Add ability to configure network protocol and load balancer class for external service configs

[mh013370]

Q	A
Bug fix?	no
New feature?	yes
API breaks?	no
Deprecations?	no
Related tickets	fixes #331
License	Apache 2.0

What's in this PR?

Adds the ability to set the network protocol for external services. Defaults to TCP and behaves almost identically to the recent addition to support this for internal listeners in #320.

It also adds the ability to set the loadBalancerClass for external services. This is useful when using cloud based load balancers.

Example:

  externalServices:
    - name: "clusterip"
      spec:
        type: ClusterIP
        portConfigs:
          - port: 8080
            internalListenerName: "http"
          - port: 7182
            internalListenerName: "my-custom-listener"
            protocol: TCP
      metadata:
        annotations:
          toto: tata
        labels:
          titi: tutu

And to set a loadBalancerClass:

externalServices:
    - name: "nlb"
      spec:
        type: LoadBalancer
        loadBalancerClass: "service.k8s.aws/nlb"
        portConfigs:
          - port: 8080
            internalListenerName: "http"
          - port: 7182
            internalListenerName: "my-custom-listener"
            protocol: TCP
      metadata:
        annotations:
          toto: tata
        labels:
          titi: tutu

Why?

It's possible to set the network protocol for container ports but not for services, so this just completes the feature.

Checklist

• Implementation tested
• Error handling code meets the guideline
• Logging code meets the guideline
• User guide and development docs updated (if needed)
• Append changelog with changes

[juldrixx]

Can you add in the example loadBalancerClass as you did for protocol?

[mh013370]

Can you add in the example loadBalancerClass as you did for protocol?

In the docs? Surely!