feat(Traefik Proxy): support NativeLB option in GatewayAPI provider

Author: mloiseleur

traefik/VALUES.md

@@ -259,6 +259,7 @@ Kubernetes: `>=1.22.0-0`
 | providers.kubernetesGateway.experimentalChannel | bool | `false` | Toggles support for the Experimental Channel resources (Gateway API release channels documentation). This option currently enables support for TCPRoute and TLSRoute. |
 | providers.kubernetesGateway.labelselector | string | `""` | A label selector can be defined to filter on specific GatewayClass objects only. |
 | providers.kubernetesGateway.namespaces | list | `[]` | Array of namespaces to watch. If left empty, Traefik watches all namespaces. |
+| providers.kubernetesGateway.nativeLBByDefault | bool | `false` | Defines whether to use Native Kubernetes load-balancing mode by default. |
 | providers.kubernetesGateway.statusAddress.hostname | string | `""` | This Hostname will get copied to the Gateway status.addresses. |
 | providers.kubernetesGateway.statusAddress.ip | string | `""` | This IP will get copied to the Gateway status.addresses, and currently only supports one IP value (IPv4 or IPv6). |
 | providers.kubernetesGateway.statusAddress.service | object | `{"name":"{{ (include \"traefik.fullname\" .) }}","namespace":"{{ .Release.Namespace }}"}` | The Kubernetes service to copy status addresses from. When using third parties tools like External-DNS, this option can be used to copy the service loadbalancer.status (containing the service's endpoints IPs) to the gateways. Default to Service of this Chart. |

traefik/templates/_podtemplate.tpl

@@ -533,6 +533,9 @@
           - "--providers.kubernetesgateway.statusaddress.service.namespace={{ tpl .namespace $ }}"
              {{- end }}
             {{- end }}
+            {{- if .nativeLBByDefault }}
+          - "--providers.kubernetesgateway.nativeLBByDefault=true"
+            {{- end }}
             {{- if or .namespaces (and $.Values.rbac.enabled $.Values.rbac.namespaced) }}
           - "--providers.kubernetesgateway.namespaces={{ template "providers.kubernetesGateway.namespaces" $ }}"
             {{- end }}

traefik/templates/requirements.yaml

@@ -35,3 +35,7 @@
 {{- if and (semverCompare "<v3.3.0-0" $version) (.Values.experimental.abortOnPluginFailure)}}
   {{- fail "ERROR: abortOnPluginFailure is an experimental feature only available for traefik >= v3.3.0." }}
 {{- end }}
+
+{{- if and (semverCompare "<3.2.0-0" $version) (.Values.providers.kubernetesGateway.nativeLBByDefault)}}
+  {{- fail "ERROR: nativeLBByDefault has been introduced in Kubernetes Gateway provider in v3.2.0" }}
+{{- end }}

traefik/tests/requirements-config_test.yaml

@@ -43,6 +43,17 @@ tests:
     asserts:
       - failedTemplate:
           errorMessage: "ERROR: Before traefik v3.1.0-rc3, kubernetesGateway is experimental. Enable it by setting experimental.kubernetesGateway.enabled to true"
+  - it: should fail when using nativeLBByDefault on kubernetesGateway on traefik < 3.2
+    set:
+      image:
+        tag: v3.1.0
+      providers:
+        kubernetesGateway:
+          enabled: true
+          nativeLBByDefault: true
+    asserts:
+      - failedTemplate:
+          errorMessage: "ERROR: nativeLBByDefault has been introduced in Kubernetes Gateway provider in v3.2.0"
   - it: should not fail when using kubernetesGateway on traefik > 3.1.0-rc3 without experimental flag
     set:
       image:

traefik/tests/traefik-config_test.yaml

@@ -706,6 +706,7 @@ tests:
         kubernetesGateway:
           enabled: true
           experimentalChannel: true
+          nativeLBByDefault: true
           labelselector: "app=traefik"
     asserts:
       - contains:
@@ -714,6 +715,9 @@ tests:
       - contains:
           path: spec.template.spec.containers[0].args
           content: "--providers.kubernetesgateway.labelselector=app=traefik"
+      - contains:
+          path: spec.template.spec.containers[0].args
+          content: "--providers.kubernetesgateway.nativeLBByDefault=true"
   - it: should be possible to allow ACME bypass
     set:
       ports:

traefik/values.schema.json

@@ -1357,6 +1357,9 @@
                         "namespaces": {
                             "type": "array"
                         },
+                        "nativeLBByDefault": {
+                            "type": "boolean"
+                        },
                         "statusAddress": {
                             "properties": {
                                 "hostname": {

traefik/values.yaml

@@ -305,6 +305,8 @@ providers:  # @schema additionalProperties: false
     namespaces: []
     # -- A label selector can be defined to filter on specific GatewayClass objects only.
     labelselector: ""
+    # -- Defines whether to use Native Kubernetes load-balancing mode by default.
+    nativeLBByDefault: false
     statusAddress:
       # -- This IP will get copied to the Gateway status.addresses, and currently only supports one IP value (IPv4 or IPv6).
       ip: ""