chore: add Helm Chart

Dockerfile

@@ -7,4 +7,4 @@ RUN pip install -r requirements.txt
 
 COPY main.py main.py
 
-CMD ["python", "main.py"]
+ENTRYPOINT ["python", "main.py"]

README.md

@@ -16,8 +16,12 @@ or
 
 `python main.py --help`
 
+Needs Python `>=3.10`
+
 ### Deploy
 
 Docker images are published [here](https://hub.docker.com/r/machine424/kube-hpa-scale-to-zero).
 
-A Helm chart is also available [here](). (Coming soon)
+A Helm chart is also available [here](./helm-chart).
+
+`helm upgrade --install RELEASE_NAME helm-chart/ -n RELEASE_NAMESPACE`

helm-chart/.helmignore

@@ -0,0 +1,23 @@
+# Patterns to ignore when building packages.
+# This supports shell glob matching, relative path matching, and
+# negation (prefixed with !). Only one pattern per line.
+.DS_Store
+# Common VCS dirs
+.git/
+.gitignore
+.bzr/
+.bzrignore
+.hg/
+.hgignore
+.svn/
+# Common backup files
+*.swp
+*.bak
+*.tmp
+*.orig
+*~
+# Various IDEs
+.project
+.idea/
+*.tmproj
+.vscode/

helm-chart/Chart.yaml

@@ -0,0 +1,6 @@
+apiVersion: v2
+name: kube-hpa-scale-to-zero
+description: See https://github.com/machine424/kube-hpa-scale-to-zero
+type: application
+version: 0.2.0
+appVersion: "0.2.0"

helm-chart/templates/_helpers.tpl

@@ -0,0 +1,62 @@
+{{/*
+Expand the name of the chart.
+*/}}
+{{- define "kube-hpa-scale-to-zero.name" -}}
+{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Create a default fully qualified app name.
+We truncate at 63 chars because some Kubernetes name fields are limited to this (by the DNS naming spec).
+If release name contains chart name it will be used as a full name.
+*/}}
+{{- define "kube-hpa-scale-to-zero.fullname" -}}
+{{- if .Values.fullnameOverride }}
+{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- $name := default .Chart.Name .Values.nameOverride }}
+{{- if contains $name .Release.Name }}
+{{- .Release.Name | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }}
+{{- end }}
+{{- end }}
+{{- end }}
+
+{{/*
+Create chart name and version as used by the chart label.
+*/}}
+{{- define "kube-hpa-scale-to-zero.chart" -}}
+{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Common labels
+*/}}
+{{- define "kube-hpa-scale-to-zero.labels" -}}
+helm.sh/chart: {{ include "kube-hpa-scale-to-zero.chart" . }}
+{{ include "kube-hpa-scale-to-zero.selectorLabels" . }}
+{{- if .Chart.AppVersion }}
+app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+{{- end }}
+app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end }}
+
+{{/*
+Selector labels
+*/}}
+{{- define "kube-hpa-scale-to-zero.selectorLabels" -}}
+app.kubernetes.io/name: {{ include "kube-hpa-scale-to-zero.name" . }}
+app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end }}
+
+{{/*
+Create the name of the service account to use
+*/}}
+{{- define "kube-hpa-scale-to-zero.serviceAccountName" -}}
+{{- if .Values.rbac.create }}
+{{- default (include "kube-hpa-scale-to-zero.fullname" .) .Values.rbac.serviceAccountName }}
+{{- else }}
+{{- default "default" .Values.rbac.serviceAccountName }}
+{{- end }}
+{{- end }}

helm-chart/templates/deployment.yaml

@@ -0,0 +1,39 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "kube-hpa-scale-to-zero.fullname" . }}
+  labels:
+    {{- include "kube-hpa-scale-to-zero.labels" . | nindent 4 }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  selector:
+    matchLabels:
+      {{- include "kube-hpa-scale-to-zero.selectorLabels" . | nindent 6 }}
+  template:
+    metadata:
+      {{- with .Values.podAnnotations }}
+      annotations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      labels:
+        {{- include "kube-hpa-scale-to-zero.selectorLabels" . | nindent 8 }}
+    spec:
+      serviceAccountName: {{ include "kube-hpa-scale-to-zero.serviceAccountName" . }}
+      containers:
+        - name: {{ .Chart.Name }}
+          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          {{- with .Values.args }}
+          args:
+            {{- toYaml . | nindent 12 }}
+          {{- end }}
+          resources:
+            {{- toYaml .Values.resources | nindent 12 }}
+      {{- with .Values.affinity }}
+      affinity:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.tolerations }}
+      tolerations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}

helm-chart/templates/rbac.yaml

@@ -0,0 +1,46 @@
+{{- if .Values.rbac.create -}}
+
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  name: {{ include "kube-hpa-scale-to-zero.serviceAccountName" . }}
+  labels:
+    {{- include "kube-hpa-scale-to-zero.labels" . | nindent 4 }}
+rules:
+  - apiGroups: ["apps"]
+    resources: ["deployments/scale"]
+    verbs: ["get", "patch"]
+  - apiGroups: ["autoscaling"]
+    resources: ["horizontalpodautoscalers"]
+    verbs: ["get", "list", "watch"]
+  - apiGroups: ["custom.metrics.k8s.io"]
+    resources: ["*"]
+    verbs: ["get"]
+
+
+---
+
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: {{ include "kube-hpa-scale-to-zero.serviceAccountName" . }}
+  labels:
+    {{- include "kube-hpa-scale-to-zero.labels" . | nindent 4 }}
+subjects:
+  - kind: ServiceAccount
+    name: {{ include "kube-hpa-scale-to-zero.serviceAccountName" . }}
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: Role
+  name: {{ include "kube-hpa-scale-to-zero.serviceAccountName" . }}
+
+---
+
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: {{ include "kube-hpa-scale-to-zero.serviceAccountName" . }}
+  labels:
+    {{- include "kube-hpa-scale-to-zero.labels" . | nindent 4 }}
+
+{{- end }}

helm-chart/values.yaml

@@ -0,0 +1,24 @@
+replicaCount: 1
+
+image:
+  repository: machine424/kube-hpa-scale-to-zero
+  pullPolicy: IfNotPresent
+  tag: "0.2.0"
+
+nameOverride: ""
+fullnameOverride: ""
+
+# args: ["--hpa-namespace", "foo"]
+args: []
+
+rbac:
+  create: true
+  serviceAccountName: ""
+
+podAnnotations: {}
+
+resources: {}
+
+tolerations: []
+
+affinity: {}

main.py

@@ -16,23 +16,6 @@
 )
 LOGGER = logging.getLogger(__name__)
 
-parser = argparse.ArgumentParser(
-    description="kube-hpa-scale-to-zero. Check https://github.com/machine424/kube-hpa-scale-to-zero"
-)
-parser.add_argument(
-    "--hpa-label-selector",
-    dest="hpa_label_selector",
-    default="",
-    help="label_selector to get HPA to watch, 'foo=bar,bar=foo' e.g. (default: empty string to select all)",
-)
-parser.add_argument(
-    "--hpa-namespace",
-    dest="hpa_namespace",
-    default="default",
-    help="namespace where the HPA live. (default: 'default' namespace)",
-)
-ARGS = parser.parse_args()
-
 
 def load_kubernetes_config() -> None:
     try:
@@ -73,17 +56,17 @@ def _watch():
     threading.Thread(target=_watch, daemon=True).start()
 
 
-def watch_hpa() -> None:
+def watch_hpa(args) -> None:
     LOGGER.info(
-        f"Will watch HPA with label selector '{ARGS.hpa_label_selector}' in {ARGS.hpa_namespace}."
+        f"Will watch HPA with label selector '{args.hpa_label_selector}' in {args.hpa_namespace}."
     )
     while True:
         try:
             w = watch.Watch()
             for event in w.stream(
                 AUTOSCALING_V1.list_namespaced_horizontal_pod_autoscaler,
-                ARGS.hpa_namespace,
-                label_selector=ARGS.hpa_label_selector,
+                args.hpa_namespace,
+                label_selector=args.hpa_label_selector,
             ):
                 update_hpa(event["object"].metadata)
         except kubernetes.client.exceptions.ApiException as exc:
@@ -207,6 +190,27 @@ def update_deployment(*, namespace, name, needed_replicas) -> None:
         raise exc
 
 
+def parse_cli_args():
+    parser = argparse.ArgumentParser(
+        description="kube-hpa-scale-to-zero. Check https://github.com/machine424/kube-hpa-scale-to-zero"
+    )
+    parser.add_argument(
+        "--hpa-namespace",
+        dest="hpa_namespace",
+        default="default",
+        help="namespace where the HPA live. (default: 'default' namespace)",
+    )
+    parser.add_argument(
+        "--hpa-label-selector",
+        dest="hpa_label_selector",
+        default="",
+        help="label_selector to get HPA to watch, 'foo=bar,bar=foo' e.g. (default: empty string to select all)",
+    )
+
+    return parser.parse_args()
+
+
 if __name__ == "__main__":
+    cli_args = parse_cli_args()
     watch_metrics()
-    watch_hpa()
+    watch_hpa(cli_args)