finish PR1544

charts/postgres-operator/crds/postgresqls.yaml

@@ -464,6 +464,13 @@ spec:
                     type: string
                   standby_port:
                     type: string
+                oneOf:
+                - required:
+                  - s3_wal_path
+                - required:
+                  - gs_wal_path
+                - required:
+                  - standby_host
               streams:
                 type: array
                 nullable: true

docs/administrator.md

@@ -1088,11 +1088,15 @@ data:
 ### Standby clusters
 
 The setup for [standby clusters](user.md#setting-up-a-standby-cluster) is very
-similar to cloning. At the moment, the operator only allows for streaming from
+similar to cloning. They can stream from a WAL archive (S3, GCS). Like with
-the S3 WAL archive of the master specified in the manifest. Like with cloning,
+cloning, if you are using [additional environment variables](#custom-pod-environment-variables)
-if you are using [additional environment variables](#custom-pod-environment-variables)
+to access your backup location you have to copy those variables and prepend
-to access your backup location you have to copy those variables and prepend the
+the `STANDBY_` prefix for Spilo to find the backups and WAL files to stream.
-`STANDBY_` prefix for Spilo to find the backups and WAL files to stream.
+
+Alternatively, standby clusters can also stream from a remote primary cluster.
+You have to specify the host address. Port is optional and defaults to 5432.
+Note, that only one of the options (`s3_wal_path`, `gs_wal_path`,
+`standby_host`) can be present under the `standby` top-level key.
 
 ## Logical backups
 

docs/reference/cluster_manifest.md

@@ -395,24 +395,22 @@ under the `clone` top-level key and do not affect the already running cluster.
 ## Standby cluster
 
 On startup, an existing `standby` top-level key creates a standby Postgres
-cluster streaming from a remote location. Either from a S3 or GCS WAL
+cluster streaming from a remote location - either from a S3 or GCS WAL
-archive or a remote primary. When both of them are set, `standby_host`
+archive or a remote primary. Only one of options is allowed and required
-takes precedence.
+if the `standby` key is present.
 
 * **s3_wal_path**
   the url to S3 bucket containing the WAL archive of the remote primary.
-  Required when the `standby` section is present even when `standby_host` is set.
 
 * **gs_wal_path**
   the url to GS bucket containing the WAL archive of the remote primary.
-  Optional, but `s3_wal_path`  or `gs_wal_path` is required.
 
 * **standby_host**
   hostname or IP address of the primary to stream from.
-  When set, `s3_wal_path` is ignored.
 
 * **standby_port**
-  TCP port on which the primary is listening for connections.
+  TCP port on which the primary is listening for connections. Patroni will
+  use `"5432"` if not set.
 
 ## Volume properties
 

manifests/postgresql.crd.yaml

@@ -462,6 +462,13 @@ spec:
                     type: string
                   standby_port:
                     type: string
+                oneOf:
+                - required:
+                  - s3_wal_path
+                - required:
+                  - gs_wal_path
+                - required:
+                  - standby_host
               streams:
                 type: array
                 nullable: true

manifests/standby-manifest.yaml

@@ -12,6 +12,6 @@ spec:
     version: "14"
   # Make this a standby cluster and provide either the s3 bucket path of source cluster or the remote primary host for continuous streaming.
   standby:
-    s3_wal_path: "s3://path/to/bucket/containing/wal/of/source/cluster/"
+    s3_wal_path: " s3://mybucket/spilo/acid-minimal-cluster/abcd1234-2a4b-4b2a-8c9c-c1234defg567/wal/14/"
-    # standby_host: ""
+    # standby_host: "acid-minimal-cluster.default"
-    # standby_port: ""
+    # standby_port: "5432"

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

@@ -721,6 +721,11 @@ var PostgresCRDResourceValidation = apiextv1.CustomResourceValidation{
 								Type: "string",
 							},
 						},
+						OneOf: []apiextv1.JSONSchemaProps{
+							apiextv1.JSONSchemaProps{Required: []string{"s3_wal_path"}},
+							apiextv1.JSONSchemaProps{Required: []string{"gs_wal_path"}},
+							apiextv1.JSONSchemaProps{Required: []string{"standby_host"}},
+						},
 					},
 					"streams": {
 						Type: "array",

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

@@ -172,8 +172,8 @@ type Patroni struct {
 
 // StandbyDescription contains remote primary config or s3 wal path
 type StandbyDescription struct {
-	S3WalPath string `json:"s3_wal_path,omitempty"`
+	S3WalPath   string `json:"s3_wal_path,omitempty"`
-	GSWalPath string `json:"gs_wal_path,omitempty"`
+	GSWalPath   string `json:"gs_wal_path,omitempty"`
 	StandbyHost string `json:"standby_host,omitempty"`
 	StandbyPort string `json:"standby_port,omitempty"`
 }

pkg/cluster/k8sres.go

@@ -762,7 +762,12 @@ func (c *Cluster) generatePodTemplate(
 }
 
 // generatePodEnvVars generates environment variables for the Spilo Pod
-func (c *Cluster) generateSpiloPodEnvVars(uid types.UID, spiloConfiguration string, cloneDescription *acidv1.CloneDescription, standbyDescription *acidv1.StandbyDescription, customPodEnvVarsList []v1.EnvVar) []v1.EnvVar {
+func (c *Cluster) generateSpiloPodEnvVars(
+	uid types.UID,
+	spiloConfiguration string,
+	cloneDescription *acidv1.CloneDescription,
+	standbyDescription *acidv1.StandbyDescription,
+	customPodEnvVarsList []v1.EnvVar) []v1.EnvVar {
 	envVars := []v1.EnvVar{
 		{
 			Name:  "SCOPE",
@@ -1111,12 +1116,6 @@ func (c *Cluster) generateStatefulSet(spec *acidv1.PostgresSpec) (*appsv1.Statef
 	sort.Slice(customPodEnvVarsList,
 		func(i, j int) bool { return customPodEnvVarsList[i].Name < customPodEnvVarsList[j].Name })
 
-	if spec.StandbyCluster != nil {
-		if spec.StandbyCluster.S3WalPath == "" && spec.StandbyCluster.GSWalPath == "" && spec.StandbyCluster.StandbyHost == "" {
-			return nil, fmt.Errorf("s3_wal_path, gs_wal_path and standby_host are empty for standby cluster")
-		}
-	}
-
 	// backward compatible check for InitContainers
 	if spec.InitContainersOld != nil {
 		msg := "manifest parameter init_containers is deprecated."