Resize volume by changing pvc size if enabled in config. (#958)

* Try to resize pvc if resizing pv has failed

* added config option to switch between storage resize strategies

* changes according to requests

* Update pkg/controller/operator_config.go

Co-authored-by: Felix Kunde <felix-kunde@gmx.de>

* enable_storage_resize documented

added examples to the default configuration and helm value files

* enable_storage_resize renamed to volume_resize_mode, off by default

* volume_resize_mode renamed to storage_resize_mode

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

* pkg/cluster/volumes.go updated

* Update docs/reference/operator_parameters.md

* Update manifests/postgresql-operator-default-configuration.yaml

* Update pkg/controller/operator_config.go

* Update pkg/util/config/config.go

* Update charts/postgres-operator/values-crd.yaml

* Update charts/postgres-operator/values.yaml

* Update docs/reference/operator_parameters.md

* added logging if no changes required

Co-authored-by: Felix Kunde <felix-kunde@gmx.de>

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

@@ -980,6 +980,20 @@ var OperatorConfigCRDResourceValidation = apiextv1beta1.CustomResourceValidation
 							"spilo_privileged": {
 								Type: "boolean",
 							},
+                                                      "storage_resize_mode": {
+								Type: "string",
+								Enum: []apiextv1beta1.JSON{
+									{
+										Raw: []byte(`"ebs"`),
+									},
+									{
+										Raw: []byte(`"pvc"`),
+									},
+									{
+										Raw: []byte(`"off"`),
+									},
+								},
+							},
 							"toleration": {
 								Type: "object",
 								AdditionalProperties: &apiextv1beta1.JSONSchemaPropsOrBool{

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

@@ -53,6 +53,7 @@ type KubernetesMetaConfiguration struct {
 	WatchedNamespace                       string                `json:"watched_namespace,omitempty"`
 	PDBNameFormat                          config.StringTemplate `json:"pdb_name_format,omitempty"`
 	EnablePodDisruptionBudget              *bool                 `json:"enable_pod_disruption_budget,omitempty"`
+	StorageResizeMode                      string                `json:"storage_resize_mode,omitempty"`
 	EnableInitContainers                   *bool                 `json:"enable_init_containers,omitempty"`
 	EnableSidecars                         *bool                 `json:"enable_sidecars,omitempty"`
 	SecretNameTemplate                     config.StringTemplate `json:"secret_name_template,omitempty"`