apiVersion: templates.gatekeeper.sh/v1
kind: ConstraintTemplate
metadata:
  name: k8sdeniedservicetypes
spec:
  crd:
    spec:
      names:
        kind: K8sDeniedServiceTypes
      validation:
        openAPIV3Schema:
          type: object
          properties:
            deniedTypes:
              type: array
              items:
                type: string
  targets:
    - target: admission.k8s.gatekeeper.sh
      rego: |
        package d8.pod_security_standards.extended

        violation[{"msg": msg}] {
          service := input.review.object
          service.kind == "Service"
          denied := service.spec.type
          denied == "NodePort"
          msg := sprintf("Service type %v is not allowed.", [denied])
        }

        violation[{"msg": msg}] {
          service := input.review.object
          service.kind == "Service"
          denied := service.spec.type
          denied == "LoadBalancer"
          msg := sprintf("Service type %v is not allowed.", [denied])
        }

        violation[{"msg": msg}] {
          service := input.review.object
          service.kind == "Service"
          externalIPs := service.spec.externalIPs
          count(externalIPs) > 0
          msg := "Usage of externalIPs is not allowed."
        }