apiVersion: gateway.networking.k8s.io/v1alpha2
kind: GatewayClass
metadata:
  name: istio
spec:
  controllerName: istio.io/gateway-controller
---
apiVersion: gateway.networking.k8s.io/v1alpha2
kind: Gateway
metadata:
  name: third-party-gateway
  namespace: istio-system
spec:
  addresses:
  - value: istio-ingressgateway
    type: Hostname
  gatewayClassName: third-party-gatewayclass
  listeners:
  - name: default
    hostname: "*.domain.example"
    port: 80
    protocol: HTTP
    allowedRoutes:
      namespaces:
        from: All
---
apiVersion: gateway.networking.k8s.io/v1alpha2
kind: Gateway
metadata:
  name: gateway
  namespace: istio-system
  annotations:
    gateway.istio.io/alias-for: third-party-gateway
spec:
  addresses:
  - value: istio-ingressgateway
    type: Hostname
  gatewayClassName: istio
  listeners:
  - name: default
    hostname: "*.domain.example"
    port: 80
    protocol: HTTP
    allowedRoutes:
      namespaces:
        from: All
---
apiVersion: gateway.networking.k8s.io/v1alpha2
kind: HTTPRoute
metadata:
  name: http
  namespace: default
spec:
  parentRefs:
  - name: third-party-gateway
    namespace: istio-system
  hostnames: ["first.domain.example", "another.domain.example"]
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /
    backendRefs:
    - name: httpbin
      port: 80
