improve RBAC setup for postgres pods

changed the default name, updated helm chart and docs
allow role to use privileged podsecurtitypolicies

charts/postgres-operator/crds/operatorconfigurations.yaml

@@ -148,6 +148,8 @@ spec:
                   type: string
                 pod_service_account_name:
                   type: string
+                pod_service_account_role_definition:
+                  type: string
                 pod_service_account_role_binding_definition:
                   type: string
                 pod_terminate_grace_period:

charts/postgres-operator/templates/clusterrole.yaml

@@ -9,6 +9,7 @@ metadata:
     app.kubernetes.io/managed-by: {{ .Release.Service }}
     app.kubernetes.io/instance: {{ .Release.Name }}
 rules:
+# all verbs allowed for custom operator resources
 - apiGroups:
   - acid.zalan.do
   resources:
@@ -16,7 +17,15 @@ rules:
   - postgresqls/status
   - operatorconfigurations
   verbs:
-  - "*"
+  - create
+  - delete
+  - deletecollection
+  - get
+  - list
+  - patch
+  - update
+  - watch
+# to create or get/update CRDs when starting up
 - apiGroups:
   - apiextensions.k8s.io
   resources:
@@ -26,12 +35,14 @@ rules:
   - get
   - patch
   - update
+# to read configuration from ConfigMaps
 - apiGroups:
   - ""
   resources:
   - configmaps
   verbs:
   - get
+# to manage endpoints which are also used by Patroni
 - apiGroups:
   - ""
   resources:
@@ -43,7 +54,9 @@ rules:
   - get
   - list
   - patch
-  - watch  # needed if zalando-postgres-operator account is used for pods as well
+  - update
+  - watch
+# to CRUD secrets for database access
 - apiGroups:
   - ""
   resources:
@@ -53,6 +66,7 @@ rules:
   - update
   - delete
   - get
+# to check nodes for node readiness label
 - apiGroups:
   - ""
   resources:
@@ -61,6 +75,7 @@ rules:
   - get
   - list
   - watch
+# to read or delete existing PVCs. Creation via StatefulSet
 - apiGroups:
   - ""
   resources:
@@ -69,6 +84,7 @@ rules:
   - delete
   - get
   - list
+ # to read existing PVs. Creation should be done via dynamic provisioning
 - apiGroups:
   - ""
   resources:
@@ -77,6 +93,7 @@ rules:
   - get
   - list
   - update  # only for resizing AWS volumes
+# to watch Spilo pods and do rolling updates. Creation via StatefulSet
 - apiGroups:
   - ""
   resources:
@@ -85,14 +102,17 @@ rules:
   - delete
   - get
   - list
-  - watch
   - patch
+  - update
+  - watch
+# to resize the filesystem in Spilo pods when increasing volume size
 - apiGroups:
   - ""
   resources:
   - pods/exec
   verbs:
   - create
+# to CRUD services to point to Postgres cluster instances
 - apiGroups:
   - ""
   resources:
@@ -102,6 +122,7 @@ rules:
   - delete
   - get
   - patch
+# to CRUD the StatefulSet which controls the Postgres cluster instances
 - apiGroups:
   - apps
   resources:
@@ -112,12 +133,26 @@ rules:
   - get
   - list
   - patch
+# to CRUD cron jobs for logical backups
+- apiGroups:
+  - batch
+  resources:
+  - cronjobs
+  verbs:
+  - create
+  - delete
+  - get
+  - list
+  - patch
+  - update
+# to get namespaces operator resources can run in
 - apiGroups:
   - ""
   resources:
   - namespaces
   verbs:
   - get
+# to define PDBs. Update happens via delete/create
 - apiGroups:
   - policy
   resources:
@@ -126,6 +161,7 @@ rules:
   - create
   - delete
   - get
+# to create ServiceAccounts in each namespace the operator watches
 - apiGroups:
   - ""
   resources:
@@ -133,30 +169,22 @@ rules:
   verbs:
   - get
   - create
+# to create roles and role bindings to the pod service account
 - apiGroups:
-  - "rbac.authorization.k8s.io"
+  - rbac.authorization.k8s.io
   resources:
   - rolebindings
+  - roles
   verbs:
   - get
   - create
+# needed to grant to namespaced roles when pods run in privileged mode
 - apiGroups:
-  - "rbac.authorization.k8s.io"
+  - extensions
   resources:
-  - clusterroles
+  - podsecuritypolicies
-  verbs:
-  - bind
   resourceNames:
-  - {{ include "postgres-operator.serviceAccountName" . }}
+  - privileged
-- apiGroups:
-  - batch
-  resources:
-  - cronjobs  # enables logical backups
   verbs:
-  - create
+  - use
-  - delete
-  - get
-  - list
-  - patch
-  - update
 {{ end }}

charts/postgres-operator/templates/clusterrolebinding.yaml

@@ -14,8 +14,6 @@ roleRef:
   name: {{ include "postgres-operator.serviceAccountName" . }}
 subjects:
 - kind: ServiceAccount
-# note: the cluster role binding needs to be defined
-# for every namespace the operator service account lives in.
   name: {{ include "postgres-operator.serviceAccountName" . }}
   namespace: {{ .Release.Namespace }}
 {{ end }}

charts/postgres-operator/templates/configmap.yaml

@@ -9,7 +9,6 @@ metadata:
     app.kubernetes.io/managed-by: {{ .Release.Service }}
     app.kubernetes.io/instance: {{ .Release.Name }}
 data:
-  pod_service_account_name: {{ include "postgres-operator.serviceAccountName" . }}
 {{ toYaml .Values.configGeneral | indent 2 }}
 {{ toYaml .Values.configUsers | indent 2 }}
 {{ toYaml .Values.configKubernetes | indent 2 }}

charts/postgres-operator/templates/operatorconfiguration.yaml

@@ -14,7 +14,6 @@ configuration:
 {{ toYaml .Values.configUsers | indent 4 }}
   kubernetes:
     oauth_token_secret_name: {{ template "postgres-operator.fullname" . }}
-    pod_service_account_name: {{ include "postgres-operator.serviceAccountName" . }}
 {{ toYaml .Values.configKubernetes | indent 4 }}
   postgres_pod_resources:
 {{ toYaml .Values.configPostgresPodResources | indent 4 }}

charts/postgres-operator/values-crd.yaml

@@ -100,6 +100,17 @@ configKubernetes:
   pod_management_policy: "ordered_ready"
   # label assigned to the Postgres pods (and services/endpoints)
   pod_role_label: spilo-role
+  # service account definition as JSON/YAML string to be used by postgres cluster pods
+  # pod_service_account_definition: ""
+
+  # name of service account to be used by postgres cluster pods
+  pod_service_account_name: "postgres-pod"
+  # role definition as JSON/YAML string to be used by postgres cluster pods
+  # pod_service_account_role_definition: ""
+
+  # role binding definition as JSON/YAML string to be used by pod service account
+  # pod_service_account_role_binding_definition: ""
+
   # Postgres pods are terminated forcefully after this timeout
   pod_terminate_grace_period: 5m
   # template for database user secrets generated by the operator

charts/postgres-operator/values.yaml

@@ -93,6 +93,17 @@ configKubernetes:
   pod_management_policy: "ordered_ready"
   # label assigned to the Postgres pods (and services/endpoints)
   pod_role_label: spilo-role
+  # service account definition as JSON/YAML string to be used by postgres cluster pods
+  # pod_service_account_definition: ""
+
+  # name of service account to be used by postgres cluster pods
+  pod_service_account_name: "postgres-pod"
+  # role definition as JSON/YAML string to be used by postgres cluster pods
+  # pod_service_account_role_definition: ""
+
+  # role binding definition as JSON/YAML string to be used by pod service account
+  # pod_service_account_role_binding_definition: ""
+
   # Postgres pods are terminated forcefully after this timeout
   pod_terminate_grace_period: 5m
   # template for database user secrets generated by the operator

docs/administrator.md

@@ -47,6 +47,12 @@ patching the CRD manifest:
 zk8 patch crd postgresqls.acid.zalan.do -p '{"spec":{"validation": null}}'
 ```
 
+## Non-default cluster domain
+
+If your cluster uses a DNS domain other than the default `cluster.local`, this
+needs to be set in the operator configuration (`cluster_domain` variable). This
+is used by the operator to connect to the clusters after creation.
+
 ## Namespaces
 
 ### Select the namespace to deploy to
@@ -89,30 +95,6 @@ lacks access rights to any of them (except K8s system namespaces like
 'list pods' execute at the cluster scope and fail at the first violation of
 access rights.
 
-The watched namespace also needs to have a (possibly different) service account
-in the case database pods need to talk to the K8s API (e.g. when using
-K8s-native configuration of Patroni). The operator checks that the
-`pod_service_account_name` exists in the target namespace, and, if not, deploys
-there the `pod_service_account_definition` from the operator
-[`Config`](../pkg/util/config/config.go) with the default value of:
-
-```yaml
-apiVersion: v1
-kind: ServiceAccount
-metadata:
- name: operator
-```
-
-In this definition, the operator overwrites the account's name to match
-`pod_service_account_name` and the `default` namespace to match the target
-namespace. The operator performs **no** further syncing of this account.
-
-## Non-default cluster domain
-
-If your cluster uses a DNS domain other than the default `cluster.local`, this
-needs to be set in the operator configuration (`cluster_domain` variable). This
-is used by the operator to connect to the clusters after creation.
-
 ## Role-based access control for the operator
 
 The manifest [`operator-service-account-rbac.yaml`](../manifests/operator-service-account-rbac.yaml)
@@ -127,14 +109,19 @@ kubectl create -f manifests/postgres-operator.yaml
 kubectl create -f manifests/minimal-postgres-manifest.yaml
 ```
 
-### Service account and cluster roles
+### Namespaced service account and roles
 
-Note that the service account is named `zalando-postgres-operator`. You may have
+For each namespace the operator watches it creates (or reads) a service account
-to change the `service_account_name` in the operator ConfigMap and
+to be used by the Postgres Pods when a new cluster is deployed. This service
-`serviceAccountName` in the `postgres-operator` deployment appropriately. This
+account is bound to a namespaced Role via RoleBinding, which are also created
-is done intentionally to avoid breaking those setups that already work with the
+(or read) by the operator. The name and definitions of these resources can be
-default `operator` account. In the future the operator should ideally be run
+[configured](reference/operator_parameters.md#kubernetes-resources).
-under the `zalando-postgres-operator` service account.
+Note, that the operator performs **no** further syncing of them.
+
+Until v1.3.1, RoleBindings pointed to the operator ClusterRole by default. This
+can still be configured but is not recommended as the Postgres Pods should only
+run with the least privileges required for Patroni to work. By default, the
+namespaced RBAC resources are named `postgres-pod`.
 
 ### Give K8s users access to create/list `postgresqls`
 

docs/reference/operator_parameters.md

@@ -152,21 +152,29 @@ configuration they are grouped under the `kubernetes` key.
   service account used by Patroni running on individual Pods to communicate
   with the operator. Required even if native Kubernetes support in Patroni is
   not used, because Patroni keeps pod labels in sync with the instance role.
-  The default is `operator`.
+  The default is `postgres-pod`.
 
 * **pod_service_account_definition**
-  The operator tries to create the pod Service Account in the namespace that
+  on Postgres cluster creation the operator tries to create the service account
-  doesn't define such an account using the YAML definition provided by this
+  for the Postgres pods if it does not exist in the namespace. The internal
-  option. If not defined, a simple definition that contains only the name will
+  default service account definition (defines only the name) can be overwritten
-  be used. The default is empty.
+  with this parameter. Make sure to provide a valid YAML or JSON string. The
+  default is empty.
+
+* **pod_service_account_role_definition**
+  operator will try to create a role in the namespace to be used by pod service
+  account. The internal default definition contains permissions to manage pods
+  and endpoints necessary for Patroni to work. Therefore, when overwriting the
+  definition with this parameter make sure to provide sufficient access rights
+  in a valid YAML/JSON string. The default is empty.
 
 * **pod_service_account_role_binding_definition**
-  This definition must bind pod service account to a role with permission
+  the created service account and role are referenced with a role binding. When
-  sufficient for the pods to start and for Patroni to access K8s endpoints;
+  overwriting its definition with this parameters using a valid YAML/JSON string
-  service account on its own lacks any such rights starting with K8s v1.8. If
+  check that the specified service account and role either exist in the K8s
-  not explicitly defined by the user, a simple definition that binds the
+  cluster or will be created by the operator. While it's possible to also
-  account to the operator's own 'zalando-postgres-operator' cluster role will
+  reference cluster roles, the binding itself can only be of kind `RoleBinding`,
-  be used. The default is empty.
+  not `ClusterRoleBinding`. The default is empty.
 
 * **pod_terminate_grace_period**
   Postgres pods are [terminated forcefully](https://kubernetes.io/docs/concepts/workloads/pods/pod/#termination-of-pods)

manifests/configmap.yaml

@@ -63,7 +63,10 @@ data:
   pod_label_wait_timeout: 10m
   pod_management_policy: "ordered_ready"
   pod_role_label: spilo-role
-  pod_service_account_name: "zalando-postgres-operator"
+  # pod_service_account_definition: ""
+  pod_service_account_name: "postgres-pod"
+  # pod_service_account_role_definition: ""
+  # pod_service_account_role_binding_definition: '{"apiVersion":"rbac.authorization.k8s.io/v1","kind":"RoleBinding","metadata":{"name":"postgres-pod"},"roleRef":{"apiGroup":"rbac.authorization.k8s.io","kind": "ClusterRole","name": "postgres-pod"},"subjects":[{"kind": "ServiceAccount","name": "postgres-pod"}]}'
   pod_terminate_grace_period: 5m
   # postgres_superuser_teams: "postgres_superusers"
   # protected_role_names: "admin"

manifests/operator-service-account-rbac.yaml

@@ -1,14 +1,14 @@
 apiVersion: v1
 kind: ServiceAccount
 metadata:
-  name: zalando-postgres-operator
+  name: postgres-operator
   namespace: default
 
 ---
 apiVersion: rbac.authorization.k8s.io/v1
 kind: ClusterRole
 metadata:
-  name: zalando-postgres-operator
+  name: postgres-operator
 rules:
 # all verbs allowed for custom operator resources
 - apiGroups:
@@ -18,7 +18,14 @@ rules:
   - postgresqls/status
   - operatorconfigurations
   verbs:
-  - "*"
+  - create
+  - delete
+  - deletecollection
+  - get
+  - list
+  - patch
+  - update
+  - watch
 # to create or get/update CRDs when starting up
 - apiGroups:
   - apiextensions.k8s.io
@@ -48,7 +55,8 @@ rules:
   - get
   - list
   - patch
-  - watch  # needed if zalando-postgres-operator account is used for pods as well
+  - update
+  - watch
 # to CRUD secrets for database access
 - apiGroups:
   - ""
@@ -95,8 +103,9 @@ rules:
   - delete
   - get
   - list
-  - watch
   - patch
+  - update
+  - watch
 # to resize the filesystem in Spilo pods when increasing volume size
 - apiGroups:
   - ""
@@ -126,6 +135,18 @@ rules:
   - get
   - list
   - patch
+# to CRUD cron jobs for logical backups
+- apiGroups:
+  - batch
+  resources:
+  - cronjobs
+  verbs:
+  - create
+  - delete
+  - get
+  - list
+  - patch
+  - update
 # to get namespaces operator resources can run in
 - apiGroups:
   - ""
@@ -150,39 +171,35 @@ rules:
   verbs:
   - get
   - create
-# to create role bindings to the operator service account
+# to create roles and role bindings to the pod service account
 - apiGroups:
-  - "rbac.authorization.k8s.io"
+  - rbac.authorization.k8s.io
   resources:
   - rolebindings
+  - roles
   verbs:
   - get
   - create
-# to CRUD cron jobs for logical backups
+# needed to grant to namespaced roles when pods run in privileged mode
 - apiGroups:
-  - batch
+  - extensions
   resources:
-  - cronjobs
+  - podsecuritypolicies
+  resourceNames:
+  - privileged
   verbs:
-  - create
+  - use
-  - delete
-  - get
-  - list
-  - patch
-  - update
 
 ---
 apiVersion: rbac.authorization.k8s.io/v1
 kind: ClusterRoleBinding
 metadata:
-  name: zalando-postgres-operator
+  name: postgres-operator
 roleRef:
   apiGroup: rbac.authorization.k8s.io
   kind: ClusterRole
-  name: zalando-postgres-operator
+  name: postgres-operator
 subjects:
 - kind: ServiceAccount
-# note: the cluster role binding needs to be defined
+  name: postgres-operator
-# for every namespace the operator service account lives in.
-  name: zalando-postgres-operator
   namespace: default

manifests/operatorconfiguration.crd.yaml

@@ -124,6 +124,8 @@ spec:
                   type: string
                 pod_service_account_name:
                   type: string
+                pod_service_account_role_definition:
+                  type: string
                 pod_service_account_role_binding_definition:
                   type: string
                 pod_terminate_grace_period:

manifests/postgres-operator.yaml

@@ -12,7 +12,7 @@ spec:
       labels:
         name: postgres-operator
     spec:
-      serviceAccountName: zalando-postgres-operator
+      serviceAccountName: postgres-operator
       containers:
       - name: postgres-operator
         image: registry.opensource.zalan.do/acid/postgres-operator:v1.3.1

manifests/postgres-pod-rbac.yaml

@@ -0,0 +1,49 @@
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: postgres-pod
+  namespace: default
+
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: postgres-pod
+rules:
+- apiGroups:
+  - ""
+  resources:
+  - endpoints
+  verbs:
+  - create
+  - delete
+  - deletecollection
+  - get
+  - list
+  - patch
+  - update
+  - watch
+- apiGroups:
+  - ""
+  resources:
+  - pods
+  verbs:
+  - get
+  - list
+  - patch
+  - update
+  - watch
+- apiGroups:
+  - ""
+  resources:
+  - services
+  verbs:
+  - create
+- apiGroups:
+  - extensions
+  resources:
+  - podsecuritypolicies
+  resourceNames:
+  - privileged
+  verbs:
+  - use

manifests/postgresql-operator-default-configuration.yaml

@@ -45,7 +45,8 @@ configuration:
     # pod_priority_class_name: ""
     pod_role_label: spilo-role
     # pod_service_account_definition: ""
-    pod_service_account_name: zalando-postgres-operator
+    pod_service_account_name: postgres-pod
+    # pod_service_account_role_definition: ""
     # pod_service_account_role_binding_definition: ""
     pod_terminate_grace_period: 5m
     secret_name_template: "{username}.{cluster}.credentials.{tprkind}.{tprgroup}"

manifests/user-facing-clusterroles.yaml

@@ -11,7 +11,14 @@ rules:
   - postgresqls
   - postgresqls/status
   verbs:
-  - "*"
+  - create
+  - delete
+  - deletecollection
+  - get
+  - list
+  - patch
+  - update
+  - watch
 
 ---
 apiVersion: rbac.authorization.k8s.io/v1
@@ -48,4 +55,3 @@ rules:
   - get
   - list
   - watch
-

pkg/apis/acid.zalan.do/v1/crds.go

@@ -771,6 +771,9 @@ var OperatorConfigCRDResourceValidation = apiextv1beta1.CustomResourceValidation
 							"pod_service_account_name": {
 								Type: "string",
 							},
+							"pod_service_account_role_definition": {
+								Type: "string",
+							},
 							"pod_service_account_role_binding_definition": {
 								Type: "string",
 							},

pkg/apis/acid.zalan.do/v1/operator_configuration_type.go

@@ -43,6 +43,7 @@ type KubernetesMetaConfiguration struct {
 	PodServiceAccountName string `json:"pod_service_account_name,omitempty"`
 	// TODO: change it to the proper json
 	PodServiceAccountDefinition            string                `json:"pod_service_account_definition,omitempty"`
+	PodServiceAccountRoleDefinition        string                `json:"pod_service_account_role_definition,omitempty"`
 	PodServiceAccountRoleBindingDefinition string                `json:"pod_service_account_role_binding_definition,omitempty"`
 	PodTerminateGracePeriod                Duration              `json:"pod_terminate_grace_period,omitempty"`
 	SpiloPrivileged                        bool                  `json:"spilo_privileged,omitempty"`

pkg/cluster/cluster.go

@@ -45,6 +45,7 @@ type Config struct {
 	RestConfig                   *rest.Config
 	InfrastructureRoles          map[string]spec.PgUser // inherited from the controller
 	PodServiceAccount            *v1.ServiceAccount
+	PodServiceAccountRole        *rbacv1.Role
 	PodServiceAccountRoleBinding *rbacv1.RoleBinding
 }
 

pkg/controller/controller.go

@@ -57,6 +57,7 @@ type Controller struct {
 	workerLogs map[uint32]ringlog.RingLogger
 
 	PodServiceAccount            *v1.ServiceAccount
+	PodServiceAccountRole        *rbacv1.Role
 	PodServiceAccountRoleBinding *rbacv1.RoleBinding
 }
 
@@ -161,11 +162,12 @@ func (c *Controller) initPodServiceAccount() {
 
 	if c.opConfig.PodServiceAccountDefinition == "" {
 		c.opConfig.PodServiceAccountDefinition = `
-		{ "apiVersion": "v1",
+		{
-		  "kind": "ServiceAccount",
+			"apiVersion": "v1",
-		  "metadata": {
+			"kind": "ServiceAccount",
-				 "name": "operator"
+			"metadata": {
-		   }
+				"name": "postgres-pod"
+			}
 		}`
 	}
 
@@ -175,13 +177,13 @@ func (c *Controller) initPodServiceAccount() {
 
 	switch {
 	case err != nil:
-		panic(fmt.Errorf("Unable to parse pod service account definition from the operator config map: %v", err))
+		panic(fmt.Errorf("Unable to parse pod service account definition from the operator configuration: %v", err))
 	case groupVersionKind.Kind != "ServiceAccount":
-		panic(fmt.Errorf("pod service account definition in the operator config map defines another type of resource: %v", groupVersionKind.Kind))
+		panic(fmt.Errorf("pod service account definition in the operator configuration defines another type of resource: %v", groupVersionKind.Kind))
 	default:
 		c.PodServiceAccount = obj.(*v1.ServiceAccount)
 		if c.PodServiceAccount.Name != c.opConfig.PodServiceAccountName {
-			c.logger.Warnf("in the operator config map, the pod service account name %v does not match the name %v given in the account definition; using the former for consistency", c.opConfig.PodServiceAccountName, c.PodServiceAccount.Name)
+			c.logger.Warnf("in the operator configuration, the pod service account name %v does not match the name %v given in the account definition; using the former for consistency", c.opConfig.PodServiceAccountName, c.PodServiceAccount.Name)
 			c.PodServiceAccount.Name = c.opConfig.PodServiceAccountName
 		}
 		c.PodServiceAccount.Namespace = ""
@@ -190,6 +192,100 @@ func (c *Controller) initPodServiceAccount() {
 	// actual service accounts are deployed at the time of Postgres/Spilo cluster creation
 }
 
+func (c *Controller) initRole() {
+
+	// service account on its own lacks any rights starting with k8s v1.8
+	// operator binds it to the namespaced role with sufficient privileges
+	if c.opConfig.PodServiceAccountRoleDefinition == "" {
+		c.opConfig.PodServiceAccountRoleDefinition = fmt.Sprintf(`
+		{
+			"apiVersion": "rbac.authorization.k8s.io/v1",
+			"kind": "Role",
+			"metadata": {
+				"name": "%s"
+			},
+			"rules": [
+		        {
+		            "apiGroups": [
+		                ""
+		            ],
+		            "resources": [
+		                "endpoints"
+		            ],
+		            "verbs": [
+		                "create",
+		                "delete",
+		                "deletecollection",
+		                "get",
+		                "list",
+		                "patch",
+		                "update",
+		                "watch"
+		            ]
+		        },
+		        {
+		            "apiGroups": [
+		                ""
+		            ],
+		            "resources": [
+		                "pods"
+		            ],
+		            "verbs": [
+		                "get",
+		                "list",
+		                "patch",
+		                "update",
+		                "watch"
+		            ]
+		        },
+		        {
+		            "apiGroups": [
+		                ""
+		            ],
+		            "resources": [
+		                "services"
+		            ],
+		            "verbs": [
+		                "create"
+		            ]
+		        },
+		        {
+		            "apiGroups": [
+		                "extensions"
+		            ],
+		            "resources": [
+		                "podsecuritypolicies"
+		            ],
+		            "resourceNames": [
+		                "privileged"
+		            ],
+		            "verbs": [
+		                "use"
+		            ]
+		        }
+		    ]
+		}`, c.PodServiceAccount.Name)
+	}
+	c.logger.Info("Parse roles")
+	// re-uses k8s internal parsing. See k8s client-go issue #193 for explanation
+	decode := scheme.Codecs.UniversalDeserializer().Decode
+	obj, groupVersionKind, err := decode([]byte(c.opConfig.PodServiceAccountRoleDefinition), nil, nil)
+
+	switch {
+	case err != nil:
+		panic(fmt.Errorf("unable to parse the role definition from the operator configuration: %v", err))
+	case groupVersionKind.Kind != "Role":
+		panic(fmt.Errorf("role definition in the operator configuration defines another type of resource: %v", groupVersionKind.Kind))
+	default:
+		c.PodServiceAccountRole = obj.(*rbacv1.Role)
+		c.PodServiceAccountRole.Namespace = ""
+		c.logger.Info("successfully parsed")
+
+	}
+
+	// actual roles bindings are deployed at the time of Postgres/Spilo cluster creation
+}
+
 func (c *Controller) initRoleBinding() {
 
 	// service account on its own lacks any rights starting with k8s v1.8
@@ -205,7 +301,7 @@ func (c *Controller) initRoleBinding() {
 			},
 			"roleRef": {
 				"apiGroup": "rbac.authorization.k8s.io",
-				"kind": "ClusterRole",
+				"kind": "Role",
 				"name": "%s"
 			},
 			"subjects": [
@@ -223,9 +319,9 @@ func (c *Controller) initRoleBinding() {
 
 	switch {
 	case err != nil:
-		panic(fmt.Errorf("Unable to parse the definition of the role binding for the pod service account definition from the operator config map: %v", err))
+		panic(fmt.Errorf("unable to parse the role binding definition from the operator configuration: %v", err))
 	case groupVersionKind.Kind != "RoleBinding":
-		panic(fmt.Errorf("role binding definition in the operator config map defines another type of resource: %v", groupVersionKind.Kind))
+		panic(fmt.Errorf("role binding definition in the operator configuration defines another type of resource: %v", groupVersionKind.Kind))
 	default:
 		c.PodServiceAccountRoleBinding = obj.(*rbacv1.RoleBinding)
 		c.PodServiceAccountRoleBinding.Namespace = ""
@@ -253,6 +349,10 @@ func (c *Controller) initController() {
 	}
 	c.initPodServiceAccount()
 	c.initRoleBinding()
+	// init role only if binding references a role
+	if c.PodServiceAccountRoleBinding != nil && c.PodServiceAccountRoleBinding.RoleRef.Kind == "Role" {
+		c.initRole()
+	}
 
 	c.modifyConfigFromEnvironment()
 

pkg/controller/operator_config.go

@@ -45,6 +45,7 @@ func (c *Controller) importConfigurationFromCRD(fromCRD *acidv1.OperatorConfigur
 	result.CustomPodAnnotations = fromCRD.Kubernetes.CustomPodAnnotations
 	result.PodServiceAccountName = fromCRD.Kubernetes.PodServiceAccountName
 	result.PodServiceAccountDefinition = fromCRD.Kubernetes.PodServiceAccountDefinition
+	result.PodServiceAccountRoleDefinition = fromCRD.Kubernetes.PodServiceAccountRoleDefinition
 	result.PodServiceAccountRoleBindingDefinition = fromCRD.Kubernetes.PodServiceAccountRoleBindingDefinition
 	result.PodEnvironmentConfigMap = fromCRD.Kubernetes.PodEnvironmentConfigMap
 	result.PodTerminateGracePeriod = time.Duration(fromCRD.Kubernetes.PodTerminateGracePeriod)

pkg/controller/postgresql.go

@@ -493,23 +493,31 @@ func (c *Controller) postgresqlDelete(obj interface{}) {
 }
 
 /*
-  Ensures the pod service account and role bindings exists in a namespace
+  Ensures the pod service account, role and role bindings exists in a namespace
   before a PG cluster is created there so that a user does not have to deploy
   these credentials manually.  StatefulSets require the service account to
   create pods; Patroni requires relevant RBAC bindings to access endpoints.
 
-  The operator does not sync accounts/role bindings after creation.
+  The operator does not sync accounts/roles/role bindings after creation.
 */
 func (c *Controller) submitRBACCredentials(event ClusterEvent) error {
 
 	namespace := event.NewSpec.GetNamespace()
 
 	if err := c.createPodServiceAccount(namespace); err != nil {
-		return fmt.Errorf("could not create pod service account %v : %v", c.opConfig.PodServiceAccountName, err)
+		return fmt.Errorf("could not create pod service account %q : %v", c.opConfig.PodServiceAccountName, err)
+	}
+
+	// create role only if binding references a role
+	// if not role is empty and we rely on an existing cluster role
+	if c.PodServiceAccountRole != nil {
+		if err := c.createRole(namespace); err != nil {
+			return fmt.Errorf("could not create role %q : %v", c.PodServiceAccountRole.Name, err)
+		}
 	}
 
 	if err := c.createRoleBindings(namespace); err != nil {
-		return fmt.Errorf("could not create role binding %v : %v", c.PodServiceAccountRoleBinding.Name, err)
+		return fmt.Errorf("could not create role binding %q : %v", c.PodServiceAccountRoleBinding.Name, err)
 	}
 	return nil
 }
@@ -517,19 +525,39 @@ func (c *Controller) submitRBACCredentials(event ClusterEvent) error {
 func (c *Controller) createPodServiceAccount(namespace string) error {
 
 	podServiceAccountName := c.opConfig.PodServiceAccountName
+	// get a separate copy of service account
+	// to prevent a race condition when setting a namespace for many clusters
+	sa := *c.PodServiceAccount
+
 	_, err := c.KubeClient.ServiceAccounts(namespace).Get(podServiceAccountName, metav1.GetOptions{})
 	if k8sutil.ResourceNotFound(err) {
-
+		c.logger.Infof(fmt.Sprintf("creating pod service account %q in the %q namespace", podServiceAccountName, namespace))
-		c.logger.Infof(fmt.Sprintf("creating pod service account in the namespace %v", namespace))
-
-		// get a separate copy of service account
-		// to prevent a race condition when setting a namespace for many clusters
-		sa := *c.PodServiceAccount
 		if _, err = c.KubeClient.ServiceAccounts(namespace).Create(&sa); err != nil {
-			return fmt.Errorf("cannot deploy the pod service account %v defined in the config map to the %v namespace: %v", podServiceAccountName, namespace, err)
+			return fmt.Errorf("cannot deploy the pod service account %q defined in the configuration to the %q namespace: %v", podServiceAccountName, namespace, err)
 		}
+		c.logger.Infof("successfully deployed the pod service account %q to the %q namespace", podServiceAccountName, namespace)
+	} else if k8sutil.ResourceAlreadyExists(err) {
+		return nil
+	}
 
-		c.logger.Infof("successfully deployed the pod service account %v to the %v namespace", podServiceAccountName, namespace)
+	return err
+}
+
+func (c *Controller) createRole(namespace string) error {
+
+	podServiceAccountRoleName := c.PodServiceAccountRole.Name
+	// get a separate copy of the role
+	// to prevent a race condition when setting a namespace for many clusters
+	role := *c.PodServiceAccountRole
+
+	_, err := c.KubeClient.Roles(namespace).Get(podServiceAccountRoleName, metav1.GetOptions{})
+	if k8sutil.ResourceNotFound(err) {
+		c.logger.Infof("creating role %q in the %q namespace", podServiceAccountRoleName, namespace)
+		_, err = c.KubeClient.Roles(namespace).Create(&role)
+		if err != nil {
+			return fmt.Errorf("cannot create role %q in the %q namespace: %v", podServiceAccountRoleName, namespace, err)
+		}
+		c.logger.Infof("successfully deployed role %q to the %q namespace", podServiceAccountRoleName, namespace)
 	} else if k8sutil.ResourceAlreadyExists(err) {
 		return nil
 	}
@@ -541,22 +569,18 @@ func (c *Controller) createRoleBindings(namespace string) error {
 
 	podServiceAccountName := c.opConfig.PodServiceAccountName
 	podServiceAccountRoleBindingName := c.PodServiceAccountRoleBinding.Name
+	// get a separate copy of role binding
+	// to prevent a race condition when setting a namespace for many clusters
+	rb := *c.PodServiceAccountRoleBinding
 
 	_, err := c.KubeClient.RoleBindings(namespace).Get(podServiceAccountRoleBindingName, metav1.GetOptions{})
 	if k8sutil.ResourceNotFound(err) {
-
+		c.logger.Infof("creating the role binding %q in the %q namespace", podServiceAccountRoleBindingName, namespace)
-		c.logger.Infof("Creating the role binding %v in the namespace %v", podServiceAccountRoleBindingName, namespace)
-
-		// get a separate copy of role binding
-		// to prevent a race condition when setting a namespace for many clusters
-		rb := *c.PodServiceAccountRoleBinding
 		_, err = c.KubeClient.RoleBindings(namespace).Create(&rb)
 		if err != nil {
-			return fmt.Errorf("cannot bind the pod service account %q defined in the config map to the cluster role in the %q namespace: %v", podServiceAccountName, namespace, err)
+			return fmt.Errorf("cannot bind the pod service account %q defined in the configuration to the cluster role in the %q namespace: %v", podServiceAccountName, namespace, err)
 		}
-
 		c.logger.Infof("successfully deployed the role binding for the pod service account %q to the %q namespace", podServiceAccountName, namespace)
-
 	} else if k8sutil.ResourceAlreadyExists(err) {
 		return nil
 	}

pkg/util/config/config.go

@@ -91,14 +91,14 @@ type Config struct {
 	Scalyr
 	LogicalBackup
 
-	WatchedNamespace string            `name:"watched_namespace"`    // special values: "*" means 'watch all namespaces', the empty string "" means 'watch a namespace where operator is deployed to'
+	WatchedNamespace      string            `name:"watched_namespace"`    // special values: "*" means 'watch all namespaces', the empty string "" means 'watch a namespace where operator is deployed to'
-	EtcdHost         string            `name:"etcd_host" default:""` // special values: the empty string "" means Patroni will use K8s as a DCS
+	EtcdHost              string            `name:"etcd_host" default:""` // special values: the empty string "" means Patroni will use K8s as a DCS
-	DockerImage      string            `name:"docker_image" default:"registry.opensource.zalan.do/acid/spilo-cdp-12:1.6-p16"`
+	DockerImage           string            `name:"docker_image" default:"registry.opensource.zalan.do/acid/spilo-cdp-12:1.6-p16"`
-	Sidecars         map[string]string `name:"sidecar_docker_images"`
+	Sidecars              map[string]string `name:"sidecar_docker_images"`
-	// default name `operator` enables backward compatibility with the older ServiceAccountName field
+	PodServiceAccountName string            `name:"pod_service_account_name" default:"postgres-pod"`
-	PodServiceAccountName string `name:"pod_service_account_name" default:"operator"`
 	// value of this string must be valid JSON or YAML; see initPodServiceAccount
 	PodServiceAccountDefinition            string            `name:"pod_service_account_definition" default:""`
+	PodServiceAccountRoleDefinition        string            `name:"pod_service_account_role_definition" default:""`
 	PodServiceAccountRoleBindingDefinition string            `name:"pod_service_account_role_binding_definition" default:""`
 	MasterPodMoveTimeout                   time.Duration     `name:"master_pod_move_timeout" default:"20m"`
 	DbHostedZone                           string            `name:"db_hosted_zone" default:"db.example.com"`

pkg/util/k8sutil/k8sutil.go

@@ -39,6 +39,7 @@ type KubernetesClient struct {
 	corev1.NamespacesGetter
 	corev1.ServiceAccountsGetter
 	appsv1.StatefulSetsGetter
+	rbacv1.RolesGetter
 	rbacv1.RoleBindingsGetter
 	policyv1beta1.PodDisruptionBudgetsGetter
 	apiextbeta1.CustomResourceDefinitionsGetter
@@ -103,6 +104,7 @@ func NewFromConfig(cfg *rest.Config) (KubernetesClient, error) {
 	kubeClient.StatefulSetsGetter = client.AppsV1()
 	kubeClient.PodDisruptionBudgetsGetter = client.PolicyV1beta1()
 	kubeClient.RESTClient = client.CoreV1().RESTClient()
+	kubeClient.RolesGetter = client.RbacV1()
 	kubeClient.RoleBindingsGetter = client.RbacV1()
 	kubeClient.CronJobsGetter = client.BatchV1beta1()