answers NotFound without `--ignore-not-found`, spends simulated time on waits, lists a release once however many copies of the fence it carries, refuses `kubectl apply`, lifts a suspension only through the preconditioned JSON patch and never one another manager also holds, reads a negative `kubectl wait` timeout as a week as kubectl does, and applies a finalizer removal only when it is the guarded test-then-remove at an index that holds the fence. Every mutation in a set covering each predicate conjunct, each retry, each exit path, the re-listing, the timings and the selector turns the hook suite red, as does every mutation in the Go set covering the drain's branches, the Lease timings and the events; three drain mutations that still survive are tracked in #4782. The hook script was also run as a Job in the hook's own image on a live cluster, succeeding, with the Deployment already gone, and with patch denied by RBAC, where it exited non-zero and named the release it left; that run caught that a per-call `--request-timeout` makes kubectl drop its in-cluster config, so the hook sets none and the fake rejects it. A later live run caught `kubectl apply --server-side` stripping the finalizers and spec of a release created by a client-side apply; with the JSON patch the same releases kept every field, the suspension flux-plunger alone held was lifted, a co-owned and a foreign one stayed, and every fence went. ### Remaining limitations - A delete that arrives after recovery has deleted the storage Secret of a release whose only revision was that one finds no revision to uninstall; helm-controller then treats the release as already gone. - A writer that sets `spec.suspend: true` while flux-plunger already holds it at `true` does not take the field over, because the value does not change. If such a writer then deletes the release inside the recovery window (the suspend-then-delete that the tenant delete hook and some platform migrations use to skip the uninstall), flux-plunger still sees its own suspension, lifts it, and helm-controller runs the uninstall that writer meant to skip. The same held before this change, when the end of recovery unsuspended unconditionally. - The already-processed guard compares revision numbers only. When Helm re-creates a revision under the same number after recovery deleted it (a release whose only revision fails again the same way), recovery runs again for it. - `listHelmReleaseSecrets` reads the local cluster only, so a HelmRelease that targets a remote cluster via `spec.kubeConfig` (whose storage Secrets live in the remote cluster) is not recovered; it is skipped, never mis-handled. - A new flux-plunger pod waits for the old one's Lease to run out before it acts, on every restart and after a crash: a little under two minutes at the default. Recovery is not latency-sensitive, and this is what keeps a single writer while the old pod drains. - The leader Lease is left in the release namespace after the chart is uninstalled, as with any controller-runtime leader election; it is inert. ### Screenshots Not applicable: no UI change. ### Downstream repositories The trigger map was walked against the diff: it touches `internal/controller/fluxplunger`, `cmd/flux-plunger`, the `packages/system/flux-plunger` chart (templates including RBAC for the leader Lease, a pre-delete hook, values, tests, its package `Makefile`, README), a new bats test under `hack/`, the root `Makefile` (a new `test-controllers-envtest` target; existing targets are unchanged) and the pull-request workflow that calls it and caches its binaries. No row matches: ccp gates on existing `hack/` files and make targets, and nothing there is moved, renamed or changed in behaviour; a new test file and a new target reach none of them. The website's FluxPlunger section describes the recovery steps, which still hold; it does not describe the fence or the drain, which the chart README now documents. - [x] No downstream repository is affected by this change - [ ] [cozystack/website](https://github.com/cozystack/website) - follow-up: - [ ] [cozystack/terraform-provider-cozystack](https://github.com/cozystack/terraform-provider-cozystack) - follow-up: - [ ] [cozystack/ansible-cozystack](https://github.com/cozystack/ansible-cozystack) - follow-up: - [ ] [cozystack/ccp](https://github.com/cozystack/ccp) - follow-up: - [ ] [cozystack/talm](https://github.com/cozystack/talm) - follow-up: - [ ] [cozystack/cozyhr](https://github.com/cozystack/cozyhr) - follow-up: - [ ] [cozystack/cozy-proxy](https://github.com/cozystack/cozy-proxy) - follow-up: - [ ] [cozystack/cozystack-telemetry-server](https://github.com/cozystack/cozystack-telemetry-server) - follow-up: - [ ] [cozystack/external-apps-example](https://github.com/cozystack/external-apps-example) - follow-up: - [ ] [cozystack/examples](https://github.com/cozystack/examples) - follow-up: - [ ] [cozystack/community](https://github.com/cozystack/community) - follow-up: ### Release note ```release-note fix(fluxcd): a HelmRelease deleted while flux-plunger is recovering it now reaches the Helm uninstall instead of leaving its resources (DataVolume, PVCs, RBAC, storage Secret) behind ```