Merge pull request #1113 from rabbitmq/cluster-size-hint

Set cluster size hint

Author: ChunyiLyu

.github/workflows/pr.yml

@@ -53,7 +53,7 @@ jobs:
         k8s:
         - v1.24.1
         rabbitmq-image:
-        - rabbitmq:3.9.0-management # minimum supported version
+        - rabbitmq:3.9.9-management # minimum supported version
         - rabbitmq:3.10-management
         - pivotalrabbitmq/rabbitmq:master-otp-min
         - pivotalrabbitmq/rabbitmq:master-otp-max

README.md

@@ -37,7 +37,7 @@ under `site/kubernetes`.
 
 ## Supported Versions
 
-The operator deploys RabbitMQ `3.10.2` by default, and supports versions from `3.9` upwards. The operator requires Kubernetes `1.19` or newer.
+The operator deploys RabbitMQ `3.10.2` by default, and supports versions from `3.9.9` upwards. The operator requires Kubernetes `1.19` or newer.
 
 ## Versioning
 

internal/resource/configmap.go

@@ -11,6 +11,7 @@ package resource
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 
 	"sigs.k8s.io/controller-runtime/pkg/client"
@@ -27,12 +28,12 @@ import (
 const (
 	ServerConfigMapName = "server-conf"
 	defaultRabbitmqConf = `
+queue_master_locator = min-masters
+disk_free_limit.absolute = 2GB
+cluster_partition_handling = pause_minority
 cluster_formation.peer_discovery_backend = rabbit_peer_discovery_k8s
 cluster_formation.k8s.host = kubernetes.default
-cluster_formation.k8s.address_type = hostname
-cluster_partition_handling = pause_minority
-queue_master_locator = min-masters
-disk_free_limit.absolute = 2GB`
+cluster_formation.k8s.address_type = hostname`
 
 	defaultTLSConf = `
 ssl_options.certfile = /etc/rabbitmq-tls/tls.crt
@@ -89,6 +90,10 @@ func (builder *ServerConfigMapBuilder) Update(object client.Object) error {
 	}
 	defaultSection := operatorConfiguration.Section("")
 
+	if _, err := defaultSection.NewKey("cluster_formation.target_cluster_size_hint", strconv.Itoa(int(*builder.Instance.Spec.Replicas))); err != nil {
+		return err
+	}
+
 	if _, err := defaultSection.NewKey("cluster_name", builder.Instance.Name); err != nil {
 		return err
 	}

internal/resource/configmap_test.go

@@ -12,6 +12,7 @@ package resource_test
 import (
 	"bytes"
 	"fmt"
+	"k8s.io/utils/pointer"
 
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
@@ -27,13 +28,14 @@ import (
 
 func defaultRabbitmqConf(instanceName string) string {
 	return iniString(`
-cluster_formation.peer_discovery_backend = rabbit_peer_discovery_k8s
-cluster_formation.k8s.host               = kubernetes.default
-cluster_formation.k8s.address_type       = hostname
-cluster_partition_handling               = pause_minority
-queue_master_locator                     = min-masters
-disk_free_limit.absolute                 = 2GB
-cluster_name                             = ` + instanceName)
+queue_master_locator                       = min-masters
+disk_free_limit.absolute                   = 2GB
+cluster_partition_handling                 = pause_minority
+cluster_formation.peer_discovery_backend   = rabbit_peer_discovery_k8s
+cluster_formation.k8s.host                 = kubernetes.default
+cluster_formation.k8s.address_type         = hostname
+cluster_formation.target_cluster_size_hint = 1
+cluster_name                               = ` + instanceName)
 }
 
 var _ = Describe("GenerateServerConfigMap", func() {
@@ -143,6 +145,16 @@ var _ = Describe("GenerateServerConfigMap", func() {
 			Expect(configMap.Data).To(HaveKeyWithValue("operatorDefaults.conf", expectedConfiguration))
 		})
 
+		It("sets cluster size hint", func() {
+			builder.Instance.Spec.Rabbitmq.AdditionalConfig = ""
+			builder.Instance.Spec.Replicas = pointer.Int32Ptr(100)
+
+			Expect(configMapBuilder.Update(configMap)).To(Succeed())
+			operatorDefaultConf, err := ini.Load([]byte(configMap.Data["operatorDefaults.conf"]))
+			Expect(err).To(Not(HaveOccurred()))
+			Expect(operatorDefaultConf.Section("").KeysHash()).To(HaveKeyWithValue("cluster_formation.target_cluster_size_hint", "100"))
+		})
+
 		When("valid userDefinedConfiguration is provided", func() {
 			It("adds configurations in a new rabbitmq configuration", func() {
 				userDefinedConfiguration := "cluster_formation.peer_discovery_backend = my-backend\n" +
@@ -375,6 +387,7 @@ CONSOLE_LOG=new`
 						Name: "rabbit-tls",
 					},
 					Spec: rabbitmqv1beta1.RabbitmqClusterSpec{
+						Replicas: pointer.Int32Ptr(1),
 						TLS: rabbitmqv1beta1.TLSSpec{
 							SecretName:             "some-secret",
 							DisableNonTLSListeners: true,
@@ -406,6 +419,7 @@ CONSOLE_LOG=new`
 						Name: "rabbit-tls",
 					},
 					Spec: rabbitmqv1beta1.RabbitmqClusterSpec{
+						Replicas: pointer.Int32Ptr(1),
 						TLS: rabbitmqv1beta1.TLSSpec{
 							SecretName:             "some-secret",
 							DisableNonTLSListeners: true,
@@ -453,6 +467,7 @@ CONSOLE_LOG=new`
 						Name: "rabbit-tls",
 					},
 					Spec: rabbitmqv1beta1.RabbitmqClusterSpec{
+						Replicas: pointer.Int32Ptr(1),
 						TLS: rabbitmqv1beta1.TLSSpec{
 							SecretName:             "some-secret",
 							CaSecretName:           "some-mutual-secret",