Require Multiple Replicas in CEL expressions

 1apiVersion: kyverno.io/v1
 2kind: ClusterPolicy
 3metadata:
 4  name: deployment-has-multiple-replicas
 5  annotations:
 6    policies.kyverno.io/title: Require Multiple Replicas in CEL expressions
 7    policies.kyverno.io/category: Sample in CEL 
 8    policies.kyverno.io/severity: medium
 9    policies.kyverno.io/subject: Deployment
10    policies.kyverno.io/minversion: 1.11.0
11    kyverno.io/kubernetes-version: "1.26-1.27"
12    policies.kyverno.io/description: >-
13      Deployments with a single replica cannot be highly available and thus the application
14      may suffer downtime if that one replica goes down. This policy validates that Deployments
15      have more than one replica.
16spec:
17  validationFailureAction: Audit
18  background: true
19  rules:
20    - name: deployment-has-multiple-replicas
21      match:
22        any:
23        - resources:
24            kinds:
25            - Deployment
26            operations:
27            - CREATE
28            - UPDATE
29      validate:
30        cel:
31          expressions:
32            - expression: "object.spec.replicas > 1"
33              message: "Deployments should have more than one replica to ensure availability."