Refactor needConnectionPooler

Have one unified function to tell if any connection pooler is required

Add a helper function to list the roles that require connection pooler,
helps in avoiding duplication of code

docs/reference/cluster_manifest.md

@@ -392,8 +392,10 @@ CPU and memory limits for the sidecar container.
 
 Parameters are grouped under the `connectionPooler` top-level key and specify
 configuration for connection pooler. If this section is not empty, a connection
-pooler will be created for a database even if `enableConnectionPooler` is not
+pooler will be created for master service only even if `enableConnectionPooler`
-present.
+is not present. But if this section is present then it defines the configuration
+for both master and replica pooler services (if `enableReplicaConnectionPooler`
+ is enabled).
 
 * **numberOfInstances**
   How many instances of connection pooler to create.

pkg/cluster/cluster.go

@@ -55,10 +55,8 @@ type Config struct {
 
 // K8S objects that are belongs to a connection pooler
 type ConnectionPoolerObjects struct {
-	Deployment     *appsv1.Deployment
+	Deployment map[PostgresRole]*appsv1.Deployment
-	ReplDeployment *appsv1.Deployment
+	Service    map[PostgresRole]*v1.Service
-	Service        *v1.Service
-	ReplService    *v1.Service
 
 	// It could happen that a connection pooler was enabled, but the operator
 	// was not able to properly process a corresponding event or was restarted.
@@ -348,7 +346,8 @@ func (c *Cluster) Create() error {
 	//
 	// Do not consider connection pooler as a strict requirement, and if
 	// something fails, report warning
-	if c.needMasterConnectionPooler() || c.needReplicaConnectionPooler() {
+	roles := c.RolesConnectionPooler()
+	for _, r := range roles {
 		if c.ConnectionPooler != nil {
 			c.logger.Warning("Connection pooler already exists in the cluster")
 			return nil
@@ -359,7 +358,7 @@ func (c *Cluster) Create() error {
 			return nil
 		}
 		c.logger.Infof("connection pooler %q has been successfully created",
-			util.NameFromMeta(connectionPooler.Deployment.ObjectMeta))
+			util.NameFromMeta(connectionPooler.Deployment[r].ObjectMeta))
 	}
 
 	return nil

pkg/cluster/resources.go

@@ -126,9 +126,10 @@ func (c *Cluster) createConnectionPooler(lookup InstallFunction) (*ConnectionPoo
 		msg = "could not prepare database for connection pooler: %v"
 		return nil, fmt.Errorf(msg, err)
 	}
-	if c.needMasterConnectionPooler() {
+	if c.needConnectionPooler() {
-
+		roles := c.RolesConnectionPooler()
-		deploymentSpec, err := c.generateConnectionPoolerDeployment(&c.Spec, Master)
+		for _, r := range roles {
+			deploymentSpec, err := c.generateConnectionPoolerDeployment(&c.Spec, r)
 			if err != nil {
 				msg = "could not generate deployment for connection pooler: %v"
 				return nil, fmt.Errorf(msg, err)
@@ -145,7 +146,7 @@ func (c *Cluster) createConnectionPooler(lookup InstallFunction) (*ConnectionPoo
 				return nil, err
 			}
 
-		serviceSpec := c.generateConnectionPoolerService(&c.Spec, Master)
+			serviceSpec := c.generateConnectionPoolerService(&c.Spec, r)
 			service, err := c.KubeClient.
 				Services(serviceSpec.Namespace).
 				Create(context.TODO(), serviceSpec, metav1.CreateOptions{})
@@ -153,54 +154,12 @@ func (c *Cluster) createConnectionPooler(lookup InstallFunction) (*ConnectionPoo
 			if err != nil {
 				return nil, err
 			}
-		c.ConnectionPooler = &ConnectionPoolerObjects{
+			c.ConnectionPooler.Deployment[r] = deployment
-			Deployment: deployment,
+			c.ConnectionPooler.Service[r] = service
-			Service:    service,
+
-		}
 			c.logger.Debugf("created new connection pooler %q, uid: %q",
 				util.NameFromMeta(deployment.ObjectMeta), deployment.UID)
-
 		}
-
-	if c.needReplicaConnectionPooler() {
-
-		repldeploymentSpec, err := c.generateConnectionPoolerDeployment(&c.Spec, Replica)
-		if err != nil {
-			msg = "could not generate deployment for connection pooler: %v"
-			return nil, fmt.Errorf(msg, err)
-		}
-
-		// client-go does retry 10 times (with NoBackoff by default) when the API
-		// believe a request can be retried and returns Retry-After header. This
-		// should be good enough to not think about it here.
-		repldeployment, err := c.KubeClient.
-			Deployments(repldeploymentSpec.Namespace).
-			Create(context.TODO(), repldeploymentSpec, metav1.CreateOptions{})
-
-		if err != nil {
-			return nil, err
-		}
-
-		replServiceSpec := c.generateConnectionPoolerService(&c.Spec, Replica)
-		replService, err := c.KubeClient.
-			Services(replServiceSpec.Namespace).
-			Create(context.TODO(), replServiceSpec, metav1.CreateOptions{})
-
-		if err != nil {
-			return nil, err
-		}
-
-		if c.needMasterConnectionPooler() {
-			c.ConnectionPooler.ReplDeployment = repldeployment
-			c.ConnectionPooler.ReplService = replService
-		} else {
-			c.ConnectionPooler = &ConnectionPoolerObjects{
-				ReplDeployment: repldeployment,
-				ReplService:    replService,
-			}
-		}
-		c.logger.Debugf("created new connection pooler for replica %q, uid: %q",
-			util.NameFromMeta(repldeployment.ObjectMeta), repldeployment.UID)
 	}
 
 	return c.ConnectionPooler, nil
@@ -221,12 +180,8 @@ func (c *Cluster) deleteConnectionPooler(role PostgresRole) (err error) {
 	// is somehow empty, try to delete based on what would we generate
 	var deploymentName string
 	var deployment *appsv1.Deployment
+	deployment = c.ConnectionPooler.Deployment[role]
 
-	if role == Master {
-		deployment = c.ConnectionPooler.Deployment
-	} else {
-		deployment = c.ConnectionPooler.ReplDeployment
-	}
 	if deployment != nil {
 		deploymentName = deployment.Name
 	}
@@ -249,11 +204,8 @@ func (c *Cluster) deleteConnectionPooler(role PostgresRole) (err error) {
 
 	// Repeat the same for the service object
 	var service *v1.Service
-	if role == Master {
+	service = c.ConnectionPooler.Service[role]
-		service = c.ConnectionPooler.Service
+
-	} else {
-		service = c.ConnectionPooler.ReplService
-	}
 	serviceName := c.connectionPoolerName(role)
 
 	if service != nil {
@@ -909,9 +861,9 @@ func (c *Cluster) GetPodDisruptionBudget() *policybeta1.PodDisruptionBudget {
 
 // Perform actual patching of a connection pooler deployment, assuming that all
 // the check were already done before.
-func (c *Cluster) updateConnectionPoolerDeployment(oldDeploymentSpec, newDeployment *appsv1.Deployment) (*appsv1.Deployment, error) {
+func (c *Cluster) updateConnectionPoolerDeployment(oldDeploymentSpec, newDeployment *appsv1.Deployment, role PostgresRole) (*appsv1.Deployment, error) {
 	c.setProcessName("updating connection pooler")
-	if c.ConnectionPooler == nil || c.ConnectionPooler.Deployment == nil {
+	if c.ConnectionPooler == nil || c.ConnectionPooler.Deployment[role] == nil {
 		return nil, fmt.Errorf("there is no connection pooler in the cluster")
 	}
 
@@ -924,9 +876,9 @@ func (c *Cluster) updateConnectionPoolerDeployment(oldDeploymentSpec, newDeploym
 	// worker at one time will try to update it chances of conflicts are
 	// minimal.
 	deployment, err := c.KubeClient.
-		Deployments(c.ConnectionPooler.Deployment.Namespace).Patch(
+		Deployments(c.ConnectionPooler.Deployment[role].Namespace).Patch(
 		context.TODO(),
-		c.ConnectionPooler.Deployment.Name,
+		c.ConnectionPooler.Deployment[role].Name,
 		types.MergePatchType,
 		patchData,
 		metav1.PatchOptions{},
@@ -935,21 +887,21 @@ func (c *Cluster) updateConnectionPoolerDeployment(oldDeploymentSpec, newDeploym
 		return nil, fmt.Errorf("could not patch deployment: %v", err)
 	}
 
-	c.ConnectionPooler.Deployment = deployment
+	c.ConnectionPooler.Deployment[role] = deployment
 
 	return deployment, nil
 }
 
 //updateConnectionPoolerAnnotations updates the annotations of connection pooler deployment
-func (c *Cluster) updateConnectionPoolerAnnotations(annotations map[string]string) (*appsv1.Deployment, error) {
+func (c *Cluster) updateConnectionPoolerAnnotations(annotations map[string]string, role PostgresRole) (*appsv1.Deployment, error) {
 	c.logger.Debugf("updating connection pooler annotations")
 	patchData, err := metaAnnotationsPatch(annotations)
 	if err != nil {
 		return nil, fmt.Errorf("could not form patch for the deployment metadata: %v", err)
 	}
-	result, err := c.KubeClient.Deployments(c.ConnectionPooler.Deployment.Namespace).Patch(
+	result, err := c.KubeClient.Deployments(c.ConnectionPooler.Deployment[role].Namespace).Patch(
 		context.TODO(),
-		c.ConnectionPooler.Deployment.Name,
+		c.ConnectionPooler.Deployment[role].Name,
 		types.MergePatchType,
 		[]byte(patchData),
 		metav1.PatchOptions{},

pkg/cluster/sync.go

@@ -848,7 +848,7 @@ func (c *Cluster) syncConnectionPooler(oldSpec,
 	var newNeedConnectionPooler, oldNeedConnectionPooler bool
 
 	// Check and perform the sync requirements for each of the roles.
-	for _, role := range [2]PostgresRole{Master, Replica} {
+	for _, role := range c.RolesConnectionPooler() {
 		if role == Master {
 			newNeedConnectionPooler = c.needMasterConnectionPoolerWorker(&newSpec.Spec)
 			oldNeedConnectionPooler = c.needMasterConnectionPoolerWorker(&oldSpec.Spec)
@@ -858,6 +858,8 @@ func (c *Cluster) syncConnectionPooler(oldSpec,
 		}
 		if c.ConnectionPooler == nil {
 			c.ConnectionPooler = &ConnectionPoolerObjects{}
+			c.ConnectionPooler.Deployment = make(map[PostgresRole]*appsv1.Deployment)
+			c.ConnectionPooler.Service = make(map[PostgresRole]*v1.Service)
 		}
 
 		if newNeedConnectionPooler {
@@ -909,29 +911,13 @@ func (c *Cluster) syncConnectionPooler(oldSpec,
 
 		if !oldNeedConnectionPooler && !newNeedConnectionPooler {
 			// delete and cleanup resources if not empty
-			if role == Master {
 			if c.ConnectionPooler != nil &&
-					(c.ConnectionPooler.Deployment != nil ||
+				(c.ConnectionPooler.Deployment[role] != nil ||
-						c.ConnectionPooler.Service != nil) {
+					c.ConnectionPooler.Service[role] != nil) {
 
 				if err = c.deleteConnectionPooler(role); err != nil {
 					c.logger.Warningf("could not remove connection pooler: %v", err)
 				}
-
-				} else if c.ConnectionPooler.ReplDeployment == nil && c.ConnectionPooler.ReplService == nil {
-					c.ConnectionPooler = nil
-				}
-			} else {
-				if c.ConnectionPooler != nil &&
-					(c.ConnectionPooler.ReplDeployment != nil ||
-						c.ConnectionPooler.ReplService != nil) {
-
-					if err = c.deleteConnectionPooler(role); err != nil {
-						c.logger.Warningf("could not remove connection pooler: %v", err)
-					}
-				} else if c.ConnectionPooler.Deployment == nil && c.ConnectionPooler.Service == nil {
-					c.ConnectionPooler = nil
-				}
 			}
 		}
 	}
@@ -967,22 +953,13 @@ func (c *Cluster) syncConnectionPoolerWorker(oldSpec, newSpec *acidv1.Postgresql
 		if err != nil {
 			return NoSync, err
 		}
-
+		c.ConnectionPooler.Deployment[role] = deployment
-		if role == Master {
-			c.ConnectionPooler.Deployment = deployment
-		} else {
-			c.ConnectionPooler.ReplDeployment = deployment
-		}
 	} else if err != nil {
 		msg := "could not get connection pooler deployment to sync: %v"
 		return NoSync, fmt.Errorf(msg, err)
 	} else {
-		if role == Master {
+		c.ConnectionPooler.Deployment[role] = deployment
-			c.ConnectionPooler.Deployment = deployment
-		} else {
 
-			c.ConnectionPooler.ReplDeployment = deployment
-		}
 		// actual synchronization
 		oldConnectionPooler := oldSpec.Spec.ConnectionPooler
 		newConnectionPooler := newSpec.Spec.ConnectionPooler
@@ -1007,34 +984,33 @@ func (c *Cluster) syncConnectionPoolerWorker(oldSpec, newSpec *acidv1.Postgresql
 		reason := append(specReason, defaultsReason...)
 
 		if specSync || defaultsSync {
-
+			c.logger.Infof("Update connection pooler deployment %s, reason: %+v",
+				c.connectionPoolerName(role), reason)
 			newDeploymentSpec, err := c.generateConnectionPoolerDeployment(&newSpec.Spec, role)
 			if err != nil {
 				msg := "could not generate deployment for connection pooler: %v"
 				return reason, fmt.Errorf(msg, err)
 			}
 
-			oldDeploymentSpec := c.ConnectionPooler.Deployment
+			oldDeploymentSpec := c.ConnectionPooler.Deployment[role]
 
 			deployment, err := c.updateConnectionPoolerDeployment(
 				oldDeploymentSpec,
-				newDeploymentSpec)
+				newDeploymentSpec,
+				role)
 
 			if err != nil {
 				return reason, err
 			}
-			if role == Master {
+			c.ConnectionPooler.Deployment[role] = deployment
-				c.ConnectionPooler.Deployment = deployment
+
-			} else {
-				c.ConnectionPooler.ReplDeployment = deployment
-			}
 			return reason, nil
 		}
 	}
 
-	newAnnotations := c.AnnotationsToPropagate(c.ConnectionPooler.Deployment.Annotations)
+	newAnnotations := c.AnnotationsToPropagate(c.ConnectionPooler.Deployment[role].Annotations)
 	if newAnnotations != nil {
-		c.updateConnectionPoolerAnnotations(newAnnotations)
+		c.updateConnectionPoolerAnnotations(newAnnotations, role)
 	}
 
 	service, err := c.KubeClient.
@@ -1053,22 +1029,14 @@ func (c *Cluster) syncConnectionPoolerWorker(oldSpec, newSpec *acidv1.Postgresql
 		if err != nil {
 			return NoSync, err
 		}
-		if role == Master {
+		c.ConnectionPooler.Service[role] = service
-			c.ConnectionPooler.Service = service
-		} else {
-			c.ConnectionPooler.ReplService = service
-		}
 
 	} else if err != nil {
 		msg := "could not get connection pooler service to sync: %v"
 		return NoSync, fmt.Errorf(msg, err)
 	} else {
 		// Service updates are not supported and probably not that useful anyway
-		if role == Master {
+		c.ConnectionPooler.Service[role] = service
-			c.ConnectionPooler.Service = service
-		} else {
-			c.ConnectionPooler.ReplService = service
-		}
 	}
 
 	return NoSync, nil

pkg/cluster/util.go

@@ -521,17 +521,36 @@ func (c *Cluster) patroniKubernetesUseConfigMaps() bool {
 
 // isConnectionPoolerEnabled
 func (c *Cluster) needMasterConnectionPoolerWorker(spec *acidv1.PostgresSpec) bool {
-	return (nil != spec.EnableConnectionPooler && *spec.EnableConnectionPooler) || (spec.ConnectionPooler != nil && spec.EnableConnectionPooler == nil)
+	return (spec.EnableConnectionPooler != nil && *spec.EnableConnectionPooler) || (spec.ConnectionPooler != nil && spec.EnableConnectionPooler == nil)
 }
 
 func (c *Cluster) needReplicaConnectionPoolerWorker(spec *acidv1.PostgresSpec) bool {
-	return nil != spec.EnableReplicaConnectionPooler && *spec.EnableReplicaConnectionPooler
+	return spec.EnableReplicaConnectionPooler != nil && *spec.EnableReplicaConnectionPooler
 }
 
 func (c *Cluster) needMasterConnectionPooler() bool {
 	return c.needMasterConnectionPoolerWorker(&c.Spec)
 }
 
+func (c *Cluster) needConnectionPooler() bool {
+	return c.needMasterConnectionPoolerWorker(&c.Spec) || c.needReplicaConnectionPoolerWorker(&c.Spec)
+}
+
+// RolesConnectionPooler gives the list of roles which need connection pooler
+func (c *Cluster) RolesConnectionPooler() []PostgresRole {
+	roles := []PostgresRole{}
+	i := 0
+
+	if c.needMasterConnectionPoolerWorker(&c.Spec) {
+		roles[i] = Master
+		i = i + 1
+	}
+	if c.needMasterConnectionPoolerWorker(&c.Spec) {
+		roles[i] = Replica
+	}
+	return roles
+}
+
 func (c *Cluster) needReplicaConnectionPooler() bool {
 	return c.needReplicaConnectionPoolerWorker(&c.Spec)
 }