extend RBAC in prepatation to switch to configmap-based cluster management (#2961)

Author: FxKu

docs/reference/operator_parameters.md

@@ -107,8 +107,13 @@ Those are top-level keys, containing both leaf keys and groups.
 * **kubernetes_use_configmaps**
   Select if setup uses endpoints (default), or configmaps to manage leader when
   DCS is kubernetes (not etcd or similar). In OpenShift it is not possible to
-  use endpoints option, and configmaps is required. By default,
-  `kubernetes_use_configmaps: false`, meaning endpoints will be used.
+  use endpoints option, and configmaps is required. Starting with K8s 1.33,
+  endpoints are marked as deprecated. It's recommended to switch to config maps
+  instead. But, to do so make sure you scale the Postgres cluster down to just
+  one primary pod (e.g. using `max_instances` option). Otherwise, you risk
+  running into a split-brain scenario.
+  By default, `kubernetes_use_configmaps: false`, meaning endpoints will be used.
+  Starting from v1.16.0 the default will be changed to `true`.
 
 * **docker_image**
   Spilo Docker image for Postgres instances. For production, don't rely on the

manifests/operator-service-account-rbac.yaml

@@ -59,13 +59,20 @@ rules:
   - get
   - patch
   - update
-# to read configuration from ConfigMaps
+# to read configuration from ConfigMaps and help Patroni manage the cluster if endpoints are not used
 - apiGroups:
   - ""
   resources:
   - configmaps
   verbs:
+  - create
+  - delete
+  - deletecollection
   - get
+  - list
+  - patch
+  - update
+  - watch
 # to send events to the CRs
 - apiGroups:
   - ""
@@ -78,7 +85,7 @@ rules:
   - patch
   - update
   - watch
-# to manage endpoints which are also used by Patroni
+# to manage endpoints which are also used by Patroni (if it is using config maps)
 - apiGroups:
   - ""
   resources:
@@ -249,7 +256,21 @@ kind: ClusterRole
 metadata:
   name: postgres-pod
 rules:
-# Patroni needs to watch and manage endpoints
+# Patroni needs to watch and manage config maps (or endpoints)
+- apiGroups:
+  - ""
+  resources:
+  - configmaps
+  verbs:
+  - create
+  - delete
+  - deletecollection
+  - get
+  - list
+  - patch
+  - update
+  - watch
+# Patroni needs to watch and manage endpoints (or config maps)
 - apiGroups:
   - ""
   resources: