# API for certificate renewal in KCP

### Option 1

kind: KubeadmControlPlaneTemplate
apiVersion: controlplane.cluster.x-k8s.io/v1beta1
metadata:
  name: "kcp-name"
spec:
  rolloutIfCertificatesExpireWithinDays: 21 # 3 weeks
  rolloutBefore:
    certificatesExpiryDays: 21 # minimum of 7d
  rolloutAfter: "2020-01-01T00:00:00Z"
  rolloutStrategy:
    type: rollingUpdate
    rollingUpdate: 
      maxSurge: 1
    

Other alternatives for the field name:
* RolloutBeforeCertificatesExpireDays
* RolloutDaysBeforeCertificatesExpire
* RolloutIfCertificatesExpireInDays
* RolloutIfCertificatesExpireAfterDays
* RolloutIfCertificatesExpiryDurationBelowDays
* RolloutIfCertificatesExpiryWithinDays

### Option 2
**Start Here in `v1beta1`:**

kind: KubeadmControlPlaneTemplate
apiVersion: controlplane.cluster.x-k8s.io/v1beta1
metadata:
  name: "kcp-name"
spec:
    rolloutAfter: "2020-01-01T00:00:00Z"
    rolloutStrategy:
      type: rollingUpdate
      rollingUpdate: 
        maxSurge: 1
    rollout:
       if:
          certificateExpireWithinDays: 21 # 3 weeks

**Get here in `v1beta2`:**

kind: KubeadmControlPlaneTemplate
apiVersion: controlplane.cluster.x-k8s.io/v1beta1
metadata:
  name: "kcp-name"
spec:
    rollout:
       if:
          certificateExpireWithinDays:
          timeGreaterThan: # This is equivalent to rollout after (or better names)
        strategy:
          type: rollingUpdate
          rollingUpdate: 
            maxSurge: 1
          # ... everything else (in-the-future strategies) can sit here

### Option 3