Add ipFamily-related options

[hrntknr]

Add support for ipFamilyPolicy,ipFamilies.
ref: https://kubernetes.io/docs/concepts/services-networking/dual-stack/

The actual output of yaml when values are not specified is as follows.

$ helm install minecraft oci://**********/library/minecraft --dry-run --debug
(omit)
---
# Source: minecraft/templates/minecraft-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: minecraft-minecraft
  labels:
    app: minecraft-minecraft
    chart: "minecraft-4.9.4"
    release: "minecraft"
    heritage: "Helm"
    app.kubernetes.io/name: "minecraft"
    app.kubernetes.io/instance: minecraft-minecraft
    app.kubernetes.io/version: "4.9.4"
  annotations:
    {}
spec:
  type: ClusterIP
  ports:
  - name: minecraft
    port: 25565
    targetPort: minecraft
    protocol: TCP
  selector:
    app: minecraft-minecraft

ipFamilyPolicy,ipFamilies can be specified as follows

helm install minecraft oci://**********/library/minecraft --dry-run --debug --values helm/minecraft/server01.yaml
(omit)
# Source: minecraft/templates/minecraft-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: minecraft-minecraft
  labels:
    app: minecraft-minecraft
    chart: "minecraft-4.9.4"
    release: "minecraft"
    heritage: "Helm"
    app.kubernetes.io/name: "minecraft"
    app.kubernetes.io/instance: minecraft-minecraft
    app.kubernetes.io/version: "4.9.4"
  annotations:
    {}
spec:
  type: LoadBalancer
  ipFamilyPolicy: RequireDualStack
  ipFamilies:
    - IPv4
    - IPv6
  ports:
  - name: minecraft
    port: 25565
    targetPort: minecraft
    protocol: TCP
  selector:
    app: minecraft-minecraft

[hrntknr]

I set PreferDualStack as the default policy, the yaml without the value would be as follows.

# Source: minecraft/templates/minecraft-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: minecraft-minecraft
  labels:
    app: minecraft-minecraft
    chart: "minecraft-4.9.5"
    release: "minecraft"
    heritage: "Helm"
    app.kubernetes.io/name: "minecraft"
    app.kubernetes.io/instance: minecraft-minecraft
    app.kubernetes.io/version: "4.9.5"
  annotations:
    {}
spec:
  type: ClusterIP
  ipFamilyPolicy: PreferDualStack
  ports:
  - name: minecraft
    port: 25565
    targetPort: minecraft
    protocol: TCP
  selector:
    app: minecraft-minecraft

[itzg]

Thanks for the contribution. I'm wondering if this should be more generalized to something like extraServiceSpec which is an object value that'll get "appended" into the spec. My worry is that the values gradually become a flattened representation of the entire kubernetes data model.

Admittedly the risk is that a user will include a colliding field in the extra fields, but that'll fail early at validation/deploy.

[hrntknr]

Thanks for the review.
You are right, it would be better to make it more generalized as extraServiceSpec.
We will implement and propose extraServiceSpec in another PR.