Header based session persistence cannot be configured without AbsoluteTimeout

[sanposhiho]

What happened:

Header based session persistence cannot be configured without AbsoluteTimeout.

If you apply -

apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: envoy-header-based-session-persistence
  namespace: gateway-conformance-infra
spec:
  parentRefs:
    - name: same-namespace
  rules:
    - matches:
        - path:
            type: PathPrefix
            value: /
      backendRefs:
        - name: infra-backend-v1
          port: 8080
        - name: infra-backend-v2
          port: 8080
      sessionPersistence:
        sessionName: session-a
        type: Header

it hits the validation issue:

AbsoluteTimeout must be specified when cookie lifetimeType is Permanent

What you expected to happen:

Header based session persistence shouldn't have CookieConfig, and it should be allowed Header based session persistence not to have AbsoluteTimeout.

How to reproduce it (as minimally and precisely as possible):

Just apply -

apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: envoy-header-based-session-persistence
  namespace: gateway-conformance-infra
spec:
  parentRefs:
    - name: same-namespace
  rules:
    - matches:
        - path:
            type: PathPrefix
            value: /
      backendRefs:
        - name: infra-backend-v1
          port: 8080
        - name: infra-backend-v2
          port: 8080
      sessionPersistence:
        sessionName: session-a
        type: Header

Anything else we need to know?:

[gauravkghildiyal]

Thanks for catching this @sanposhiho