[feat:gwapi] Add context-aware TargetGroupConfiguration and LoadBalancerConfiguration CRDs for Gateway API

[shraddhabang]

Description

This commit implements a new context-aware TargetGroupConfiguration mechanism for the Gateway API. We are introducing a new Namespace scoped TargetGroupConfiguration CRD which will give more granular control over Target group properties for the tgs provisioned for Gateway API resources. It adds a RouteConfiguration map to the TargetGroupConfiguration CRD, enabling users to define Target Group properties specific to individual routes. Users can use the same map to define the default configuration for the routes using "::" as route name to provide fallback configuration. A longest-prefix matching algorithm will be implemented to resolve the correct TargetGroupDefinition based on the route name (KIND:NAME:NAMESPACE).

This change addresses limitations in the previous approach taken by the controller in Ingress/Service resources, enhancing service reusability and providing granular control over Target Group properties.

Example CRD looks like this

apiVersion: gateway.k8s.aws/v1beta1
kind: TargetGroupConfiguration
metadata:
  name: test-tg-config
  namespace: example-ns
spec:
  targetReference:
    name: "game-2048"
  routeConfigurations:
    - name: "::example-ns"
      targetGroupProps:
        vpcID: "vpc-23467812w"
        ipAddressType: "ipv4"
        tags:
          - key: "hello"
            value: "world"
        targetGroupAttributes:
          - key: "deregistration_delay.timeout_seconds"
            value: "30"
          - key: "slow_start.duration_seconds"
            value: "30"
    - name: "TCPRoute:tcproute1:example-ns"
      targetGroupProps:
        targetType: "ip"
        healthCheckConfig:
          healthyThresholdCount: 5
          healthCheckInterval: 34
          healthCheckPath: "/healthz-tcp"
          healthCheckPort: 443
          healthCheckProtocol: "tcp"
          healthCheckTimeout: 110
          unhealthyThresholdCount: 2
          matcher:
            httpCode: "200"
    - name: "HTTPRoute:httproute1:example-ns"
      targetGroupProps:
        targetType: "instance"
        protocolVersion: "grpc"
        healthCheckConfig:
          healthyThresholdCount: 6
          healthCheckInterval: 56
          healthCheckPath: "/healthz-http"
          healthCheckPort: 80
          healthCheckProtocol: "http"
          healthCheckTimeout: 90
          unhealthyThresholdCount: 3
          matcher:
            grpcCode: "80"
        nodeSelector:
          matchExpressions:
            - key: "k2"
              operator: "o2"

Notes: All the target groups provisioned for the routes in example-ns namespace for the service specified in targetReference will by default have vpcID, IpAddressType, Tags and TargetGroupAttributes values specified in route section named "::example-ns". The specific tg properties will be applied to specific tgs provisioned for Routes defined in CRD.

As this feature is currently under development, this PR also adds this new CRD to separate directory to keep our existing IngressClassParams and TargetGroupBinding CRDs segregated.

The LoadBalancerConfiguration CRD is added for configuration load balancer config at a granular level for both GatewayClass and Gateways.

Example:

apiVersion: gateway.k8s.aws/v1beta1
kind: LoadBalancerConfiguration
metadata:
  name: lb-config-test
  namespace: my-ns
spec:
  loadBalancerName: my-loadbalancer
  ipAddressType: ipv4
  scheme: internal
  securityGroups: [sg-xxxx, nameOfSg1, nameOfSg2]
  loadBalancerSubnets:
    - identifier: subnet-1234
      eipAllocation: eipalloc-xyz
      privateIPv4Allocation: 128.98.76.8
    - identifier: subnet-4567
      eipAllocation: eipalloc-abc
  listenerConfigurations:
    - protocolPort: 'HTTPS:443'
      defaultCertificate: arn:aws:acm:us-east-1:123456789:certificate/test-arn-1
      certificates: ['arn:aws:acm:us-east-1:123456789:certificate/test-arn-2','arn:aws:acm:us-east-1:123456789:certificate/test-arn-3']
      listenerAttributes:
        - key: routing.http.response.server.enabled
          value: "true"
    - protocolPort: 'HTTPS:8080'
      defaultCertificate: arn:aws:acm:us-east-1:123456789:certificate/test-arn-2
      certificates: [ 'arn:aws:acm:us-east-1:123456789:certificate/test-arn-5','arn:aws:acm:us-east-1:123456789:certificate/test-arn-4' ]
  loadBalancerAttributes:
    - key: deletion_protection.enabled
      value: 'true'
    - key: idle_timeout.timeout_seconds
      value: '120'

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: shraddhabang

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[zac-nixon]

Probably should drop the ExternalName blurb as it's not applicable to our use-case. We just want the CRD to attach to a service.

[shraddhabang]

Done.

[zac-nixon]

/lgtm

[zac-nixon]

note for later: this should be added to the kubebuilder validation

[zac-nixon]

I realized that it might be tricky to track this status when the config is shared among many gateways :x lets think about this some more

[k8s-ci-robot]

New changes are detected. LGTM label has been removed.