apiVersion: kyverno.io/v1alpha1
kind: Policy
metadata:
  name: check-cpu-memory
spec:
  rules:
  - name: check-pod-resources
    match:
      resources:
        kinds:
        - Pod
    validate:
      message: "CPU and memory resource requests and limits are required"
      pattern:
        spec:
          containers:
          # 'name: *' selects all containers in the pod
          - name: "*"
            resources:
              limits:
                # '?' requires 1 alphanumeric character and '*' means that there can be 0 or more characters.
                # Using them together e.g. '?*' requires at least one character. 
                memory: "?*"
                cpu: "?*"
              requests:
                memory: "?*"
                cpu: "?*"