firezone-gateway: support autoscaling (#28)

* firezone-gateway: support autoscaling

* firezone-gateway: bump version

firezone-gateway/Chart.yaml

@@ -1,7 +1,7 @@
 apiVersion: v2
 name: firezone-gateway
-version: 0.10.0
-appVersion: "1.1.1"
+version: 0.11.0
+appVersion: "1.1.2"
 type: application
 description: A Helm chart for deploying a firezone gateway
 icon: https://raw.githubusercontent.com/firezone/firezone/main/website/public/images/logo-main.svg

firezone-gateway/templates/deployment.yaml

@@ -5,7 +5,9 @@ metadata:
   labels:
     {{- include "firezone-gateway.labels" . | nindent 4 }}
 spec:
+  {{- if not .Values.autoscaling.enabled }}
   replicas: {{ .Values.replicas }}
+  {{- end }}
   revisionHistoryLimit: {{ .Values.revisionHistoryLimit }}
   selector:
     matchLabels:

firezone-gateway/templates/hpa.yaml

@@ -0,0 +1,32 @@
+{{- if .Values.autoscaling.enabled }}
+apiVersion: autoscaling/v2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "firezone-gateway.fullname" . }}
+  labels:
+    {{- include "firezone-gateway.labels" . | nindent 4 }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name:  {{ include "firezone-gateway.fullname" . }}
+  minReplicas: {{ .Values.autoscaling.minReplicas }}
+  maxReplicas: {{ .Values.autoscaling.maxReplicas }}
+  metrics:
+    {{- if .Values.autoscaling.targetCPUUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: cpu
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }}
+    {{- end }}
+    {{- if .Values.autoscaling.targetMemoryUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: memory
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetMemoryUtilizationPercentage }}
+    {{- end }}
+{{- end }}

firezone-gateway/templates/pdb.yml

@@ -0,0 +1,24 @@
+{{- if .Values.pdb.enabled }}
+apiVersion: policy/v1
+kind: PodDisruptionBudget
+metadata:
+  name: {{ include "firezone-gateway.fullname" . }}
+  labels:
+    {{- include "firezone-gateway.labels" . | nindent 4 }}
+    {{- with .Values.pdb.labels }}
+      {{- toYaml . | nindent 4 }}
+    {{- end }}
+  {{ with .Values.pdb.annotations }}
+  annotations:
+    {{- toYaml . | nindent 4 }}
+  {{- end }}
+spec:
+  {{- with .Values.pdb.maxUnavailable }}
+  maxUnavailable: {{ . }}
+  {{- else }}
+  minAvailable: {{ .Values.pdb.minAvailable | default 0 }}
+  {{- end }}
+  selector:
+    matchLabels:
+      {{- include "firezone-gateway.selectorLabels" . | nindent 6 }}
+{{- end }}

firezone-gateway/values.yaml

@@ -59,3 +59,17 @@ serviceAccount:
   # The name of the service account to use.
   # If not set and create is true, a name is generated using the fullname template
   name: ""
+
+autoscaling:
+  enabled: false
+  minReplicas: 1
+  maxReplicas: 100
+  targetCPUUtilizationPercentage: 80
+  # targetMemoryUtilizationPercentage: 80
+
+pdb:
+  enabled: false
+  labels: {}
+  annotations: {}
+  minAvailable: ""
+  maxUnavailable: ""