feat(helm): allow skipping IngressClass creation (#3979)

Signed-off-by: EndlessSeeker <1766508902@qq.com>

helm/core/templates/ingressclass.yaml

@@ -1,4 +1,4 @@
-{{- if .Values.global.ingressClass }}
+{{- if and .Values.global.ingressClass .Values.global.createIngressClass }}
 apiVersion: networking.k8s.io/v1
 kind: IngressClass
 metadata:

helm/core/values.yaml

@@ -25,6 +25,9 @@ global:
   # 2. When the ingress class is set empty, the higress controller will watch all ingress
   # resources in the k8s cluster.
   ingressClass: "higress"
+  # -- Whether to create the IngressClass resource for global.ingressClass.
+  # Set this to false when reusing an existing IngressClass, for example during Nginx Ingress migration.
+  createIngressClass: true
   # -- If not empty, Higress Controller will only watch resources in the specified namespace.
   # When isolating different business systems using K8s namespace,
   # if each namespace requires a standalone gateway instance,

helm/higress/README.md

@@ -161,6 +161,7 @@ The command removes all the Kubernetes components associated with the chart and
 | global.caAddress | string | `""` | The customized CA address to retrieve certificates for the pods in the cluster. CSR clients such as the Istio Agent and ingress gateways can use this to specify the CA endpoint. If not set explicitly, default to the Istio discovery address. |
 | global.caName | string | `""` | The name of the CA for workload certificates. For example, when caName=GkeWorkloadCertificate, GKE workload certificates will be used as the certificates for workloads. The default value is "" and when caName="", the CA will be configured by other mechanisms (e.g., environmental variable CA_PROVIDER). |
 | global.configCluster | bool | `false` | Configure a remote cluster as the config cluster for an external istiod. |
+| global.createIngressClass | bool | `true` | Whether to create the IngressClass resource for global.ingressClass. Set this to false when reusing an existing IngressClass, for example during Nginx Ingress migration. |
 | global.defaultPodDisruptionBudget | object | `{"enabled":false}` | enable pod disruption budget for the control plane, which is used to ensure Istio control plane components are gradually upgraded or recovered. |
 | global.defaultResources | object | `{"requests":{"cpu":"10m"}}` | A minimal set of requested resources to applied to all deployments so that Horizontal Pod Autoscaler will be able to function (if set). Each component can overwrite these default values by adding its own resources block in the relevant section below and setting the desired resources values. |
 | global.defaultUpstreamConcurrencyThreshold | int | `10000` |  |

helm/higress/README.zh.md

@@ -145,6 +145,7 @@ helm delete higress -n higress-system
 | gateway.service.ports[1].protocol | string | `"TCP"` | 协议 |
 | gateway.service.ports[1].targetPort | int | `443` | 靶向端口 |
 | gateway.service.type | string | `"LoadBalancer"` | 服务类型 |
+| global.createIngressClass | bool | `true` | 是否为 global.ingressClass 创建 IngressClass 资源。复用已有 IngressClass 时可设置为 false，例如从 Nginx Ingress 迁移场景。 |
 | global.disableAlpnH2 | bool | `false` | 设置是否禁用 ALPN 中的 http/2 |
 | global.enableAlphaGatewayAPI | bool | `false` | 是否监听 alpha 阶段的 Gateway API 资源 |
 | global.enableInferenceExtension | bool | `false` | 是否启用 Gateway API Inference Extension 支持 |