on sync compare pgVersion with SpiloConfiguration

pkg/cluster/k8sres.go

@@ -26,7 +26,7 @@ import (
 )
 
 const (
-	pgBinariesLocationTemplate       = "/usr/lib/postgresql/%s/bin"
+	pgBinariesLocationTemplate       = "/usr/lib/postgresql/%v/bin"
 	patroniPGBinariesParameterName   = "bin_dir"
 	patroniPGParametersParameterName = "parameters"
 	patroniPGHBAConfParameterName    = "pg_hba"
@@ -716,6 +716,55 @@ func makeResources(cpuRequest, memoryRequest, cpuLimit, memoryLimit string) acid
 	}
 }
 
+func extractPgVersionFromBinPath(binPath string, template string) (string, error) {
+	var pgVersion float32
+	_, err := fmt.Sscanf(binPath, template, &pgVersion)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%v", pgVersion), nil
+}
+
+func (c *Cluster) getNewPgVersion(containers []v1.Container, newPgVersion string) (string, error) {
+	var (
+		spiloConfiguration spiloConfiguration
+		runningPgVersion   string
+		err                error
+	)
+
+	for _, container := range containers {
+		if container.Name != "postgres" {
+			continue
+		}
+		for _, env := range container.Env {
+			if env.Name != "SPILO_CONFIGURATION" {
+				continue
+			}
+			err = json.Unmarshal([]byte(env.Value), &spiloConfiguration)
+			if err != nil {
+				return newPgVersion, err
+			}
+		}
+	}
+
+	if len(spiloConfiguration.PgLocalConfiguration) > 0 {
+		currentBinPath := fmt.Sprintf("%v", spiloConfiguration.PgLocalConfiguration[patroniPGBinariesParameterName])
+		runningPgVersion, err = extractPgVersionFromBinPath(currentBinPath, pgBinariesLocationTemplate)
+		if err != nil {
+			return "", fmt.Errorf("could not extract Postgres version from %v in SPILO_CONFIGURATION", currentBinPath)
+		}
+	} else {
+		return "", fmt.Errorf("could not find %q setting in SPILO_CONFIGURATION", patroniPGBinariesParameterName)
+	}
+
+	if runningPgVersion != newPgVersion {
+		c.logger.Warningf("postgresql version change(%q -> %q) has no effect", runningPgVersion, newPgVersion)
+		newPgVersion = runningPgVersion
+	}
+
+	return newPgVersion, nil
+}
+
 func (c *Cluster) generateStatefulSet(spec *acidv1.PostgresSpec) (*appsv1.StatefulSet, error) {
 
 	var (

pkg/cluster/sync.go

@@ -23,7 +23,6 @@ func (c *Cluster) Sync(newSpec *acidv1.Postgresql) error {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 
-	currentPgVersion := c.Spec.PostgresqlParam.PgVersion
 	c.setSpec(newSpec)
 
 	defer func() {
@@ -35,12 +34,6 @@ func (c *Cluster) Sync(newSpec *acidv1.Postgresql) error {
 		}
 	}()
 
-	if currentPgVersion != newSpec.Spec.PostgresqlParam.PgVersion { // PG versions comparison
-		c.logger.Warningf("postgresql version change(%q -> %q) has no effect", currentPgVersion, newSpec.Spec.PostgresqlParam.PgVersion)
-		// we need that hack to generate statefulset with the old version
-		newSpec.Spec.PostgresqlParam.PgVersion = currentPgVersion
-	}
-
 	if err = c.initUsers(); err != nil {
 		err = fmt.Errorf("could not init users: %v", err)
 		return err
@@ -292,6 +285,13 @@ func (c *Cluster) syncStatefulSet() error {
 		// statefulset is already there, make sure we use its definition in order to compare with the spec.
 		c.Statefulset = sset
 
+		// check if there is no Postgres version mismatch
+		pgVersion, err := c.getNewPgVersion(c.Statefulset.Spec.Template.Spec.Containers, c.Spec.PostgresqlParam.PgVersion)
+		if err != nil {
+			return fmt.Errorf("could not parse current Postgres version: %v", err)
+		}
+		c.Spec.PostgresqlParam.PgVersion = pgVersion
+
 		desiredSS, err := c.generateStatefulSet(&c.Spec)
 		if err != nil {
 			return fmt.Errorf("could not generate statefulset: %v", err)