cleaner-controller

Cleaner Controller

Development Cheat Sheet

Introductory reading:

https://sdk.operatorframework.io/docs/building-operators/golang/tutorial/
https://book.kubebuilder.io/introduction.html

CRD Generation

Edit the go structs
Generate code and manifests:
```
  make generate manifests
```
(Optional) Install CRDs
```
  make install
```

Reconcile logic

Edit the controller code

Run tests

  make test

Check code coverage
```
  go tool cover -html=cover.out
```

Run controller locally (uses local k8s context authorization)
```
  make run
```

Idle Knative Service cleanup

Deletes Knative Services whose effective min-scale is "0" once all their Deployments have been at 0 replicas for longer than a configurable threshold. Effective min-scale is the template annotation autoscaling.knative.dev/min-scale when set. If Helm omitted it (numeric 0 is empty in with), the controller only treats that as zero when IDLE_KNATIVE_CLUSTER_DEFAULT_SCALE_TO_ZERO=true — set this on preview clusters whose Knative default is scale-to-zero. No ksvc patch and no ConfigMap/RBAC. Explicit min-scale: "1" still excludes the Service.

This runs alongside ConditionalTTL’s creation-timestamp TTL cleanup, not instead of it — both mechanisms are active at the same time; IDLE_KNATIVE_CLEANUP_ENABLED only turns the idle mechanism on or off. Disabled by default; opt in per cluster with env vars (no rebuild required):

Env var	Default	Description
`IDLE_KNATIVE_CLEANUP_ENABLED`	`false`	Set to `true` to also register the idle-cleanup controller.
`IDLE_KNATIVE_CLEANUP_THRESHOLD`	`12h`	Go duration string (e.g. `6h`, `30m`) a Service may stay idle before deletion.
`IDLE_KNATIVE_CLUSTER_DEFAULT_SCALE_TO_ZERO`	`false`	When `true`, missing template `min-scale` is treated as `"0"`.

Opt a specific Service out with the cleaner.vtex.io/exclude: "true" annotation. Edit the controller code.

See the architecture diagram for a visual overview of what each cleanup mechanism deletes and how the idle timer resets on scale-up (make diagram).