Sync clusters states

* move statefulset creation from cluster spec to the separate function
* sync cluster state with desired state;
* move out from arrays for cluster resources;
* recreate pods instead of deleting them in case of statefulset change
* check for master while creating cluster/updating pods
* simplify retryutil
* list pvc while listing resources
* name kubernetes resources with capital letter
* do rolling update in case of env variables change

pkg/util/constants/constants.go

@@ -29,12 +29,13 @@ const (
 	PamConfiguration   = "https://info.example.com/oauth2/tokeninfo?access_token= uid realm=/employees"
 	PasswordLength     = 64
 	TeamsAPIUrl        = "https://teams.example.com/api/"
-	UserSecretTemplate = "%s.%s.credentials.%s.%s"
+	UserSecretTemplate = "%s.%s.credentials.%s.%s" // Username, ClusterName, TPRName, TPRVendor
 
 	OAuthTokenSecretName     = "postgresql-operator"
 	ServiceAccountName       = "operator"
 	DataVolumeName           = "pgdata"
 	ZalandoDnsNameAnnotation = "zalando.org/dnsname"
+
 	// TODO: move DbHostedZone to operator configuration
 	DbHostedZone = "db.example.com"
 )

pkg/util/k8sutil/tpr_util.go

@@ -15,7 +15,7 @@ func listClustersURI(ns string) string {
 }
 
 func WaitTPRReady(restclient rest.Interface, interval, timeout time.Duration, ns string) error {
-	return retryutil.Retry(interval, int(timeout/interval), func() (bool, error) {
+	return retryutil.Retry(interval, timeout, func() (bool, error) {
 		_, err := restclient.Get().RequestURI(listClustersURI(ns)).DoRaw()
 		if err != nil {
 			if ResourceNotFound(err) { // not set up yet. wait more.

pkg/util/retryutil/retry_util.go

@@ -5,24 +5,14 @@ import (
 	"time"
 )
 
-type RetryError struct {
-	n int
-}
-
-func (e *RetryError) Error() string {
-	return fmt.Sprintf("still failing after %d retries", e.n)
-}
-
 type ConditionFunc func() (bool, error)
 
-// Retry retries f every interval until after maxRetries.
-// The interval won't be affected by how long f takes.
-// For example, if interval is 3s, f takes 1s, another f will be called 2s later.
-// However, if f takes longer than interval, it will be delayed.
-func Retry(interval time.Duration, maxRetries int, f ConditionFunc) error {
-	if maxRetries <= 0 {
-		return fmt.Errorf("maxRetries (%d) should be > 0", maxRetries)
+func Retry(interval time.Duration, timeout time.Duration, f ConditionFunc) error {
+	//TODO: make the retry exponential
+	if timeout < interval {
+		return fmt.Errorf("timout(%s) should be greater than interval(%s)", timeout, interval)
 	}
+	maxRetries := int(timeout / interval)
 	tick := time.NewTicker(interval)
 	defer tick.Stop()
 
@@ -39,5 +29,5 @@ func Retry(interval time.Duration, maxRetries int, f ConditionFunc) error {
 		}
 		<-tick.C
 	}
-	return &RetryError{maxRetries}
+	return fmt.Errorf("Still failing after %d retries", maxRetries)
 }

pkg/util/util.go

@@ -45,6 +45,10 @@ func PodClusterName(pod *v1.Pod) spec.ClusterName {
 	return spec.ClusterName{}
 }
 
+func PodSpiloRole(pod *v1.Pod) string {
+	return pod.Labels["spilo-role"]
+}
+
 func ClusterDNSName(clusterName, teamName, hostedZone string) string {
 	return fmt.Sprintf("%s.%s.%s", clusterName, teamName, hostedZone)
 }