Add HorizontalPodAutoScaler Processor

examples/app/templates/hpa.yaml

@@ -0,0 +1,14 @@
+apiVersion: autoscaling/v1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "app.fullname" . }}-hpa
+  labels:
+  {{- include "app.labels" . | nindent 4 }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: myapp
+  minReplicas: {{ .Values.hpa.minReplicas }}
+  maxReplicas: {{ .Values.hpa.maxReplicas }}
+  targetCPUUtilizationPercentage: {{ .Values.hpa.targetCPUUtilizationPercentage }}

examples/app/values.yaml

@@ -22,6 +22,10 @@ fluentdElasticsearch:
       requests:
         cpu: 100m
         memory: 200Mi
+hpa:
+  maxReplicas: 10
+  minReplicas: 2
+  targetCPUUtilizationPercentage: 80
 kubernetesClusterDomain: cluster.local
 myConfig:
   dummyconfigmapkey: dummyconfigmapvalue

examples/operator/templates/app-hpa.yaml

@@ -0,0 +1,14 @@
+apiVersion: autoscaling/v1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "operator.fullname" . }}-app-hpa
+  labels:
+  {{- include "operator.labels" . | nindent 4 }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: myapp
+  minReplicas: {{ .Values.appHpa.minReplicas }}
+  maxReplicas: {{ .Values.appHpa.maxReplicas }}
+  targetCPUUtilizationPercentage: {{ .Values.appHpa.targetCPUUtilizationPercentage }}

examples/operator/values.yaml

@@ -1,3 +1,7 @@
+appHpa:
+  maxReplicas: 10
+  minReplicas: 2
+  targetCPUUtilizationPercentage: 80
 configmapVars:
   var4: value for var4
 controllerManager:

pkg/app/app.go

@@ -8,6 +8,7 @@ import (
 	"syscall"
 
 	"github.com/arttor/helmify/pkg/file"
+	"github.com/arttor/helmify/pkg/processor/horizontalpodautoscaler"
 	"github.com/arttor/helmify/pkg/processor/job"
 	"github.com/arttor/helmify/pkg/processor/poddisruptionbudget"
 	"github.com/arttor/helmify/pkg/processor/statefulset"
@@ -67,6 +68,7 @@ func Start(stdin io.Reader, config config.Config) error {
 		job.NewCron(),
 		job.NewJob(),
 		poddisruptionbudget.New(),
+		horizontalpodautoscaler.New(),
 	).WithDefaultProcessor(processor.Default())
 	if len(config.Files) != 0 {
 		file.Walk(config.Files, config.FilesRecursively, func(filename string, fileReader io.Reader) {

pkg/processor/horizontalpodautoscaler/hpa.go

@@ -0,0 +1,117 @@
+package horizontalpodautoscaler
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+
+	"github.com/arttor/helmify/pkg/processor"
+
+	"github.com/arttor/helmify/pkg/helmify"
+	yamlformat "github.com/arttor/helmify/pkg/yaml"
+	"github.com/iancoleman/strcase"
+	autoscalingv1 "k8s.io/api/autoscaling/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"sigs.k8s.io/yaml"
+)
+
+const (
+	hpaTempSpec = `
+spec:
+  scaleTargetRef:
+%[1]s
+  minReplicas: {{ .Values.%[2]s.minReplicas }}
+  maxReplicas: {{ .Values.%[2]s.maxReplicas }}
+  targetCPUUtilizationPercentage: {{ .Values.%[2]s.targetCPUUtilizationPercentage }}`
+)
+
+var hpaGVC = schema.GroupVersionKind{
+	Group:   "autoscaling",
+	Version: "v1",
+	Kind:    "HorizontalPodAutoscaler",
+}
+
+// New creates processor for k8s Service resource.
+func New() helmify.Processor {
+	return &hpa{}
+}
+
+type hpa struct{}
+
+// Process k8s Service object into template. Returns false if not capable of processing given resource type.
+func (r hpa) Process(appMeta helmify.AppMetadata, obj *unstructured.Unstructured) (bool, helmify.Template, error) {
+	if obj.GroupVersionKind() != hpaGVC {
+		return false, nil, nil
+	}
+	hpa := autoscalingv1.HorizontalPodAutoscaler{}
+	err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.Object, &hpa)
+	if err != nil {
+		return true, nil, fmt.Errorf("%w: unable to cast to hpa", err)
+	}
+	spec := hpa.Spec
+	values := helmify.Values{}
+
+	meta, err := processor.ProcessObjMeta(appMeta, obj)
+	if err != nil {
+		return true, nil, err
+	}
+
+	name := appMeta.TrimName(obj.GetName())
+	nameCamel := strcase.ToLowerCamel(name)
+
+	scaleTargetRef, err := yaml.Marshal(hpa.Spec.ScaleTargetRef)
+	if err != nil {
+		return true, nil, fmt.Errorf("error marshaling scaleTargetRef: %w", err)
+	}
+	scaleTargetRef = yamlformat.Indent(scaleTargetRef, 4)
+	scaleTargetRef = bytes.TrimRight(scaleTargetRef, "\n ")
+
+	if spec.MinReplicas != nil && *spec.MinReplicas != 0 {
+		_, err := values.Add(*spec.MinReplicas, nameCamel, "minReplicas")
+		if err != nil {
+			return true, nil, err
+		}
+	}
+
+	if spec.MaxReplicas != 0 {
+		_, err := values.Add(spec.MaxReplicas, nameCamel, "maxReplicas")
+		if err != nil {
+			return true, nil, err
+		}
+	}
+
+	if spec.TargetCPUUtilizationPercentage != nil && *spec.TargetCPUUtilizationPercentage != 0 {
+		_, err := values.Add(*spec.TargetCPUUtilizationPercentage, nameCamel, "targetCPUUtilizationPercentage")
+		if err != nil {
+			return true, nil, err
+		}
+	}
+
+	res := meta + fmt.Sprintf(hpaTempSpec, scaleTargetRef, nameCamel)
+	return true, &result{
+		name:   name,
+		data:   res,
+		values: values,
+	}, nil
+}
+
+type result struct {
+	name   string
+	data   string
+	values helmify.Values
+}
+
+func (r *result) Filename() string {
+	return r.name + ".yaml"
+}
+
+func (r *result) Values() helmify.Values {
+	return r.values
+}
+
+func (r *result) Write(writer io.Writer) error {
+	_, err := writer.Write([]byte(r.data))
+	return err
+}

pkg/processor/horizontalpodautoscaler/hpa_test.go

@@ -0,0 +1,42 @@
+package horizontalpodautoscaler
+
+import (
+	"os"
+	"testing"
+
+	"github.com/arttor/helmify/pkg/metadata"
+
+	"github.com/arttor/helmify/internal"
+	"github.com/stretchr/testify/assert"
+)
+
+const hpaYaml = `apiVersion: autoscaling/v1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: myapp-hpa
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: myapp
+  minReplicas: 2
+  maxReplicas: 10
+  targetCPUUtilizationPercentage: 80`
+
+func Test_hpa_Process(t *testing.T) {
+	var testInstance hpa
+
+	t.Run("processed", func(t *testing.T) {
+		obj := internal.GenerateObj(hpaYaml)
+		processed, tt, err := testInstance.Process(&metadata.Service{}, obj)
+		_ = tt.Write(os.Stdout)
+		assert.NoError(t, err)
+		assert.Equal(t, true, processed)
+	})
+	t.Run("skipped", func(t *testing.T) {
+		obj := internal.TestNs
+		processed, _, err := testInstance.Process(&metadata.Service{}, obj)
+		assert.NoError(t, err)
+		assert.Equal(t, false, processed)
+	})
+}

test_data/k8s-operator-kustomize.output

@@ -846,3 +846,16 @@ webhooks:
     resources:
     - myclusters
   sideEffects: None
+---
+apiVersion: autoscaling/v1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: myapp-hpa
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: myapp
+  minReplicas: 2
+  maxReplicas: 10
+  targetCPUUtilizationPercentage: 80

test_data/sample-app.yaml

@@ -375,3 +375,16 @@ spec:
   selector:
     matchLabels:
       app: nginx
+---
+apiVersion: autoscaling/v1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: myapp-hpa
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: myapp
+  minReplicas: 2
+  maxReplicas: 10
+  targetCPUUtilizationPercentage: 80