GKE Ingress requires pathType to be ImplementationSpecific

[tvories]

Overview of the Issue

In a GKE cluster, when attempting to use GKE ingress, we are receiving an error:

4m Warning Translate ingress/consul-consul-ingress Translation failed: invalid ingress spec: only "ImplementationSpecific" path type is supported

According to Google, for ingress to work properly, pathType needs to be set to ImplementationSpecific. In the ui-ingress.yaml template, the value is hardcoded to prefix.

Reproduction Steps

1. When running helm install with the following values.yml:

ui:
      ingress:
        annotations: | # https://cloud.google.com/kubernetes-engine/docs/how-to/load-balance-ingress#ingress_annotations
          kubernetes.io/ingress.class: gce
          kubernetes.io/ingress.global-static-ip-name: ${google_compute_global_address.consul.name}
          networking.gke.io/v1beta1.FrontendConfig: ${helm_release.consul_gcp_ingress_configs.name}
        enabled: true
        hosts:
          - host: ${trimsuffix(google_dns_record_set.consul.name, ".")}
            paths:
              - /* # Google wants /* instead of /
        tls:
          - hosts:
            - consul.example.com
            secretName: ${kubernetes_secret.consul_pki.metadata.0.name}

1. View error

4m Warning Translate ingress/consul-consul-ingress Translation failed: invalid ingress spec: only "ImplementationSpecific" path type is supported

Expected behavior

Values.yaml should allow someone to override default pathType to whichever type they need.

Environment details

If not already included, please provide the following:

• consul-k8s version: 1.19.10-gke.1600
• consul-helm version: 0.31.1

Additionally, please provide details regarding the Kubernetes Infrastructure, if known:

• Cloud Provider (If self-hosted, the Kubernetes provider utilized): GKE