Refactor stack monitoring templating

pkg/controller/beat/common/pod.go

@@ -164,7 +164,7 @@ func buildPodTemplate(
 	}
 
 	if monitoring.IsMetricsDefined(&params.Beat) {
-		sideCar, err := beat_stackmon.MetricBeat(params.Context, params.Client, &params.Beat, params.Beat.Spec.Version)
+		sideCar, err := beat_stackmon.MetricBeat(params.Context, params.Client, &params.Beat)
 		if err != nil {
 			return podTemplate, err
 		}

pkg/controller/beat/common/stackmon/stackmon.go

@@ -5,22 +5,19 @@
 package stackmon
 
 import (
-	"bytes"
 	"context"
 	_ "embed" // for the beats config files
 	"errors"
 	"fmt"
-	"text/template"
 
 	corev1 "k8s.io/api/core/v1"
 
 	"github.com/elastic/cloud-on-k8s/v2/pkg/apis/beat/v1beta1"
-	commonv1 "github.com/elastic/cloud-on-k8s/v2/pkg/apis/common/v1"
 	esv1 "github.com/elastic/cloud-on-k8s/v2/pkg/apis/elasticsearch/v1"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/association"
-	common_name "github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/name"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/stackmon"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/stackmon/monitoring"
+	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/version"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/elasticsearch/bootstrap"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/utils/k8s"
 )
@@ -60,7 +57,7 @@ func Filebeat(ctx context.Context, client k8s.Client, resource monitoring.HasMon
 	return sidecar, nil
 }
 
-func MetricBeat(ctx context.Context, client k8s.Client, beat *v1beta1.Beat, version string) (stackmon.BeatSidecar, error) {
+func MetricBeat(ctx context.Context, client k8s.Client, beat *v1beta1.Beat) (stackmon.BeatSidecar, error) {
 	if err := beat.ElasticsearchRef().IsValid(); err != nil {
 		return stackmon.BeatSidecar{}, err
 	}
@@ -70,11 +67,6 @@ func MetricBeat(ctx context.Context, client k8s.Client, beat *v1beta1.Beat, vers
 		return stackmon.BeatSidecar{}, err
 	}
 
-	beatTemplate, err := template.New("beat_stack_monitoring").Parse(metricbeatConfigTemplate)
-	if err != nil {
-		return stackmon.BeatSidecar{}, fmt.Errorf("while parsing template for beats stack monitoring configuration: %w", err)
-	}
-	var byteBuffer bytes.Buffer
 	data := struct {
 		ClusterUUID string
 		URL         string
@@ -84,24 +76,16 @@ func MetricBeat(ctx context.Context, client k8s.Client, beat *v1beta1.Beat, vers
 		// Beat module http options require "http+" to be appended to unix sockets.
 		URL: fmt.Sprintf("http+%s", GetStackMonitoringSocketURL(beat)),
 	}
-	if err := beatTemplate.Execute(&byteBuffer, data); err != nil {
-		return stackmon.BeatSidecar{}, fmt.Errorf("while templating beats stack monitoring configuration: %w", err)
+	v, err := version.Parse(beat.Spec.Version)
+	if err != nil {
+		return stackmon.BeatSidecar{}, err
+	}
+	cfg, err := stackmon.RenderTemplate(v, metricbeatConfigTemplate, data)
+	if err != nil {
+		return stackmon.BeatSidecar{}, err
 	}
 
-	sidecar, err := stackmon.NewMetricBeatSidecar(
-		ctx,
-		client,
-		commonv1.BeatMonitoringAssociationType,
-		beat,
-		version,
-		byteBuffer.String(),
-		common_name.NewNamer("beat"),
-		GetStackMonitoringSocketURL(beat),
-		"",
-		"",
-		"",
-		false,
-	)
+	sidecar, err := stackmon.NewMetricBeatSidecar(ctx, client, beat, v, nil, cfg)
 	if err != nil {
 		return stackmon.BeatSidecar{}, err
 	}

pkg/controller/beat/common/stackmon/stackmon_test.go

@@ -250,9 +250,8 @@ output:
 	}
 
 	type args struct {
-		client  k8s.Client
-		beat    func() *v1beta1.Beat
-		version string
+		client k8s.Client
+		beat   func() *v1beta1.Beat
 	}
 	tests := []struct {
 		name    string
@@ -270,7 +269,6 @@ output:
 				beat: func() *v1beta1.Beat {
 					return &beatFixture
 				},
-				version: "8.2.3",
 			},
 			want:    beatSidecarFixture(fmt.Sprintf(beatYml, "abcd1234", "es-metrics-monitoring-url")),
 			wantErr: false,
@@ -287,7 +285,6 @@ output:
 					beat.Spec.ElasticsearchRef = commonv1.ObjectSelector{}
 					return beat
 				},
-				version: "8.2.3",
 			},
 			want:    beatSidecarFixture(standaloneBeatYML),
 			wantErr: false,
@@ -317,7 +314,6 @@ output:
 					}
 					return beat
 				},
-				version: "8.2.3",
 			},
 			want:    beatSidecarFixture(fmt.Sprintf(beatYml, "QGq3wcU7Sd6bC31wh37eKQ", esAPIFixture.URL)),
 			wantErr: false,
@@ -331,15 +327,14 @@ output:
 					beat.Spec.Config.Data = map[string]interface{}{"http.port": "invalid"}
 					return beat
 				},
-				version: "8.2.3",
 			},
 			want:    stackmon.BeatSidecar{},
 			wantErr: true,
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := MetricBeat(context.Background(), tt.args.client, tt.args.beat(), tt.args.version)
+			got, err := MetricBeat(context.Background(), tt.args.client, tt.args.beat())
 			if (err != nil) != tt.wantErr {
 				t.Errorf("MetricBeat() error = %v, wantErr %v", err, tt.wantErr)
 				return

pkg/controller/common/stackmon/config.go

@@ -17,12 +17,10 @@ import (
 	"github.com/pkg/errors"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/types"
 
 	commonv1 "github.com/elastic/cloud-on-k8s/v2/pkg/apis/common/v1"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/association"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/certificates"
-	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/name"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/settings"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/stackmon/monitoring"
 	"github.com/elastic/cloud-on-k8s/v2/pkg/controller/common/volume"
@@ -165,87 +163,32 @@ func mergeConfig(rawConfig string, config map[string]interface{}) ([]byte, error
 	return cfgBytes, nil
 }
 
-// inputConfigData holds data to configure the Metricbeat Elasticsearch and Kibana modules used
-// to collect metrics for Stack Monitoring
-type inputConfigData struct {
-	BasePath         string
-	URL              string
-	Username         string
-	Password         string
-	IsSSL            bool
-	HasCA            bool
-	CAPath           string
-	Version          semver.Version
-	TotalFieldsLimit int
+func RenderTemplate(v semver.Version, configTemplate string, params any) (string, error) {
+	// render the config template with the config data
+	var beatConfig bytes.Buffer
+	err := template.Must(template.New("").Funcs(TemplateFuncs(v)).Parse(configTemplate)).Execute(&beatConfig, params)
+	if err != nil {
+		return "", err
+	}
+	return beatConfig.String(), nil
 }
 
-// buildMetricbeatBaseConfig builds the base configuration for Metricbeat with the Elasticsearch or Kibana modules used
-// to collect metrics for Stack Monitoring
-func buildMetricbeatBaseConfig(
-	client k8s.Client,
-	associationType commonv1.AssociationType,
-	nsn types.NamespacedName,
-	namer name.Namer,
-	url string,
-	basePath string,
-	username string,
-	password string,
-	isTLS bool,
-	configTemplate string,
+func TemplateFuncs(
 	version semver.Version,
-) (string, volume.VolumeLike, error) {
-	hasCA := false
-	if isTLS {
-		var err error
-		hasCA, err = certificates.PublicCertsHasCACert(client, namer, nsn.Namespace, nsn.Name)
-		if err != nil {
-			return "", nil, err
-		}
-	}
-
-	configData := inputConfigData{
-		Username: username,
-		Password: password,
-		URL:      url,      // Metricbeat in the sidecar connects to the monitored resource using `localhost`
-		BasePath: basePath, // for the Metricbeat Kibana module
-		IsSSL:    isTLS,    // enable SSL configuration based on whether the monitored resource has TLS enabled
-		HasCA:    hasCA,    // the CA is optional to support custom certificate issued by a well-known CA, so without provided CA to configure
-		Version:  version,  // Version of the monitored resource
-	}
-
-	// See https://github.com/elastic/cloud-on-k8s/pull/8284
-	// The default index template for metricbeat exceeds the default
-	// index mapping total fields limit.
-	if version.GTE(semver.MustParse("8.15.0")) {
-		configData.TotalFieldsLimit = 12500
-	}
-
-	var caVolume volume.VolumeLike
-	if configData.HasCA {
-		caVolume = volume.NewSecretVolumeWithMountPath(
-			certificates.PublicCertsSecretName(namer, nsn.Name),
-			fmt.Sprintf("%s-local-ca", string(associationType)),
-			fmt.Sprintf("/mnt/elastic-internal/%s/%s/%s/certs", string(associationType), nsn.Namespace, nsn.Name),
-		)
-
-		configData.CAPath = filepath.Join(caVolume.VolumeMount().MountPath, certificates.CAFileName)
-	}
-
-	templateFuncMap := template.FuncMap{
+) template.FuncMap {
+	return template.FuncMap{
 		"isVersionGTE": func(minAllowedVersion string) (bool, error) {
 			minAllowedSemver, err := semver.Parse(minAllowedVersion)
 			if err != nil {
 				return false, err
 			}
 			return version.GTE(minAllowedSemver), nil
 		},
+		"CAPath": func(caVolume volume.VolumeLike) string {
+			if caVolume == nil {
+				return ""
+			}
+			return filepath.Join(caVolume.VolumeMount().MountPath, certificates.CAFileName)
+		},
 	}
-	// render the config template with the config data
-	var metricbeatConfig bytes.Buffer
-	err := template.Must(template.New("").Funcs(templateFuncMap).Parse(configTemplate)).Execute(&metricbeatConfig, configData)
-	if err != nil {
-		return "", nil, err
-	}
-
-	return metricbeatConfig.String(), caVolume, nil
 }