postgres-operator/pkg/cluster/sync.go

package cluster

import (
	"context"
	"encoding/json"
	"fmt"
	"reflect"
	"regexp"
	"strings"
	"time"

	acidv1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
	"github.com/zalando/postgres-operator/pkg/spec"
	"github.com/zalando/postgres-operator/pkg/util"
	"github.com/zalando/postgres-operator/pkg/util/constants"
	"github.com/zalando/postgres-operator/pkg/util/k8sutil"
	batchv1beta1 "k8s.io/api/batch/v1beta1"
	v1 "k8s.io/api/core/v1"
	policybeta1 "k8s.io/api/policy/v1beta1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

// Sync syncs the cluster, making sure the actual Kubernetes objects correspond to what is defined in the manifest.
// Unlike the update, sync does not error out if some objects do not exist and takes care of creating them.
func (c *Cluster) Sync(newSpec *acidv1.Postgresql) error {
	var err error
	c.mu.Lock()
	defer c.mu.Unlock()

	oldSpec := c.Postgresql
	c.setSpec(newSpec)

	defer func() {
		if err != nil {
			c.logger.Warningf("error while syncing cluster state: %v", err)
			c.KubeClient.SetPostgresCRDStatus(c.clusterName(), acidv1.ClusterStatusSyncFailed)
		} else if !c.Status.Running() {
			c.KubeClient.SetPostgresCRDStatus(c.clusterName(), acidv1.ClusterStatusRunning)
		}
	}()

	if err = c.initUsers(); err != nil {
		err = fmt.Errorf("could not init users: %v", err)
		return err
	}

	//TODO: mind the secrets of the deleted/new users
	if err = c.syncSecrets(); err != nil {
		err = fmt.Errorf("could not sync secrets: %v", err)
		return err
	}

	if err = c.syncServices(); err != nil {
		err = fmt.Errorf("could not sync services: %v", err)
		return err
	}

	// sync volume may already transition volumes to gp3, if iops/throughput or type is specified
	if err = c.syncVolumes(); err != nil {
		return err
	}

	if c.OpConfig.EnableEBSGp3Migration {
		err = c.executeEBSMigration()
		if nil != err {
			return err
		}
	}

	if err = c.enforceMinResourceLimits(&c.Spec); err != nil {
		err = fmt.Errorf("could not enforce minimum resource limits: %v", err)
		return err
	}

	c.logger.Debug("syncing statefulsets")
	if err = c.syncStatefulSet(); err != nil {
		if !k8sutil.ResourceAlreadyExists(err) {
			err = fmt.Errorf("could not sync statefulsets: %v", err)
			return err
		}
	}

	c.logger.Debug("syncing pod disruption budgets")
	if err = c.syncPodDisruptionBudget(false); err != nil {
		err = fmt.Errorf("could not sync pod disruption budget: %v", err)
		return err
	}

	// create a logical backup job unless we are running without pods or disable that feature explicitly
	if c.Spec.EnableLogicalBackup && c.getNumberOfInstances(&c.Spec) > 0 {

		c.logger.Debug("syncing logical backup job")
		if err = c.syncLogicalBackupJob(); err != nil {
			err = fmt.Errorf("could not sync the logical backup job: %v", err)
			return err
		}
	}

	// create database objects unless we are running without pods or disabled that feature explicitly
	if !(c.databaseAccessDisabled() || c.getNumberOfInstances(&newSpec.Spec) <= 0 || c.Spec.StandbyCluster != nil) {
		c.logger.Debug("syncing roles")
		if err = c.syncRoles(); err != nil {
			err = fmt.Errorf("could not sync roles: %v", err)
			return err
		}
		c.logger.Debug("syncing databases")
		if err = c.syncDatabases(); err != nil {
			err = fmt.Errorf("could not sync databases: %v", err)
			return err
		}
		c.logger.Debug("syncing prepared databases with schemas")
		if err = c.syncPreparedDatabases(); err != nil {
			err = fmt.Errorf("could not sync prepared database: %v", err)
			return err
		}
	}

	// sync connection pooler
	if _, err = c.syncConnectionPooler(&oldSpec, newSpec, c.installLookupFunction); err != nil {
		return fmt.Errorf("could not sync connection pooler: %v", err)
	}

	c.logger.Debug("syncing streams")
	if err = c.syncStreams(); err != nil {
		err = fmt.Errorf("could not sync streams: %v", err)
		return err
	}

	// Major version upgrade must only run after success of all earlier operations, must remain last item in sync
	if err := c.majorVersionUpgrade(); err != nil {
		c.logger.Errorf("major version upgrade failed: %v", err)
	}

	return err
}

func (c *Cluster) syncServices() error {
	for _, role := range []PostgresRole{Master, Replica} {
		c.logger.Debugf("syncing %s service", role)

		if !c.patroniKubernetesUseConfigMaps() {
			if err := c.syncEndpoint(role); err != nil {
				return fmt.Errorf("could not sync %s endpoint: %v", role, err)
			}
		}
		if err := c.syncService(role); err != nil {
			return fmt.Errorf("could not sync %s service: %v", role, err)
		}
	}

	return nil
}

func (c *Cluster) syncService(role PostgresRole) error {
	var (
		svc *v1.Service
		err error
	)
	c.setProcessName("syncing %s service", role)

	if svc, err = c.KubeClient.Services(c.Namespace).Get(context.TODO(), c.serviceName(role), metav1.GetOptions{}); err == nil {
		c.Services[role] = svc
		desiredSvc := c.generateService(role, &c.Spec)
		if match, reason := k8sutil.SameService(svc, desiredSvc); !match {
			c.logServiceChanges(role, svc, desiredSvc, false, reason)
			if err = c.updateService(role, desiredSvc); err != nil {
				return fmt.Errorf("could not update %s service to match desired state: %v", role, err)
			}
			c.logger.Infof("%s service %q is in the desired state now", role, util.NameFromMeta(desiredSvc.ObjectMeta))
		}
		return nil
	}
	if !k8sutil.ResourceNotFound(err) {
		return fmt.Errorf("could not get %s service: %v", role, err)
	}
	// no existing service, create new one
	c.Services[role] = nil
	c.logger.Infof("could not find the cluster's %s service", role)

	if svc, err = c.createService(role); err == nil {
		c.logger.Infof("created missing %s service %q", role, util.NameFromMeta(svc.ObjectMeta))
	} else {
		if !k8sutil.ResourceAlreadyExists(err) {
			return fmt.Errorf("could not create missing %s service: %v", role, err)
		}
		c.logger.Infof("%s service %q already exists", role, util.NameFromMeta(svc.ObjectMeta))
		if svc, err = c.KubeClient.Services(c.Namespace).Get(context.TODO(), c.serviceName(role), metav1.GetOptions{}); err != nil {
			return fmt.Errorf("could not fetch existing %s service: %v", role, err)
		}
	}
	c.Services[role] = svc
	return nil
}

func (c *Cluster) syncEndpoint(role PostgresRole) error {
	var (
		ep  *v1.Endpoints
		err error
	)
	c.setProcessName("syncing %s endpoint", role)

	if ep, err = c.KubeClient.Endpoints(c.Namespace).Get(context.TODO(), c.endpointName(role), metav1.GetOptions{}); err == nil {
		// TODO: No syncing of endpoints here, is this covered completely by updateService?
		c.Endpoints[role] = ep
		return nil
	}
	if !k8sutil.ResourceNotFound(err) {
		return fmt.Errorf("could not get %s endpoint: %v", role, err)
	}
	// no existing endpoint, create new one
	c.Endpoints[role] = nil
	c.logger.Infof("could not find the cluster's %s endpoint", role)

	if ep, err = c.createEndpoint(role); err == nil {
		c.logger.Infof("created missing %s endpoint %q", role, util.NameFromMeta(ep.ObjectMeta))
	} else {
		if !k8sutil.ResourceAlreadyExists(err) {
			return fmt.Errorf("could not create missing %s endpoint: %v", role, err)
		}
		c.logger.Infof("%s endpoint %q already exists", role, util.NameFromMeta(ep.ObjectMeta))
		if ep, err = c.KubeClient.Endpoints(c.Namespace).Get(context.TODO(), c.endpointName(role), metav1.GetOptions{}); err != nil {
			return fmt.Errorf("could not fetch existing %s endpoint: %v", role, err)
		}
	}
	c.Endpoints[role] = ep
	return nil
}

func (c *Cluster) syncPodDisruptionBudget(isUpdate bool) error {
	var (
		pdb *policybeta1.PodDisruptionBudget
		err error
	)
	if pdb, err = c.KubeClient.PodDisruptionBudgets(c.Namespace).Get(context.TODO(), c.podDisruptionBudgetName(), metav1.GetOptions{}); err == nil {
		c.PodDisruptionBudget = pdb
		newPDB := c.generatePodDisruptionBudget()
		if match, reason := k8sutil.SamePDB(pdb, newPDB); !match {
			c.logPDBChanges(pdb, newPDB, isUpdate, reason)
			if err = c.updatePodDisruptionBudget(newPDB); err != nil {
				return err
			}
		} else {
			c.PodDisruptionBudget = pdb
		}
		return nil

	}
	if !k8sutil.ResourceNotFound(err) {
		return fmt.Errorf("could not get pod disruption budget: %v", err)
	}
	// no existing pod disruption budget, create new one
	c.PodDisruptionBudget = nil
	c.logger.Infof("could not find the cluster's pod disruption budget")

	if pdb, err = c.createPodDisruptionBudget(); err != nil {
		if !k8sutil.ResourceAlreadyExists(err) {
			return fmt.Errorf("could not create pod disruption budget: %v", err)
		}
		c.logger.Infof("pod disruption budget %q already exists", util.NameFromMeta(pdb.ObjectMeta))
		if pdb, err = c.KubeClient.PodDisruptionBudgets(c.Namespace).Get(context.TODO(), c.podDisruptionBudgetName(), metav1.GetOptions{}); err != nil {
			return fmt.Errorf("could not fetch existing %q pod disruption budget", util.NameFromMeta(pdb.ObjectMeta))
		}
	}

	c.logger.Infof("created missing pod disruption budget %q", util.NameFromMeta(pdb.ObjectMeta))
	c.PodDisruptionBudget = pdb

	return nil
}

func (c *Cluster) syncStatefulSet() error {
	var (
		masterPod               *v1.Pod
		effectivePostgresConfig map[string]interface{}
		instanceRestartRequired bool
	)

	desiredPostgresConfig := make(map[string]interface{})
	podsToRecreate := make([]v1.Pod, 0)
	switchoverCandidates := make([]spec.NamespacedName, 0)

	pods, err := c.listPods()
	if err != nil {
		c.logger.Warnf("could not list pods of the statefulset: %v", err)
	}

	// NB: Be careful to consider the codepath that acts on podsRollingUpdateRequired before returning early.
	sset, err := c.KubeClient.StatefulSets(c.Namespace).Get(context.TODO(), c.statefulSetName(), metav1.GetOptions{})
	if err != nil {
		if !k8sutil.ResourceNotFound(err) {
			return fmt.Errorf("error during reading of statefulset: %v", err)
		}
		// statefulset does not exist, try to re-create it
		c.Statefulset = nil
		c.logger.Infof("cluster's statefulset does not exist")

		sset, err = c.createStatefulSet()
		if err != nil {
			return fmt.Errorf("could not create missing statefulset: %v", err)
		}

		if err = c.waitStatefulsetPodsReady(); err != nil {
			return fmt.Errorf("cluster is not ready: %v", err)
		}

		if len(pods) > 0 {
			for _, pod := range pods {
				if err = c.markRollingUpdateFlagForPod(&pod, "pod from previous statefulset"); err != nil {
					c.logger.Warnf("marking old pod for rolling update failed: %v", err)
				}
				podsToRecreate = append(podsToRecreate, pod)
			}
		}
		c.logger.Infof("created missing statefulset %q", util.NameFromMeta(sset.ObjectMeta))

	} else {
		// check if there are still pods with a rolling update flag
		for _, pod := range pods {
			if c.getRollingUpdateFlagFromPod(&pod) {
				podsToRecreate = append(podsToRecreate, pod)
			} else {
				role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])
				if role == Master {
					continue
				}
				switchoverCandidates = append(switchoverCandidates, util.NameFromMeta(pod.ObjectMeta))
			}
		}

		if len(podsToRecreate) > 0 {
			c.logger.Debugf("%d / %d pod(s) still need to be rotated", len(podsToRecreate), len(pods))
		}

		// statefulset is already there, make sure we use its definition in order to compare with the spec.
		c.Statefulset = sset

		desiredSts, err := c.generateStatefulSet(&c.Spec)
		if err != nil {
			return fmt.Errorf("could not generate statefulset: %v", err)
		}

		cmp := c.compareStatefulSetWith(desiredSts)
		if !cmp.match {
			if cmp.rollingUpdate {
				podsToRecreate = make([]v1.Pod, 0)
				switchoverCandidates = make([]spec.NamespacedName, 0)
				for _, pod := range pods {
					if err = c.markRollingUpdateFlagForPod(&pod, "pod changes"); err != nil {
						return fmt.Errorf("updating rolling update flag for pod failed: %v", err)
					}
					podsToRecreate = append(podsToRecreate, pod)
				}
			}

			c.logStatefulSetChanges(c.Statefulset, desiredSts, false, cmp.reasons)

			if !cmp.replace {
				if err := c.updateStatefulSet(desiredSts); err != nil {
					return fmt.Errorf("could not update statefulset: %v", err)
				}
			} else {
				if err := c.replaceStatefulSet(desiredSts); err != nil {
					return fmt.Errorf("could not replace statefulset: %v", err)
				}
			}
		}

		if len(podsToRecreate) == 0 && !c.OpConfig.EnableLazySpiloUpgrade {
			// even if the desired and the running statefulsets match
			// there still may be not up-to-date pods on condition
			//  (a) the lazy update was just disabled
			// and
			//  (b) some of the pods were not restarted when the lazy update was still in place
			for _, pod := range pods {
				effectivePodImage := getPostgresContainer(&pod.Spec).Image
				stsImage := getPostgresContainer(&desiredSts.Spec.Template.Spec).Image

				if stsImage != effectivePodImage {
					if err = c.markRollingUpdateFlagForPod(&pod, "pod not yet restarted due to lazy update"); err != nil {
						c.logger.Warnf("updating rolling update flag failed for pod %q: %v", pod.Name, err)
					}
					podsToRecreate = append(podsToRecreate, pod)
				} else {
					role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])
					if role == Master {
						continue
					}
					switchoverCandidates = append(switchoverCandidates, util.NameFromMeta(pod.ObjectMeta))
				}
			}
		}
	}

	// Apply special PostgreSQL parameters that can only be set via the Patroni API.
	// it is important to do it after the statefulset pods are there, but before the rolling update
	// since those parameters require PostgreSQL restart.
	pods, err = c.listPods()
	if err != nil {
		c.logger.Warnf("could not get list of pods to apply special PostgreSQL parameters only to be set via Patroni API: %v", err)
	}

	// get Postgres config, compare with manifest and update via Patroni PATCH endpoint if it differs
	// Patroni's config endpoint is just a "proxy" to DCS. It is enough to patch it only once and it doesn't matter which pod is used.
	if len(c.Spec.Parameters) > 0 {
		desiredPostgresConfig["postgresql"] = map[string]interface{}{patroniPGParametersParameterName: c.Spec.Parameters}
	}
	if c.Spec.Patroni.LoopWait > 0 {
		desiredPostgresConfig["loop_wait"] = c.Spec.Patroni.LoopWait
	}
	if c.Spec.Patroni.MaximumLagOnFailover > 0 {
		desiredPostgresConfig["maximum_lag_on_failover"] = c.Spec.Patroni.MaximumLagOnFailover
	}
	if c.Spec.Patroni.PgHba != nil {
		desiredPostgresConfig["pg_hba"] = c.Spec.Patroni.PgHba
	}
	if c.Spec.Patroni.RetryTimeout > 0 {
		desiredPostgresConfig["retry_timeout"] = c.Spec.Patroni.RetryTimeout
	}
	if c.Spec.Patroni.Slots != nil {
		desiredPostgresConfig["slots"] = c.Spec.Patroni.Slots
	}
	if c.Spec.Patroni.TTL > 0 {
		desiredPostgresConfig["ttl"] = c.Spec.Patroni.TTL
	}
	if effectivePostgresConfig["synchronous_mode"] != c.Spec.Patroni.SynchronousMode {
		desiredPostgresConfig["synchronous_mode"] = c.Spec.Patroni.SynchronousMode
	}
	if effectivePostgresConfig["synchronous_mode_strict"] != c.Spec.Patroni.SynchronousModeStrict {
		desiredPostgresConfig["synchronous_mode_strict"] = c.Spec.Patroni.SynchronousModeStrict
	}

	for i, pod := range pods {
		podName := util.NameFromMeta(pods[i].ObjectMeta)
		effectivePostgresConfig, err := c.patroni.GetConfig(&pod)
		if err != nil {
			c.logger.Warningf("could not get Postgres config from pod %s: %v", podName, err)
			continue
		}

		instanceRestartRequired, err = c.checkAndSetGlobalPostgreSQLConfiguration(&pod, effectivePostgresConfig, desiredPostgresConfig)
		if err != nil {
			c.logger.Warningf("could not set PostgreSQL configuration options for pod %s: %v", podName, err)
			continue
		}
		break
	}

	// if the config update requires a restart, call Patroni restart for replicas first, then master
	if instanceRestartRequired {
		c.logger.Debug("restarting Postgres server within pods")
		ttl, ok := effectivePostgresConfig["ttl"].(int32)
		if !ok {
			ttl = 30
		}
		for i, pod := range pods {
			role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])
			if role == Master {
				masterPod = &pods[i]
				continue
			}
			c.restartInstance(&pod)
			time.Sleep(time.Duration(ttl) * time.Second)
		}

		if masterPod != nil {
			c.restartInstance(masterPod)
		}
	}

	// if we get here we also need to re-create the pods (either leftovers from the old
	// statefulset or those that got their configuration from the outdated statefulset)
	if len(podsToRecreate) > 0 {
		c.logger.Debugln("performing rolling update")
		c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", "Performing rolling update")
		if err := c.recreatePods(podsToRecreate, switchoverCandidates); err != nil {
			return fmt.Errorf("could not recreate pods: %v", err)
		}
		c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", "Rolling update done - pods have been recreated")
	}
	return nil
}

func (c *Cluster) restartInstance(pod *v1.Pod) {
	podName := util.NameFromMeta(pod.ObjectMeta)
	role := PostgresRole(pod.Labels[c.OpConfig.PodRoleLabel])

	c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", fmt.Sprintf("restarting Postgres server within %s pod %s", role, pod.Name))

	if err := c.patroni.Restart(pod); err != nil {
		c.logger.Warningf("could not restart Postgres server within %s pod %s: %v", role, podName, err)
		return
	}

	c.logger.Debugf("Postgres server successfuly restarted in %s pod %s", role, podName)
	c.eventRecorder.Event(c.GetReference(), v1.EventTypeNormal, "Update", fmt.Sprintf("Postgres server restart done for %s pod %s", role, pod.Name))
}

// AnnotationsToPropagate get the annotations to update if required
// based on the annotations in postgres CRD
func (c *Cluster) AnnotationsToPropagate(annotations map[string]string) map[string]string {

	if annotations == nil {
		annotations = make(map[string]string)
	}

	pgCRDAnnotations := c.ObjectMeta.Annotations

	if pgCRDAnnotations != nil {
		for _, anno := range c.OpConfig.DownscalerAnnotations {
			for k, v := range pgCRDAnnotations {
				matched, err := regexp.MatchString(anno, k)
				if err != nil {
					c.logger.Errorf("annotations matching issue: %v", err)
					return nil
				}
				if matched {
					annotations[k] = v
				}
			}
		}
	}

	if len(annotations) > 0 {
		return annotations
	}

	return nil
}

// checkAndSetGlobalPostgreSQLConfiguration checks whether cluster-wide API parameters
// (like max_connections) have changed and if necessary sets it via the Patroni API
func (c *Cluster) checkAndSetGlobalPostgreSQLConfiguration(pod *v1.Pod, effectivePostgresConfig, desiredPostgresConfig map[string]interface{}) (bool, error) {

	configUpdateRequired := false
	for parameter, value := range desiredPostgresConfig {
		if !reflect.DeepEqual(effectivePostgresConfig[parameter], value) {
			configUpdateRequired = true
			break
		}
	}
	if !configUpdateRequired {
		return false, nil
	}

	configToSetJson, err := json.Marshal(desiredPostgresConfig)
	if err != nil {
		c.logger.Debugf("could not convert config patch to JSON: %v", err)
	}

	// try all pods until the first one that is successful, as it doesn't matter which pod
	// carries the request to change configuration through
	podName := util.NameFromMeta(pod.ObjectMeta)
	c.logger.Debugf("patching Postgres config via Patroni API on pod %s with following options: %s",
		podName, configToSetJson)
	if err = c.patroni.SetConfig(pod, desiredPostgresConfig); err != nil {
		return true, fmt.Errorf("could not patch postgres parameters within pod %s: %v", podName, err)
	}

	return true, nil
}

func (c *Cluster) syncSecrets() error {
	var (
		err    error
		secret *v1.Secret
	)
	c.logger.Info("syncing secrets")
	c.setProcessName("syncing secrets")
	secrets := c.generateUserSecrets()

	for secretUsername, secretSpec := range secrets {
		if secret, err = c.KubeClient.Secrets(secretSpec.Namespace).Create(context.TODO(), secretSpec, metav1.CreateOptions{}); err == nil {
			c.Secrets[secret.UID] = secret
			c.logger.Debugf("created new secret %s, namespace: %s, uid: %s", util.NameFromMeta(secret.ObjectMeta), secretSpec.Namespace, secret.UID)
			continue
		}
		if k8sutil.ResourceAlreadyExists(err) {
			var userMap map[string]spec.PgUser
			if secret, err = c.KubeClient.Secrets(secretSpec.Namespace).Get(context.TODO(), secretSpec.Name, metav1.GetOptions{}); err != nil {
				return fmt.Errorf("could not get current secret: %v", err)
			}
			if secretUsername != string(secret.Data["username"]) {
				c.logger.Errorf("secret %s does not contain the role %s", secretSpec.Name, secretUsername)
				continue
			}
			c.Secrets[secret.UID] = secret
			c.logger.Debugf("secret %s already exists, fetching its password", util.NameFromMeta(secret.ObjectMeta))
			if secretUsername == c.systemUsers[constants.SuperuserKeyName].Name {
				secretUsername = constants.SuperuserKeyName
				userMap = c.systemUsers
			} else if secretUsername == c.systemUsers[constants.ReplicationUserKeyName].Name {
				secretUsername = constants.ReplicationUserKeyName
				userMap = c.systemUsers
			} else {
				userMap = c.pgUsers
			}
			pwdUser := userMap[secretUsername]
			// if this secret belongs to the infrastructure role and the password has changed - replace it in the secret
			if pwdUser.Password != string(secret.Data["password"]) &&
				pwdUser.Origin == spec.RoleOriginInfrastructure {

				c.logger.Debugf("updating the secret %s from the infrastructure roles", secretSpec.Name)
				if _, err = c.KubeClient.Secrets(secretSpec.Namespace).Update(context.TODO(), secretSpec, metav1.UpdateOptions{}); err != nil {
					return fmt.Errorf("could not update infrastructure role secret for role %q: %v", secretUsername, err)
				}
			} else {
				// for non-infrastructure role - update the role with the password from the secret
				pwdUser.Password = string(secret.Data["password"])
				userMap[secretUsername] = pwdUser
			}
		} else {
			return fmt.Errorf("could not create secret for user %s: in namespace %s: %v", secretUsername, secretSpec.Namespace, err)
		}
	}

	return nil
}

func (c *Cluster) syncRoles() (err error) {
	c.setProcessName("syncing roles")

	var (
		dbUsers   spec.PgUserMap
		userNames []string
	)

	err = c.initDbConn()
	if err != nil {
		return fmt.Errorf("could not init db connection: %v", err)
	}

	defer func() {
		if err2 := c.closeDbConn(); err2 != nil {
			if err == nil {
				err = fmt.Errorf("could not close database connection: %v", err2)
			} else {
				err = fmt.Errorf("could not close database connection: %v (prior error: %v)", err2, err)
			}
		}
	}()

	// mapping between original role name and with deletion suffix
	deletedUsers := map[string]string{}

	// create list of database roles to query
	for _, u := range c.pgUsers {
		pgRole := u.Name
		userNames = append(userNames, pgRole)
		// add team member role name with rename suffix in case we need to rename it back
		if u.Origin == spec.RoleOriginTeamsAPI && c.OpConfig.EnableTeamMemberDeprecation {
			deletedUsers[pgRole+c.OpConfig.RoleDeletionSuffix] = pgRole
			userNames = append(userNames, pgRole+c.OpConfig.RoleDeletionSuffix)
		}
	}

	// add team members that exist only in cache
	// to trigger a rename of the role in ProduceSyncRequests
	for _, cachedUser := range c.pgUsersCache {
		if _, exists := c.pgUsers[cachedUser.Name]; !exists {
			userNames = append(userNames, cachedUser.Name)
		}
	}

	// add pooler user to list of pgUsers, too
	// to check if the pooler user exists or has to be created
	if needMasterConnectionPooler(&c.Spec) || needReplicaConnectionPooler(&c.Spec) {
		connectionPoolerUser := c.systemUsers[constants.ConnectionPoolerUserKeyName]
		userNames = append(userNames, connectionPoolerUser.Name)

		if _, exists := c.pgUsers[connectionPoolerUser.Name]; !exists {
			c.pgUsers[connectionPoolerUser.Name] = connectionPoolerUser
		}
	}

	dbUsers, err = c.readPgUsersFromDatabase(userNames)
	if err != nil {
		return fmt.Errorf("error getting users from the database: %v", err)
	}

	// update pgUsers where a deleted role was found
	// so that they are skipped in ProduceSyncRequests
	for _, dbUser := range dbUsers {
		if originalUser, exists := deletedUsers[dbUser.Name]; exists {
			recreatedUser := c.pgUsers[originalUser]
			recreatedUser.Deleted = true
			c.pgUsers[originalUser] = recreatedUser
		}
	}

	pgSyncRequests := c.userSyncStrategy.ProduceSyncRequests(dbUsers, c.pgUsers)
	if err = c.userSyncStrategy.ExecuteSyncRequests(pgSyncRequests, c.pgDb); err != nil {
		return fmt.Errorf("error executing sync statements: %v", err)
	}

	return nil
}

func (c *Cluster) syncDatabases() error {
	c.setProcessName("syncing databases")

	createDatabases := make(map[string]string)
	alterOwnerDatabases := make(map[string]string)
	preparedDatabases := make([]string, 0)

	if err := c.initDbConn(); err != nil {
		return fmt.Errorf("could not init database connection")
	}
	defer func() {
		if err := c.closeDbConn(); err != nil {
			c.logger.Errorf("could not close database connection: %v", err)
		}
	}()

	currentDatabases, err := c.getDatabases()
	if err != nil {
		return fmt.Errorf("could not get current databases: %v", err)
	}

	// if no prepared databases are specified create a database named like the cluster
	if c.Spec.PreparedDatabases != nil && len(c.Spec.PreparedDatabases) == 0 { // TODO: add option to disable creating such a default DB
		c.Spec.PreparedDatabases = map[string]acidv1.PreparedDatabase{strings.Replace(c.Name, "-", "_", -1): {}}
	}
	for preparedDatabaseName := range c.Spec.PreparedDatabases {
		_, exists := currentDatabases[preparedDatabaseName]
		if !exists {
			createDatabases[preparedDatabaseName] = preparedDatabaseName + constants.OwnerRoleNameSuffix
			preparedDatabases = append(preparedDatabases, preparedDatabaseName)
		}
	}

	for databaseName, newOwner := range c.Spec.Databases {
		currentOwner, exists := currentDatabases[databaseName]
		if !exists {
			createDatabases[databaseName] = newOwner
		} else if currentOwner != newOwner {
			alterOwnerDatabases[databaseName] = newOwner
		}
	}

	if len(createDatabases)+len(alterOwnerDatabases) == 0 {
		return nil
	}

	for databaseName, owner := range createDatabases {
		if err = c.executeCreateDatabase(databaseName, owner); err != nil {
			return err
		}
	}
	for databaseName, owner := range alterOwnerDatabases {
		if err = c.executeAlterDatabaseOwner(databaseName, owner); err != nil {
			return err
		}
	}

	if len(createDatabases) > 0 {
		// trigger creation of pooler objects in new database in syncConnectionPooler
		if c.ConnectionPooler != nil {
			for _, role := range [2]PostgresRole{Master, Replica} {
				c.ConnectionPooler[role].LookupFunction = false
			}
		}
	}

	// set default privileges for prepared database
	for _, preparedDatabase := range preparedDatabases {
		if err := c.initDbConnWithName(preparedDatabase); err != nil {
			return fmt.Errorf("could not init database connection to %s", preparedDatabase)
		}

		for _, owner := range c.getOwnerRoles(preparedDatabase, c.Spec.PreparedDatabases[preparedDatabase].DefaultUsers) {
			if err = c.execAlterGlobalDefaultPrivileges(owner, preparedDatabase); err != nil {
				return err
			}
		}
	}

	return nil
}

func (c *Cluster) syncPreparedDatabases() error {
	c.setProcessName("syncing prepared databases")
	for preparedDbName, preparedDB := range c.Spec.PreparedDatabases {
		if err := c.initDbConnWithName(preparedDbName); err != nil {
			return fmt.Errorf("could not init connection to database %s: %v", preparedDbName, err)
		}

		c.logger.Debugf("syncing prepared database %q", preparedDbName)
		// now, prepare defined schemas
		preparedSchemas := preparedDB.PreparedSchemas
		if len(preparedDB.PreparedSchemas) == 0 {
			preparedSchemas = map[string]acidv1.PreparedSchema{"data": {DefaultRoles: util.True()}}
		}
		if err := c.syncPreparedSchemas(preparedDbName, preparedSchemas); err != nil {
			return err
		}

		// install extensions
		if err := c.syncExtensions(preparedDB.Extensions); err != nil {
			return err
		}

		if err := c.closeDbConn(); err != nil {
			c.logger.Errorf("could not close database connection: %v", err)
		}
	}

	return nil
}

func (c *Cluster) syncPreparedSchemas(databaseName string, preparedSchemas map[string]acidv1.PreparedSchema) error {
	c.setProcessName("syncing prepared schemas")

	currentSchemas, err := c.getSchemas()
	if err != nil {
		return fmt.Errorf("could not get current schemas: %v", err)
	}

	var schemas []string

	for schema := range preparedSchemas {
		schemas = append(schemas, schema)
	}

	if createPreparedSchemas, equal := util.SubstractStringSlices(schemas, currentSchemas); !equal {
		for _, schemaName := range createPreparedSchemas {
			owner := constants.OwnerRoleNameSuffix
			dbOwner := databaseName + owner
			if preparedSchemas[schemaName].DefaultRoles == nil || *preparedSchemas[schemaName].DefaultRoles {
				owner = databaseName + "_" + schemaName + owner
			} else {
				owner = dbOwner
			}
			if err = c.executeCreateDatabaseSchema(databaseName, schemaName, dbOwner, owner); err != nil {
				return err
			}
		}
	}

	return nil
}

func (c *Cluster) syncExtensions(extensions map[string]string) error {
	c.setProcessName("syncing database extensions")

	createExtensions := make(map[string]string)
	alterExtensions := make(map[string]string)

	currentExtensions, err := c.getExtensions()
	if err != nil {
		return fmt.Errorf("could not get current database extensions: %v", err)
	}

	for extName, newSchema := range extensions {
		currentSchema, exists := currentExtensions[extName]
		if !exists {
			createExtensions[extName] = newSchema
		} else if currentSchema != newSchema {
			alterExtensions[extName] = newSchema
		}
	}

	for extName, schema := range createExtensions {
		if err = c.executeCreateExtension(extName, schema); err != nil {
			return err
		}
	}
	for extName, schema := range alterExtensions {
		if err = c.executeAlterExtension(extName, schema); err != nil {
			return err
		}
	}

	return nil
}

func (c *Cluster) syncLogicalBackupJob() error {
	var (
		job        *batchv1beta1.CronJob
		desiredJob *batchv1beta1.CronJob
		err        error
	)
	c.setProcessName("syncing the logical backup job")

	// sync the job if it exists

	jobName := c.getLogicalBackupJobName()
	if job, err = c.KubeClient.CronJobsGetter.CronJobs(c.Namespace).Get(context.TODO(), jobName, metav1.GetOptions{}); err == nil {

		desiredJob, err = c.generateLogicalBackupJob()
		if err != nil {
			return fmt.Errorf("could not generate the desired logical backup job state: %v", err)
		}
		if match, reason := k8sutil.SameLogicalBackupJob(job, desiredJob); !match {
			c.logger.Infof("logical job %s is not in the desired state and needs to be updated",
				c.getLogicalBackupJobName(),
			)
			if reason != "" {
				c.logger.Infof("reason: %s", reason)
			}
			if err = c.patchLogicalBackupJob(desiredJob); err != nil {
				return fmt.Errorf("could not update logical backup job to match desired state: %v", err)
			}
			c.logger.Info("the logical backup job is synced")
		}
		return nil
	}
	if !k8sutil.ResourceNotFound(err) {
		return fmt.Errorf("could not get logical backp job: %v", err)
	}

	// no existing logical backup job, create new one
	c.logger.Info("could not find the cluster's logical backup job")

	if err = c.createLogicalBackupJob(); err == nil {
		c.logger.Infof("created missing logical backup job %s", jobName)
	} else {
		if !k8sutil.ResourceAlreadyExists(err) {
			return fmt.Errorf("could not create missing logical backup job: %v", err)
		}
		c.logger.Infof("logical backup job %s already exists", jobName)
		if _, err = c.KubeClient.CronJobsGetter.CronJobs(c.Namespace).Get(context.TODO(), jobName, metav1.GetOptions{}); err != nil {
			return fmt.Errorf("could not fetch existing logical backup job: %v", err)
		}
	}

	return nil
}