Use Elasticsearch readiness port

pkg/apis/elasticsearch/v1/fields.go

@@ -4,6 +4,12 @@
 
 package v1
 
+import "github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/version"
+
+// as of 8.2.0 a simplified unauthenticated readiness port is available which takes cluster membership into account
+// see https://www.elastic.co/guide/en/elasticsearch/reference/current/advanced-configuration.html#readiness-tcp-port
+var MinReadinessPortVersion = version.MinFor(8, 2, 0)
+
 const (
  ClusterName = "cluster.name"
 
@@ -14,6 +20,8 @@ const (
  DiscoverySeedProviders = "discovery.seed_providers" // ES >= 7.X
  DiscoverySeedHosts = "discovery.seed_hosts" // ES >= 7.X
 
+ ReadinessPort = "readiness.port" // ES >= 8.2.0
+
  NetworkHost = "network.host"
  NetworkPublishHost = "network.publish_host"
  HTTPPublishHost = "http.publish_host"

pkg/controller/elasticsearch/configmap/configmap.go

@@ -53,11 +53,12 @@ func ReconcileScriptsConfigMap(ctx context.Context, c k8s.Client, es esv1.Elasti
  types.NamespacedName{Namespace: es.Namespace, Name: esv1.ScriptsConfigMap(es.Name)},
  k8s.ExtractNamespacedName(&es),
  map[string]string{
- nodespec.ReadinessProbeScriptConfigKey: nodespec.ReadinessProbeScript,
- nodespec.PreStopHookScriptConfigKey: preStopScript,
- initcontainer.PrepareFsScriptConfigKey: fsScript,
- initcontainer.SuspendScriptConfigKey: initcontainer.SuspendScript,
- initcontainer.SuspendedHostsFile: initcontainer.RenderSuspendConfiguration(es),
+ nodespec.ReadinessProbeScriptConfigKey: nodespec.ReadinessProbeScript,
+ nodespec.ReadinessPortProbeScriptConfigKey: nodespec.ReadinessPortProbeScript,
+ nodespec.PreStopHookScriptConfigKey: preStopScript,
+ initcontainer.PrepareFsScriptConfigKey: fsScript,
+ initcontainer.SuspendScriptConfigKey: initcontainer.SuspendScript,
+ initcontainer.SuspendedHostsFile: initcontainer.RenderSuspendConfiguration(es),
  },
  )
 

pkg/controller/elasticsearch/nodespec/podspec.go

@@ -127,7 +127,7 @@ func BuildPodTemplateSpec(
  WithResources(DefaultResources).
  WithTerminationGracePeriod(DefaultTerminationGracePeriodSeconds).
  WithPorts(defaultContainerPorts).
- WithReadinessProbe(*NewReadinessProbe()).
+ WithReadinessProbe(*NewReadinessProbe(v)).
  WithAffinity(DefaultAffinity(es.Name)).
  WithEnv(DefaultEnvVars(es.Spec.HTTP, headlessServiceName)...).
  WithVolumes(volumes...).

pkg/controller/elasticsearch/nodespec/podspec_test.go

@@ -362,7 +362,7 @@ func TestBuildPodTemplateSpec(t *testing.T) {
  DefaultEnvVars(sampleES.Spec.HTTP, HeadlessServiceName(esv1.StatefulSet(sampleES.Name, nodeSet.Name)))...),
  Resources: DefaultResources,
  VolumeMounts: volumeMounts,
- ReadinessProbe: NewReadinessProbe(),
+ ReadinessProbe: NewReadinessProbe(ver),
  Lifecycle: &corev1.Lifecycle{
  PreStop: NewPreStopHook(),
  },

pkg/controller/elasticsearch/nodespec/readiness_probe.go

@@ -9,12 +9,30 @@ import (
 
  corev1 "k8s.io/api/core/v1"
 
+ esv1 "github.com/elastic/cloud-on-k8s/v2/pkg/apis/elasticsearch/v1"
  "github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/http"
+ "github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/version"
  "github.com/elastic/cloud-on-k8s/v2/pkg/controller/elasticsearch/label"
  "github.com/elastic/cloud-on-k8s/v2/pkg/controller/elasticsearch/volume"
 )
 
-func NewReadinessProbe() *corev1.Probe {
+// as of 8.2.0 a simplified unauthenticated readiness port is available which takes cluster membership into account
+// see https://www.elastic.co/guide/en/elasticsearch/reference/current/advanced-configuration.html#readiness-tcp-port
+
+const (
+ ReadinessPortProbeScriptConfigKey = "readiness-port-script.sh"
+ // ReadinessPortProbeScript is the simplified readiness check for ES >= 8.2.0 which supports a dedicated TCP check
+ ReadinessPortProbeScript = `#!/usr/bin/env bash
+nc -z -v -w5 127.0.0.1 8080
+`
+)
+
+func NewReadinessProbe(v version.Version) *corev1.Probe {
+ scriptKey := ReadinessPortProbeScriptConfigKey
+ if v.LE(esv1.MinReadinessPortVersion) {
+ scriptKey = ReadinessProbeScriptConfigKey
+ }
+
  return &corev1.Probe{
  FailureThreshold: 3,
  InitialDelaySeconds: 10,
@@ -23,7 +41,7 @@ func NewReadinessProbe() *corev1.Probe {
  TimeoutSeconds: 5,
  ProbeHandler: corev1.ProbeHandler{
  Exec: &corev1.ExecAction{
- Command: []string{"bash", "-c", path.Join(volume.ScriptsVolumeMountPath, ReadinessProbeScriptConfigKey)},
+ Command: []string{"bash", "-c", path.Join(volume.ScriptsVolumeMountPath, scriptKey)},
  },
  },
  }

pkg/controller/elasticsearch/settings/merged_config.go

@@ -83,6 +83,10 @@ func baseConfig(clusterName string, ver version.Version, ipFamily corev1.IPFamil
  cfg[esv1.DiscoverySeedHosts] = []string{}
  }
 
+ if ver.GTE(esv1.MinReadinessPortVersion) {
+ cfg[esv1.ReadinessPort] = "8080"
+ }
+
  return &CanonicalConfig{common.MustCanonicalConfig(cfg)}
 }
 

pkg/controller/elasticsearch/settings/merged_config_test.go

@@ -181,6 +181,24 @@ func TestNewMergedESConfig(t *testing.T) {
  require.Equal(t, 1, len(cfg.HasKeys([]string{esv1.XPackLicenseUploadTypes})))
  },
  },
+ {
+ name: "prior to 8.2.0 we should not enable the readiness.port",
+ version: "8.1.0",
+ ipFamily: corev1.IPv4Protocol,
+ cfgData: map[string]interface{}{},
+ assert: func(cfg CanonicalConfig) {
+ require.Equal(t, 0, len(cfg.HasKeys([]string{esv1.ReadinessPort})))
+ },
+ },
+ {
+ name: "starting 8.2.0 we should enable the readiness.port",
+ version: "8.2.0",
+ ipFamily: corev1.IPv4Protocol,
+ cfgData: map[string]interface{}{},
+ assert: func(cfg CanonicalConfig) {
+ require.Equal(t, 1, len(cfg.HasKeys([]string{esv1.ReadinessPort})))
+ },
+ },
  {
  name: "user-provided Elasticsearch config overrides should have precedence over ECK config",
  version: "7.6.0",