Linter-induced code refactoring, run round 2. (#360)

Run more linters in the gometalinter, i.e. deadcode, megacheck,
nakedret, dup.

More consistent code formatting, remove two dead functions, eliminate
naked a bunch of naked returns, refactor a few functions to avoid code
duplication.

pkg/apiserver/apiserver.go

@@ -157,7 +157,7 @@ func (s *Server) clusters(w http.ResponseWriter, req *http.Request) {
 	)
 
 	if matches := util.FindNamedStringSubmatch(clusterStatusURL, req.URL.Path); matches != nil {
-		namespace, _ := matches["namespace"]
+		namespace := matches["namespace"]
 		resp, err = s.controller.ClusterStatus(matches["team"], namespace, matches["cluster"])
 	} else if matches := util.FindNamedStringSubmatch(teamURL, req.URL.Path); matches != nil {
 		teamClusters := s.controller.TeamClusterList()
@@ -174,10 +174,10 @@ func (s *Server) clusters(w http.ResponseWriter, req *http.Request) {
 
 		resp, err = clusterNames, nil
 	} else if matches := util.FindNamedStringSubmatch(clusterLogsURL, req.URL.Path); matches != nil {
-		namespace, _ := matches["namespace"]
+		namespace := matches["namespace"]
 		resp, err = s.controller.ClusterLogs(matches["team"], namespace, matches["cluster"])
 	} else if matches := util.FindNamedStringSubmatch(clusterHistoryURL, req.URL.Path); matches != nil {
-		namespace, _ := matches["namespace"]
+		namespace := matches["namespace"]
 		resp, err = s.controller.ClusterHistory(matches["team"], namespace, matches["cluster"])
 	} else if req.URL.Path == clustersURL {
 		clusterNamesPerTeam := make(map[string][]string)
@@ -194,8 +194,8 @@ func (s *Server) clusters(w http.ResponseWriter, req *http.Request) {
 	s.respond(resp, err, w)
 }
 
-func mustConvertToUint32(s string) uint32{
+func mustConvertToUint32(s string) uint32 {
-	result, err := strconv.Atoi(s);
+	result, err := strconv.Atoi(s)
 	if err != nil {
 		panic(fmt.Errorf("mustConvertToUint32 called for %s: %v", s, err))
 	}
@@ -244,8 +244,6 @@ func (s *Server) databases(w http.ResponseWriter, req *http.Request) {
 
 	databaseNamesPerCluster := s.controller.ClusterDatabasesMap()
 	s.respond(databaseNamesPerCluster, nil, w)
-	return
-
 }
 
 func (s *Server) allQueues(w http.ResponseWriter, r *http.Request) {

pkg/cluster/cluster.go

@@ -450,8 +450,8 @@ func (c *Cluster) compareContainers(setA, setB *v1beta1.StatefulSet) (bool, []st
 	return needsRollUpdate, reasons
 }
 
-func compareResources(a *v1.ResourceRequirements, b *v1.ResourceRequirements) (equal bool) {
+func compareResources(a *v1.ResourceRequirements, b *v1.ResourceRequirements) bool {
-	equal = true
+	equal := true
 	if a != nil {
 		equal = compareResoucesAssumeFirstNotNil(a, b)
 	}
@@ -459,7 +459,7 @@ func compareResources(a *v1.ResourceRequirements, b *v1.ResourceRequirements) (e
 		equal = compareResoucesAssumeFirstNotNil(b, a)
 	}
 
-	return
+	return equal
 }
 
 func compareResoucesAssumeFirstNotNil(a *v1.ResourceRequirements, b *v1.ResourceRequirements) bool {
@@ -786,7 +786,8 @@ func (c *Cluster) initInfrastructureRoles() error {
 }
 
 // resolves naming conflicts between existing and new roles by chosing either of them.
-func (c *Cluster) resolveNameConflict(currentRole, newRole *spec.PgUser) (result spec.PgUser) {
+func (c *Cluster) resolveNameConflict(currentRole, newRole *spec.PgUser) spec.PgUser {
+	var result spec.PgUser
 	if newRole.Origin >= currentRole.Origin {
 		result = *newRole
 	} else {
@@ -794,7 +795,7 @@ func (c *Cluster) resolveNameConflict(currentRole, newRole *spec.PgUser) (result
 	}
 	c.logger.Debugf("resolved a conflict of role %q between %s and %s to %s",
 		newRole.Name, newRole.Origin, currentRole.Origin, result.Origin)
-	return
+	return result
 }
 
 func (c *Cluster) shouldAvoidProtectedOrSystemRole(username, purpose string) bool {
@@ -838,8 +839,9 @@ func (c *Cluster) GetStatus() *spec.ClusterStatus {
 }
 
 // Switchover does a switchover (via Patroni) to a candidate pod
-func (c *Cluster) Switchover(curMaster *v1.Pod, candidate spec.NamespacedName) (err error) {
+func (c *Cluster) Switchover(curMaster *v1.Pod, candidate spec.NamespacedName) error {
 
+	var err error
 	c.logger.Debugf("failing over from %q to %q", curMaster.Name, candidate)
 
 	var wg sync.WaitGroup
@@ -858,8 +860,8 @@ func (c *Cluster) Switchover(curMaster *v1.Pod, candidate spec.NamespacedName) (
 
 		select {
 		case <-stopCh:
-		case podLabelErr <- func() (err error) {
+		case podLabelErr <- func() (err2 error) {
-			_, err = c.waitForPodLabel(ch, stopCh, &role)
+			_, err2 = c.waitForPodLabel(ch, stopCh, &role)
 			return
 		}():
 		}
@@ -882,7 +884,7 @@ func (c *Cluster) Switchover(curMaster *v1.Pod, candidate spec.NamespacedName) (
 	// close the label waiting channel no sooner than the waiting goroutine terminates.
 	close(podLabelErr)
 
-	return
+	return err
 
 }
 

pkg/cluster/k8sres.go

@@ -7,13 +7,13 @@ import (
 
 	"github.com/Sirupsen/logrus"
 
+	"k8s.io/api/apps/v1beta1"
+	"k8s.io/api/core/v1"
+	policybeta1 "k8s.io/api/policy/v1beta1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/intstr"
-	"k8s.io/api/core/v1"
-	"k8s.io/api/apps/v1beta1"
-	policybeta1 "k8s.io/api/policy/v1beta1"
 
 	"github.com/zalando-incubator/postgres-operator/pkg/spec"
 	"github.com/zalando-incubator/postgres-operator/pkg/util"
@@ -90,7 +90,7 @@ func (c *Cluster) makeDefaultResources() spec.Resources {
 	defaultRequests := spec.ResourceDescription{CPU: config.DefaultCPURequest, Memory: config.DefaultMemoryRequest}
 	defaultLimits := spec.ResourceDescription{CPU: config.DefaultCPULimit, Memory: config.DefaultMemoryLimit}
 
-	return spec.Resources{ResourceRequest:defaultRequests, ResourceLimits:defaultLimits}
+	return spec.Resources{ResourceRequest: defaultRequests, ResourceLimits: defaultLimits}
 }
 
 func generateResourceRequirements(resources spec.Resources, defaultResources spec.Resources) (*v1.ResourceRequirements, error) {
@@ -366,7 +366,7 @@ func generateSidecarContainers(sidecars []spec.Sidecar,
 	volumeMounts []v1.VolumeMount, defaultResources spec.Resources,
 	superUserName string, credentialsSecretName string, logger *logrus.Entry) ([]v1.Container, error) {
 
-	if sidecars != nil && len(sidecars) > 0 {
+	if len(sidecars) > 0 {
 		result := make([]v1.Container, 0)
 		for index, sidecar := range sidecars {
 
@@ -716,7 +716,7 @@ func (c *Cluster) generateStatefulSet(spec *spec.PostgresSpec) (*v1beta1.Statefu
 		int64(c.OpConfig.PodTerminateGracePeriod.Seconds()),
 		c.OpConfig.PodServiceAccountName,
 		c.OpConfig.KubeIAMRole,
-		effectivePodPriorityClassName); err != nil{
+		effectivePodPriorityClassName); err != nil {
 		return nil, fmt.Errorf("could not generate pod template: %v", err)
 	}
 
@@ -804,11 +804,11 @@ func (c *Cluster) mergeSidecars(sidecars []spec.Sidecar) []spec.Sidecar {
 	return result
 }
 
-func (c *Cluster) getNumberOfInstances(spec *spec.PostgresSpec) (newcur int32) {
+func (c *Cluster) getNumberOfInstances(spec *spec.PostgresSpec) int32 {
 	min := c.OpConfig.MinInstances
 	max := c.OpConfig.MaxInstances
 	cur := spec.NumberOfInstances
-	newcur = cur
+	newcur := cur
 
 	if max >= 0 && newcur > max {
 		newcur = max
@@ -820,7 +820,7 @@ func (c *Cluster) getNumberOfInstances(spec *spec.PostgresSpec) (newcur int32) {
 		c.logger.Infof("adjusted number of instances from %d to %d (min: %d, max: %d)", cur, newcur, min, max)
 	}
 
-	return
+	return newcur
 }
 
 func generatePersistentVolumeClaimTemplate(volumeSize, volumeStorageClass string) (*v1.PersistentVolumeClaim, error) {
@@ -860,8 +860,8 @@ func generatePersistentVolumeClaimTemplate(volumeSize, volumeStorageClass string
 	return volumeClaim, nil
 }
 
-func (c *Cluster) generateUserSecrets() (secrets map[string]*v1.Secret) {
+func (c *Cluster) generateUserSecrets() map[string]*v1.Secret {
-	secrets = make(map[string]*v1.Secret, len(c.pgUsers))
+	secrets := make(map[string]*v1.Secret, len(c.pgUsers))
 	namespace := c.Namespace
 	for username, pgUser := range c.pgUsers {
 		//Skip users with no password i.e. human users (they'll be authenticated using pam)
@@ -878,7 +878,7 @@ func (c *Cluster) generateUserSecrets() (secrets map[string]*v1.Secret) {
 		}
 	}
 
-	return
+	return secrets
 }
 
 func (c *Cluster) generateSingleUserSecret(namespace string, pgUser spec.PgUser) *v1.Secret {

pkg/cluster/pg.go

@@ -183,32 +183,30 @@ func (c *Cluster) getDatabases() (dbs map[string]string, err error) {
 		dbs[datname] = owner
 	}
 
-	return
+	return dbs, err
 }
 
 // executeCreateDatabase creates new database with the given owner.
 // The caller is responsible for openinging and closing the database connection.
 func (c *Cluster) executeCreateDatabase(datname, owner string) error {
-	if !c.databaseNameOwnerValid(datname, owner) {
+	return c.execCreateOrAlterDatabase(datname, owner, createDatabaseSQL,
-		return nil
+		"creating database", "create database")
-	}
-	c.logger.Infof("creating database %q with owner %q", datname, owner)
-
-	if _, err := c.pgDb.Exec(fmt.Sprintf(createDatabaseSQL, datname, owner)); err != nil {
-		return fmt.Errorf("could not execute create database: %v", err)
-	}
-	return nil
 }
 
 // executeCreateDatabase changes the owner of the given database.
 // The caller is responsible for openinging and closing the database connection.
 func (c *Cluster) executeAlterDatabaseOwner(datname string, owner string) error {
+	return c.execCreateOrAlterDatabase(datname, owner, alterDatabaseOwnerSQL,
+		"changing owner for database", "alter database owner")
+}
+
+func (c *Cluster) execCreateOrAlterDatabase(datname, owner, statement, doing, operation string) error {
 	if !c.databaseNameOwnerValid(datname, owner) {
 		return nil
 	}
-	c.logger.Infof("changing database %q owner to %q", datname, owner)
+	c.logger.Infof("%s %q owner %q", doing, datname, owner)
-	if _, err := c.pgDb.Exec(fmt.Sprintf(alterDatabaseOwnerSQL, datname, owner)); err != nil {
+	if _, err := c.pgDb.Exec(fmt.Sprintf(statement, datname, owner)); err != nil {
-		return fmt.Errorf("could not execute alter database owner: %v", err)
+		return fmt.Errorf("could not execute %s: %v", operation, err)
 	}
 	return nil
 }

pkg/cluster/pod.go

@@ -225,7 +225,6 @@ func (c *Cluster) MigrateMasterPod(podName spec.NamespacedName) error {
 		c.logger.Warningf("single master pod for cluster %q, migration will cause longer downtime of the master instance", c.clusterName())
 	}
 
-
 	// there are two cases for each postgres cluster that has its master pod on the node to migrate from:
 	// - the cluster has some replicas - migrate one of those if necessary and failover to it
 	// - there are no replicas - just terminate the master and wait until it respawns

pkg/cluster/resources.go

@@ -633,27 +633,3 @@ func (c *Cluster) GetStatefulSet() *v1beta1.StatefulSet {
 func (c *Cluster) GetPodDisruptionBudget() *policybeta1.PodDisruptionBudget {
 	return c.PodDisruptionBudget
 }
-
-func (c *Cluster) createDatabases() error {
-	c.setProcessName("creating databases")
-
-	if len(c.Spec.Databases) == 0 {
-		return nil
-	}
-
-	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)
-		}
-	}()
-
-	for datname, owner := range c.Spec.Databases {
-		if err := c.executeCreateDatabase(datname, owner); err != nil {
-			return err
-		}
-	}
-	return nil
-}

pkg/cluster/sync.go

@@ -2,11 +2,9 @@ package cluster
 
 import (
 	"fmt"
-	"reflect"
-
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	policybeta1 "k8s.io/api/policy/v1beta1"
 	"k8s.io/api/core/v1"
+	policybeta1 "k8s.io/api/policy/v1beta1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	"github.com/zalando-incubator/postgres-operator/pkg/spec"
 	"github.com/zalando-incubator/postgres-operator/pkg/util"
@@ -17,7 +15,8 @@ import (
 
 // 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 *spec.Postgresql) (err error) {
+func (c *Cluster) Sync(newSpec *spec.Postgresql) error {
+	var err error
 	c.mu.Lock()
 	defer c.mu.Unlock()
 
@@ -34,7 +33,7 @@ func (c *Cluster) Sync(newSpec *spec.Postgresql) (err error) {
 
 	if err = c.initUsers(); err != nil {
 		err = fmt.Errorf("could not init users: %v", err)
-		return
+		return err
 	}
 
 	c.logger.Debugf("syncing secrets")
@@ -42,13 +41,13 @@ func (c *Cluster) Sync(newSpec *spec.Postgresql) (err error) {
 	//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
+		return err
 	}
 
 	c.logger.Debugf("syncing services")
 	if err = c.syncServices(); err != nil {
 		err = fmt.Errorf("could not sync services: %v", err)
-		return
+		return err
 	}
 
 	// potentially enlarge volumes before changing the statefulset. By doing that
@@ -60,14 +59,14 @@ func (c *Cluster) Sync(newSpec *spec.Postgresql) (err error) {
 	c.logger.Debugf("syncing persistent volumes")
 	if err = c.syncVolumes(); err != nil {
 		err = fmt.Errorf("could not sync persistent volumes: %v", err)
-		return
+		return err
 	}
 
 	c.logger.Debugf("syncing statefulsets")
 	if err = c.syncStatefulSet(); err != nil {
 		if !k8sutil.ResourceAlreadyExists(err) {
 			err = fmt.Errorf("could not sync statefulsets: %v", err)
-			return
+			return err
 		}
 	}
 
@@ -76,22 +75,22 @@ func (c *Cluster) Sync(newSpec *spec.Postgresql) (err error) {
 		c.logger.Debugf("syncing roles")
 		if err = c.syncRoles(); err != nil {
 			err = fmt.Errorf("could not sync roles: %v", err)
-			return
+			return err
 		}
 		c.logger.Debugf("syncing databases")
 		if err = c.syncDatabases(); err != nil {
 			err = fmt.Errorf("could not sync databases: %v", err)
-			return
+			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
+		return err
 	}
 
-	return
+	return err
 }
 
 func (c *Cluster) syncServices() error {
@@ -257,7 +256,9 @@ func (c *Cluster) syncStatefulSet() error {
 		podsRollingUpdateRequired = (len(pods) > 0)
 		if podsRollingUpdateRequired {
 			c.logger.Warningf("found pods from the previous statefulset: trigger rolling update")
-			c.applyRollingUpdateFlagforStatefulSet(podsRollingUpdateRequired)
+			if err := c.applyRollingUpdateFlagforStatefulSet(podsRollingUpdateRequired); err != nil {
+				return fmt.Errorf("could not set rolling update flag for the statefulset: %v", err)
+			}
 		}
 		c.logger.Infof("created missing statefulset %q", util.NameFromMeta(sset.ObjectMeta))
 
@@ -394,7 +395,7 @@ func (c *Cluster) syncSecrets() error {
 			// 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 %q from the infrastructure roles", secretSpec.Name)
-				if secret, err = c.KubeClient.Secrets(secretSpec.Namespace).Update(secretSpec); err != nil {
+				if _, err = c.KubeClient.Secrets(secretSpec.Namespace).Update(secretSpec); err != nil {
 					return fmt.Errorf("could not update infrastructure role secret for role %q: %v", secretUsername, err)
 				}
 			} else {
@@ -469,15 +470,6 @@ func (c *Cluster) syncVolumes() error {
 	return nil
 }
 
-func (c *Cluster) samePDBWith(pdb *policybeta1.PodDisruptionBudget) (match bool, reason string) {
-	match = reflect.DeepEqual(pdb.Spec, c.PodDisruptionBudget.Spec)
-	if !match {
-		reason = "new service spec doesn't match the current one"
-	}
-
-	return
-}
-
 func (c *Cluster) syncDatabases() error {
 	c.setProcessName("syncing databases")
 

pkg/controller/controller.go

@@ -169,7 +169,7 @@ func (c *Controller) initPodServiceAccount() {
 func (c *Controller) initRoleBinding() {
 
 	// service account on its own lacks any rights starting with k8s v1.8
-	// operator binds it to the cluster role with sufficient priviliges
+	// operator binds it to the cluster role with sufficient privileges
 	// we assume the role is created by the k8s administrator
 	if c.opConfig.PodServiceAccountRoleBindingDefinition == "" {
 		c.opConfig.PodServiceAccountRoleBindingDefinition = `
@@ -199,9 +199,9 @@ func (c *Controller) initRoleBinding() {
 
 	switch {
 	case err != nil:
-		panic(fmt.Errorf("Unable to parse the definiton of the role binding  for the pod service account definiton from the operator config map: %v", err))
+		panic(fmt.Errorf("Unable to parse the definition of the role binding for the pod service account definition from the operator config map: %v", err))
 	case groupVersionKind.Kind != "RoleBinding":
-		panic(fmt.Errorf("role binding definiton in the operator config map defines another type of resource: %v", groupVersionKind.Kind))
+		panic(fmt.Errorf("role binding definition in the operator config map defines another type of resource: %v", groupVersionKind.Kind))
 	default:
 		c.PodServiceAccountRoleBinding = obj.(*rbacv1beta1.RoleBinding)
 		c.PodServiceAccountRoleBinding.Namespace = ""

pkg/controller/pod.go

@@ -40,19 +40,9 @@ func (c *Controller) dispatchPodEvent(clusterName spec.NamespacedName, event spe
 }
 
 func (c *Controller) podAdd(obj interface{}) {
-	pod, ok := obj.(*v1.Pod)
+	if pod, ok := obj.(*v1.Pod); ok {
-	if !ok {
+		c.preparePodEventForDispatch(pod, nil, spec.EventAdd)
-		return
 	}
-
-	podEvent := spec.PodEvent{
-		PodName:         util.NameFromMeta(pod.ObjectMeta),
-		CurPod:          pod,
-		EventType:       spec.EventAdd,
-		ResourceVersion: pod.ResourceVersion,
-	}
-
-	c.dispatchPodEvent(c.podClusterName(pod), podEvent)
 }
 
 func (c *Controller) podUpdate(prev, cur interface{}) {
@@ -66,29 +56,24 @@ func (c *Controller) podUpdate(prev, cur interface{}) {
 		return
 	}
 
+	c.preparePodEventForDispatch(curPod, prevPod, spec.EventUpdate)
+}
+
+func (c *Controller) podDelete(obj interface{}) {
+
+	if pod, ok := obj.(*v1.Pod); ok {
+		c.preparePodEventForDispatch(pod, nil, spec.EventDelete)
+	}
+}
+
+func (c *Controller) preparePodEventForDispatch(curPod, prevPod *v1.Pod, event spec.EventType) {
 	podEvent := spec.PodEvent{
 		PodName:         util.NameFromMeta(curPod.ObjectMeta),
-		PrevPod:         prevPod,
 		CurPod:          curPod,
-		EventType:       spec.EventUpdate,
+		PrevPod:         prevPod,
+		EventType:       event,
 		ResourceVersion: curPod.ResourceVersion,
 	}
 
 	c.dispatchPodEvent(c.podClusterName(curPod), podEvent)
 }
-
-func (c *Controller) podDelete(obj interface{}) {
-	pod, ok := obj.(*v1.Pod)
-	if !ok {
-		return
-	}
-
-	podEvent := spec.PodEvent{
-		PodName:         util.NameFromMeta(pod.ObjectMeta),
-		CurPod:          pod,
-		EventType:       spec.EventDelete,
-		ResourceVersion: pod.ResourceVersion,
-	}
-
-	c.dispatchPodEvent(c.podClusterName(pod), podEvent)
-}

pkg/controller/postgresql.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"github.com/Sirupsen/logrus"
+
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/types"
@@ -130,7 +131,9 @@ type crdDecoder struct {
 }
 
 func (d *crdDecoder) Close() {
-	d.close()
+	if err := d.close(); err != nil {
+		fmt.Printf("error when closing CRDDecorer: %v\n", err)
+	}
 }
 
 func (d *crdDecoder) Decode() (action watch.EventType, object runtime.Object, err error) {
@@ -526,7 +529,6 @@ func (c *Controller) submitRBACCredentials(event spec.ClusterEvent) error {
 	if err := c.createRoleBindings(namespace); err != nil {
 		return fmt.Errorf("could not create role binding %v : %v", c.PodServiceAccountRoleBinding.Name, err)
 	}
-
 	c.namespacesWithDefinedRBAC.Store(namespace, true)
 	return nil
 }

pkg/spec/postgresql.go

@@ -156,7 +156,9 @@ var (
 // will not contain any private fields not-reachable to deepcopy. This should be ok,
 // since Error is never read from a Kubernetes object.
 func (p *Postgresql) Clone() *Postgresql {
-	if p == nil {return nil}
+	if p == nil {
+		return nil
+	}
 	c := deepcopy.Copy(p).(*Postgresql)
 	c.Error = nil
 	return c
@@ -166,11 +168,12 @@ func (p *Postgresql) DeepCopyInto(out *Postgresql) {
 	if p != nil {
 		*out = deepcopy.Copy(*p).(Postgresql)
 	}
-	return
 }
 
 func (p *Postgresql) DeepCopy() *Postgresql {
-	if p == nil { return nil }
+	if p == nil {
+		return nil
+	}
 	out := new(Postgresql)
 	p.DeepCopyInto(out)
 	return out
@@ -308,7 +311,6 @@ func validateCloneClusterDescription(clone *CloneDescription) error {
 type postgresqlListCopy PostgresqlList
 type postgresqlCopy Postgresql
 
-
 // UnmarshalJSON converts a JSON into the PostgreSQL object.
 func (p *Postgresql) UnmarshalJSON(data []byte) error {
 	var tmp postgresqlCopy
@@ -359,7 +361,9 @@ func (pl *PostgresqlList) UnmarshalJSON(data []byte) error {
 }
 
 func (pl *PostgresqlList) DeepCopy() *PostgresqlList {
-	if pl == nil { return nil }
+	if pl == nil {
+		return nil
+	}
 	out := new(PostgresqlList)
 	pl.DeepCopyInto(out)
 	return out
@@ -369,7 +373,6 @@ func (pl *PostgresqlList) DeepCopyInto(out *PostgresqlList) {
 	if pl != nil {
 		*out = deepcopy.Copy(*pl).(PostgresqlList)
 	}
-	return
 }
 
 func (pl *PostgresqlList) DeepCopyObject() runtime.Object {
@@ -379,7 +382,6 @@ func (pl *PostgresqlList) DeepCopyObject() runtime.Object {
 	return nil
 }
 
-
 func (status PostgresStatus) Success() bool {
 	return status != ClusterStatusAddFailed &&
 		status != ClusterStatusUpdateFailed &&

pkg/util/config/crd_config.go

@@ -3,11 +3,11 @@ package config
 import (
 	"encoding/json"
 
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-
 	"github.com/zalando-incubator/postgres-operator/pkg/spec"
-	"github.com/mohae/deepcopy"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+
+	"github.com/mohae/deepcopy"
 )
 
 type OperatorConfiguration struct {
@@ -159,11 +159,12 @@ func (opc *OperatorConfiguration) DeepCopyInto(out *OperatorConfiguration) {
 	if opc != nil {
 		*out = deepcopy.Copy(*opc).(OperatorConfiguration)
 	}
-	return
 }
 
 func (opc *OperatorConfiguration) DeepCopy() *OperatorConfiguration {
-	if opc == nil { return nil }
+	if opc == nil {
+		return nil
+	}
 	out := new(OperatorConfiguration)
 	opc.DeepCopyInto(out)
 	return out
@@ -189,11 +190,12 @@ func (opcl *OperatorConfigurationList) DeepCopyInto(out *OperatorConfigurationLi
 	if opcl != nil {
 		*out = deepcopy.Copy(*opcl).(OperatorConfigurationList)
 	}
-	return
 }
 
 func (opcl *OperatorConfigurationList) DeepCopy() *OperatorConfigurationList {
-	if opcl == nil { return nil }
+	if opcl == nil {
+		return nil
+	}
 	out := new(OperatorConfigurationList)
 	opcl.DeepCopyInto(out)
 	return out
@@ -205,4 +207,3 @@ func (opcl *OperatorConfigurationList) DeepCopyObject() runtime.Object {
 	}
 	return nil
 }
-

pkg/util/patroni/patroni.go

@@ -47,7 +47,7 @@ func apiURL(masterPod *v1.Pod) string {
 	return fmt.Sprintf("http://%s:%d", masterPod.Status.PodIP, apiPort)
 }
 
-func (p *Patroni) httpPostOrPatch(method string, url string, body *bytes.Buffer) error {
+func (p *Patroni) httpPostOrPatch(method string, url string, body *bytes.Buffer) (err error) {
 	request, err := http.NewRequest(method, url, body)
 	if err != nil {
 		return fmt.Errorf("could not create request: %v", err)
@@ -59,7 +59,16 @@ func (p *Patroni) httpPostOrPatch(method string, url string, body *bytes.Buffer)
 	if err != nil {
 		return fmt.Errorf("could not make request: %v", err)
 	}
-	defer resp.Body.Close()
+	defer func() {
+		if err2 := resp.Body.Close(); err2 != nil {
+			if err != nil {
+				err = fmt.Errorf("could not close request: %v, prior error: %v", err2, err)
+			} else {
+				err = fmt.Errorf("could not close request: %v", err2)
+			}
+			return
+		}
+	}()
 
 	if resp.StatusCode != http.StatusOK {
 		bodyBytes, err := ioutil.ReadAll(resp.Body)
@@ -83,6 +92,7 @@ func (p *Patroni) Switchover(master *v1.Pod, candidate string) error {
 }
 
 //TODO: add an option call /patroni to check if it is necessary to restart the server
+
 //SetPostgresParameters sets Postgres options via Patroni patch API call.
 func (p *Patroni) SetPostgresParameters(server *v1.Pod, parameters map[string]string) error {
 	buf := &bytes.Buffer{}

pkg/util/teams/teams.go

@@ -76,17 +76,15 @@ func (t *API) TeamInfo(teamID, token string) (tm *Team, err error) {
 	t.logger.Debugf("request url: %s", url)
 	req, err = http.NewRequest("GET", url, nil)
 	if err != nil {
-		return
+		return nil, err
 	}
 
 	req.Header.Add("Authorization", "Bearer "+token)
-	resp, err = t.httpClient.Do(req)
+	if resp, err = t.httpClient.Do(req); err != nil {
-	if err != nil {
+		return nil, err
-		return
 	}
 	defer func() {
-		closeErr := resp.Body.Close()
+		if closeErr := resp.Body.Close(); closeErr != nil {
-		if closeErr != nil {
 			err = fmt.Errorf("error when closing response: %v", closeErr)
 		}
 	}()
@@ -95,27 +93,20 @@ func (t *API) TeamInfo(teamID, token string) (tm *Team, err error) {
 		d := json.NewDecoder(resp.Body)
 		err = d.Decode(&raw)
 		if err != nil {
-			err = fmt.Errorf("team API query failed with status code %d and malformed response: %v", resp.StatusCode, err)
+			return nil, fmt.Errorf("team API query failed with status code %d and malformed response: %v", resp.StatusCode, err)
-			return
 		}
 
 		if errMessage, ok := raw["error"]; ok {
-			err = fmt.Errorf("team API query failed with status code %d and message: '%v'", resp.StatusCode, string(errMessage))
+			return nil, fmt.Errorf("team API query failed with status code %d and message: '%v'", resp.StatusCode, string(errMessage))
-			return
 		}
-		err = fmt.Errorf("team API query failed with status code %d", resp.StatusCode)
+		return nil, fmt.Errorf("team API query failed with status code %d", resp.StatusCode)
-
-		return
 	}
 
 	tm = &Team{}
 	d := json.NewDecoder(resp.Body)
-	err = d.Decode(tm)
+	if err = d.Decode(tm); err != nil {
-	if err != nil {
+		return nil, fmt.Errorf("could not parse team API response: %v", err)
-		err = fmt.Errorf("could not parse team API response: %v", err)
-		tm = nil
-		return
 	}
 
-	return
+	return tm, nil
 }

pkg/util/users/users.go

@@ -30,8 +30,9 @@ type DefaultUserSyncStrategy struct {
 
 // ProduceSyncRequests figures out the types of changes that need to happen with the given users.
 func (strategy DefaultUserSyncStrategy) ProduceSyncRequests(dbUsers spec.PgUserMap,
-	newUsers spec.PgUserMap) (reqs []spec.PgSyncUserRequest) {
+	newUsers spec.PgUserMap) []spec.PgSyncUserRequest {
 
+	var reqs []spec.PgSyncUserRequest
 	// No existing roles are deleted or stripped of role memebership/flags
 	for name, newUser := range newUsers {
 		dbUser, exists := dbUsers[name]
@@ -66,7 +67,7 @@ func (strategy DefaultUserSyncStrategy) ProduceSyncRequests(dbUsers spec.PgUserM
 		}
 	}
 
-	return
+	return reqs
 }
 
 // ExecuteSyncRequests makes actual database changes from the requests passed in its arguments.
@@ -102,7 +103,7 @@ func (strategy DefaultUserSyncStrategy) alterPgUserSet(user spec.PgUser, db *sql
 	return
 }
 
-func (strategy DefaultUserSyncStrategy) createPgUser(user spec.PgUser, db *sql.DB) (err error) {
+func (strategy DefaultUserSyncStrategy) createPgUser(user spec.PgUser, db *sql.DB) error {
 	var userFlags []string
 	var userPassword string
 
@@ -120,16 +121,14 @@ func (strategy DefaultUserSyncStrategy) createPgUser(user spec.PgUser, db *sql.D
 	}
 	query := fmt.Sprintf(createUserSQL, user.Name, strings.Join(userFlags, " "), userPassword)
 
-	_, err = db.Exec(query) // TODO: Try several times
+	if _, err := db.Exec(query); err != nil { // TODO: Try several times
-	if err != nil {
+		return fmt.Errorf("dB error: %v, query: %s", err, query)
-		err = fmt.Errorf("dB error: %v, query: %s", err, query)
-		return
 	}
 
-	return
+	return nil
 }
 
-func (strategy DefaultUserSyncStrategy) alterPgUser(user spec.PgUser, db *sql.DB) (err error) {
+func (strategy DefaultUserSyncStrategy) alterPgUser(user spec.PgUser, db *sql.DB) error {
 	var resultStmt []string
 
 	if user.Password != "" || len(user.Flags) > 0 {
@@ -140,19 +139,16 @@ func (strategy DefaultUserSyncStrategy) alterPgUser(user spec.PgUser, db *sql.DB
 		grantStmt := produceGrantStmt(user)
 		resultStmt = append(resultStmt, grantStmt)
 	}
-	if len(resultStmt) == 0 {
-		return nil
-	}
 
+	if len(resultStmt) > 0 {
 		query := fmt.Sprintf(doBlockStmt, strings.Join(resultStmt, ";"))
 
-	_, err = db.Exec(query) // TODO: Try several times
+		if _, err := db.Exec(query); err != nil { // TODO: Try several times
-	if err != nil {
+			return fmt.Errorf("dB error: %v query %s", err, query)
-		err = fmt.Errorf("dB error: %v query %s", err, query)
+		}
-		return
 	}
 
-	return
+	return nil
 }
 
 func produceAlterStmt(user spec.PgUser) string {
@@ -205,7 +201,7 @@ func quoteParameterValue(name, val string) string {
 		// containing spaces (but something more complex, like double quotes inside double quotes or spaces
 		// in the schema name would break the parsing code in the operator.)
 		if start == '\'' && end == '\'' {
-			return fmt.Sprintf("%s", val[1:len(val)-1])
+			return val[1 : len(val)-1]
 		}
 
 		return val