add horizontalpodautoscaler (#3276)

Co-authored-by: Shaun <[email protected]>

Author: coolbry95

deployments/helm-chart/README.md

@@ -248,6 +248,12 @@ Parameter | Description | Default
 `controller.readyStatus.initialDelaySeconds` | The number of seconds after the Ingress Controller pod has started before readiness probes are initiated. | 0
 `controller.enableLatencyMetrics` | Enable collection of latency metrics for upstreams. Requires `prometheus.create`. | false
 `controller.minReadySeconds` | Specifies the minimum number of seconds for which a newly created Pod should be ready without any of its containers crashing, for it to be considered available. [docs](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#min-ready-seconds) | 0
+`controller.autoscaling.enabled` | Enables HorizontalPodAutoscaling. | false
+`controller.autoscaling.annotations` | The annotations of the Ingress Controller HorizontalPodAutoscaler. | {}
+`controller.autoscaling.minReplicas` | Minimum number of replicas for the HPA. | 1
+`controller.autoscaling.maxReplicas` | Maximum number of replicas for the HPA. | 3
+`controller.autoscaling.targetCPUUtilizationPercentage` | The target CPU utilization percentage. | 50
+`controller.autoscaling.targetMemoryUtilizationPercentage` | The target memory utilization percentage. | 50
 `controller.strategy` | Specifies the strategy used to replace old Pods by new ones. [docs](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#strategy) | {}
 `controller.disableIPV6` | Disable IPV6 listeners explicitly for nodes that do not support the IPV6 stack. | false
 `rbac.create` | Configures RBAC. | true

deployments/helm-chart/templates/controller-hpa.yaml

@@ -0,0 +1,37 @@
+{{- if and .Values.controller.autoscaling.enabled (eq .Values.controller.kind "deployment") (semverCompare ">=1.23.0" .Capabilities.KubeVersion.Version) -}}
+apiVersion: autoscaling/v2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "nginx-ingress.serviceName" . }}
+  namespace: {{ .Release.Namespace }}
+  labels:
+    {{- include "nginx-ingress.labels" . | nindent 4 }}
+{{- if .Values.controller.autoscaling.annotations }}
+  annotations:
+{{ toYaml .Values.controller.autoscaling.annotations | indent 4 }}
+{{- end }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: {{ default (include "nginx-ingress.name" .) .Values.controller.name }}
+  minReplicas: {{ .Values.controller.autoscaling.minReplicas }}
+  maxReplicas: {{ .Values.controller.autoscaling.maxReplicas }}
+  metrics:
+    {{- if .Values.controller.autoscaling.targetCPUUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: cpu
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.controller.autoscaling.targetCPUUtilizationPercentage }}
+    {{- end }}
+    {{- if .Values.controller.autoscaling.targetMemoryUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: memory
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.controller.autoscaling.targetMemoryUtilizationPercentage }}
+    {{- end }}
+{{- end }}

deployments/helm-chart/values.yaml

@@ -119,6 +119,21 @@ controller:
   ## The termination grace period of the Ingress Controller pod.
   terminationGracePeriodSeconds: 30
 
+  ## HorizontalPodAutoscaling (HPA)
+  autoscaling:
+    ## Enables HorizontalPodAutoscaling.
+    enabled: false
+    ## The annotations of the Ingress Controller HorizontalPodAutoscaler.
+    annotations: {}
+    ## Minimum number of replicas for the HPA.
+    minReplicas: 1
+    ## Maximum number of replicas for the HPA.
+    maxReplicas: 3
+    ## The target cpu utilization percentage.
+    targetCPUUtilizationPercentage: 50
+    ## The target memory utilization percentage.
+    targetMemoryUtilizationPercentage: 50
+
   ## The resources of the Ingress Controller pods.
   resources:
     requests:

docs/content/installation/installation-with-helm.md

@@ -236,6 +236,12 @@ The following tables lists the configurable parameters of the NGINX Ingress Cont
 |``controller.readyStatus.initialDelaySeconds`` | The number of seconds after the Ingress Controller pod has started before readiness probes are initiated. | 0 |
 |``controller.enableLatencyMetrics`` | Enable collection of latency metrics for upstreams. Requires ``prometheus.create``. | false |
 |``controller.minReadySeconds`` | Specifies the minimum number of seconds for which a newly created Pod should be ready, without any of its containers crashing, for it to be considered available. [docs](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#min-ready-seconds) | 0 |
+|``controller.autoscaling.enabled`` | Enables HorizontalPodAutoscaling. | false |
+|``controller.autoscaling.annotations`` | The annotations of the Ingress Controller HorizontalPodAutoscaler. | {} |
+|``controller.autoscaling.minReplicas`` | Minimum number of replicas for the HPA. | 1 |
+|``controller.autoscaling.maxReplicas`` | Maximum number of replicas for the HPA. | 3 |
+|``controller.autoscaling.targetCPUUtilizationPercentage`` | The target CPU utilization percentage. | 50 |
+|``controller.autoscaling.targetMemoryUtilizationPercentage`` | The target memory utilization percentage. | 50 |
 |``controller.strategy`` | Specifies the strategy used to replace old Pods with new ones. [docs](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/#strategy) | {} |
 | `controller.disableIPV6` | Disable IPV6 listeners explicitly for nodes that do not support the IPV6 stack. | false |
 |``rbac.create`` | Configures RBAC. | true |