Prevent Bare Pods

apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: prevent-bare-pods
  annotations:
    policies.kyverno.io/title: Prevent Bare Pods
    pod-policies.kyverno.io/autogen-controllers: none
    policies.kyverno.io/category: Other, EKS Best Practices
    policies.kyverno.io/severity: medium
    kyverno.io/kyverno-version: 1.7.0
    policies.kyverno.io/minversion: 1.6.0
    kyverno.io/kubernetes-version: "1.23"
    policies.kyverno.io/subject: Pod
    policies.kyverno.io/description: Pods not created by workload controllers such as Deployments have no self-healing or scaling abilities and are unsuitable for production. This policy prevents such "bare" Pods from being created unless they originate from a higher-level workload controller of some sort.
spec:
  validationFailureAction: Audit
  background: true
  rules:
    - name: bare-pods
      match:
        any:
          - resources:
              kinds:
                - Pod
      preconditions:
        all:
          - key: "{{request.operation || 'BACKGROUND'}}"
            operator: NotEquals
            value: DELETE
      validate:
        message: Bare Pods are not allowed. They must be created by Pod controllers.
        deny:
          conditions:
            any:
              - key: ownerReferences
                operator: AnyNotIn
                value: "{{request.object.metadata.keys(@)}}"