chore: Describe RBAC rules, remove unnecessary rules (#953)

* chore: Describe RBAC rules, remove unnecessary rules

* chore: Update changelog

* chore: Remove the get for customresourcedefinitions for the operator clusterrole.

* chore: Remove the nodes list/watch rule for the operator clusterrole.

* chore: Add comment to the rule that was missing one

* chore: Remove the configmaps/secrets/serviceaccounts/services get rule for the product clusterrole

* fix: Always allow list/watch on customresourcedefinitions for the operator

Note: required by the startup condition regardless of crd maintenance

* chore: Simplify RBAC rule descriptions

* chore: Remove the events.k8s.io rule from the product ClusterRole. The operator manages the Kubernetes events.

* chore: Keep the rbac.authorization.k8s.io rules within a ClusterRole close to each other

* chore: Split the roles.yaml into separate files for clusterrole-operator.yaml and clusterrole-product.yaml

* chore(nix): Update crate hashes

* Update CHANGELOG.md

Author: NickLarsenNZ

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+### Changed
+
+- Document Helm deployed RBAC permissions and remove unnecessary permissions ([#953]).
+
+[#953]: https://github.com/stackabletech/kafka-operator/pull/953
+
 ## [26.3.0] - 2026-03-16
 
 ## [26.3.0-rc1] - 2026-03-16

Cargo.nix

@@ -6,37 +6,30 @@ metadata:
   labels:
   {{- include "operator.labels" . | nindent 4 }}
 rules:
-  - apiGroups:
-      - ""
-    resources:
-      - nodes
-    verbs:
-      - list
-      - watch
   # For automatic cluster domain detection
   - apiGroups:
       - ""
     resources:
       - nodes/proxy
     verbs:
       - get
+  # Manage core namespaced resources created per KafkaCluster.
+  # Applied via SSA and tracked for orphan cleanup.
   - apiGroups:
       - ""
     resources:
-      - pods
       - configmaps
-      - secrets
       - services
-      - endpoints
       - serviceaccounts
     verbs:
       - create
       - delete
       - get
       - list
       - patch
-      - update
       - watch
+  # RoleBinding created per KafkaCluster to bind the product ClusterRole to the workload
+  # ServiceAccount. Applied via SSA and tracked for orphan cleanup.
   - apiGroups:
       - rbac.authorization.k8s.io
     resources:
@@ -47,32 +40,30 @@ rules:
       - get
       - list
       - patch
-      - update
       - watch
+  # Required to bind the product ClusterRole to the per-cluster ServiceAccount.
   - apiGroups:
-      - apps
+      - rbac.authorization.k8s.io
     resources:
-      - statefulsets
+      - clusterroles
     verbs:
-      - get
-      - create
-      - delete
-      - list
-      - patch
-      - update
-      - watch
+      - bind
+    resourceNames:
+      - {{ include "operator.name" . }}-clusterrole
+  # StatefulSet created per role group (broker, KRaft controller). Applied via
+  # SSA, tracked for orphan cleanup, and owned by the controller.
   - apiGroups:
-      - batch
+      - apps
     resources:
-      - jobs
+      - statefulsets
     verbs:
       - create
       - delete
       - get
       - list
       - patch
-      - update
       - watch
+  # PodDisruptionBudget created per role group. Applied via SSA and tracked for orphan cleanup.
   - apiGroups:
       - policy
     resources:
@@ -83,103 +74,62 @@ rules:
       - get
       - list
       - patch
-      - update
-      - watch
+  # Required for maintaining the CRDs within the operator (including the conversion webhook info).
+  # Also for the startup condition check before the controller can run.
   - apiGroups:
       - apiextensions.k8s.io
     resources:
       - customresourcedefinitions
     verbs:
-      - get
       # Required to maintain the CRD. The operator needs to do this, as it needs to enter e.g. it's
       # generated certificate in the conversion webhook.
       {{- if .Values.maintenance.customResourceDefinitions.maintain }}
       - create
       - patch
+      {{- end }}
       # Required for startup condition
       - list
       - watch
-      {{- end }}
+  # Required to report reconciliation results and warnings back to the KafkaCluster object.
   - apiGroups:
       - events.k8s.io
     resources:
       - events
     verbs:
       - create
       - patch
+  # Primary CRD: watched by the controller and read during reconciliation.
   - apiGroups:
       - {{ include "operator.name" . }}.stackable.tech
     resources:
       - {{ include "operator.name" . }}clusters
     verbs:
       - get
       - list
-      - patch
       - watch
+  # Status subresource: updated at the end of every reconciliation.
   - apiGroups:
       - {{ include "operator.name" . }}.stackable.tech
     resources:
       - {{ include "operator.name" . }}clusters/status
     verbs:
       - patch
+  # Read authentication class configuration referenced in the KafkaCluster spec.
   - apiGroups:
       - authentication.stackable.tech
     resources:
       - authenticationclasses
     verbs:
       - get
-      - list
-      - watch
+  # Listener created per role group. Applied via SSA and tracked for orphan cleanup.
   - apiGroups:
       - listeners.stackable.tech
     resources:
       - listeners
     verbs:
-      - get
-      - list
-      - watch
-      - patch
       - create
       - delete
-  - apiGroups:
-      - rbac.authorization.k8s.io
-    resources:
-      - clusterroles
-    verbs:
-      - bind
-    resourceNames:
-      - {{ include "operator.name" . }}-clusterrole
----
-apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRole
-metadata:
-  name: {{ include "operator.name" . }}-clusterrole
-  labels:
-  {{- include "operator.labels" . | nindent 4 }}
-rules:
-  - apiGroups:
-      - ""
-    resources:
-      - configmaps
-      - secrets
-      - serviceaccounts
-      - services
-    verbs:
       - get
-  - apiGroups:
-      - events.k8s.io
-    resources:
-      - events
-    verbs:
-      - create
+      - list
       - patch
-{{ if .Capabilities.APIVersions.Has "security.openshift.io/v1" }}
-  - apiGroups:
-      - security.openshift.io
-    resources:
-      - securitycontextconstraints
-    resourceNames:
-      - nonroot-v2
-    verbs:
-      - use
-{{ end }}
+      - watch

crate-hashes.json

@@ -0,0 +1,21 @@
+---
+# Product ClusterRole: bound (via per KafkaCluster RoleBinding) to the ServiceAccount that Kafka
+# workload pods (brokers, KRaft controllers) run as.
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: {{ include "operator.name" . }}-clusterrole
+  labels:
+  {{- include "operator.labels" . | nindent 4 }}
+rules:
+{{ if .Capabilities.APIVersions.Has "security.openshift.io/v1" }}
+  # On OpenShift, the workload pods must be allowed to use the nonroot-v2 SCC
+  - apiGroups:
+      - security.openshift.io
+    resources:
+      - securitycontextconstraints
+    resourceNames:
+      - nonroot-v2
+    verbs:
+      - use
+{{ end }}