Add update updateStrategy and minReadySeconds for defaultBackend (#8506)

* Add update updateStrategy and minReadySeconds for defaultBackend

* Bump chart

* Fixed docs helm-docs version

charts/ingress-nginx/README.md

@@ -481,6 +481,7 @@ Kubernetes: `>=1.20.0-0`
 | defaultBackend.livenessProbe.successThreshold | int | `1` |  |
 | defaultBackend.livenessProbe.timeoutSeconds | int | `5` |  |
 | defaultBackend.minAvailable | int | `1` |  |
+| defaultBackend.minReadySeconds | int | `0` | `minReadySeconds` to avoid killing pods before we are ready # |
 | defaultBackend.name | string | `"defaultbackend"` |  |
 | defaultBackend.nodeSelector | object | `{"kubernetes.io/os":"linux"}` | Node labels for default backend pod assignment # Ref: https://kubernetes.io/docs/user-guide/node-selection/ # |
 | defaultBackend.podAnnotations | object | `{}` | Annotations to be added to default backend pods # |
@@ -504,6 +505,7 @@ Kubernetes: `>=1.20.0-0`
 | defaultBackend.serviceAccount.create | bool | `true` |  |
 | defaultBackend.serviceAccount.name | string | `""` |  |
 | defaultBackend.tolerations | list | `[]` | Node tolerations for server scheduling to nodes with taints # Ref: https://kubernetes.io/docs/concepts/configuration/assign-pod-node/ # |
+| defaultBackend.updateStrategy | object | `{}` | The update strategy to apply to the Deployment or DaemonSet # |
 | dhParam | string | `nil` | A base64-encoded Diffie-Hellman parameter. This can be generated with: `openssl dhparam 4096 2> /dev/null | base64` # Ref: https://github.com/kubernetes/ingress-nginx/tree/main/docs/examples/customization/ssl-dh-param |
 | imagePullSecrets | list | `[]` | Optional array of imagePullSecrets containing private registry credentials # Ref: https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/ |
 | podSecurityPolicy.enabled | bool | `false` |  |

charts/ingress-nginx/templates/default-backend-deployment.yaml

@@ -19,6 +19,11 @@ spec:
   replicas: {{ .Values.defaultBackend.replicaCount }}
 {{- end }}
   revisionHistoryLimit: {{ .Values.revisionHistoryLimit }}
+  {{- if .Values.defaultBackend.updateStrategy }}
+  strategy:
+    {{ toYaml .Values.defaultBackend.updateStrategy | nindent 4 }}
+  {{- end }}
+  minReadySeconds: {{ .Values.defaultBackend.minReadySeconds }}
   template:
     metadata:
     {{- if .Values.defaultBackend.podAnnotations }}

charts/ingress-nginx/values.yaml

@@ -841,6 +841,17 @@ defaultBackend:
     successThreshold: 1
     timeoutSeconds: 5
 
+  # -- The update strategy to apply to the Deployment or DaemonSet
+  ##
+  updateStrategy: {}
+  #  rollingUpdate:
+  #    maxUnavailable: 1
+  #  type: RollingUpdate
+
+  # -- `minReadySeconds` to avoid killing pods before we are ready
+  ##
+  minReadySeconds: 0
+
   # -- Node tolerations for server scheduling to nodes with taints
   ## Ref: https://kubernetes.io/docs/concepts/configuration/assign-pod-node/
   ##