cert-manager CPanel DNS Webhook

A simple webhook DNS solver for cert-manager using the CPanel UAPI for those of us stuck using their webhost's CPanel for DNS.

This is based off the example webhook.

Getting started

1. Install cert-manager. This was developed when running v1.8 but it should work reasonably across versions. This is assumed to be in the cert-manager namespace, if not you'll need to tweak the Helm values.
2. Install this webhook. There's a Helm chart in deploy/chart (helm install cpanel-webhook .), or kubectl apply -f https://raw.githubusercontent.com/jamesorlakin/cert-manager-cpanel-dns-webhook/master/deploy/v0.3.0.yaml will install this in the cert-manager namespace.
3. Create a secret containing your CPanel credentials.

   apiVersion: v1
   kind: Secret
   type: Opaque
   metadata:
     name: some-cpanel-credentials
     namespace: cert-manager
   stringData:
     username: my-cpanel-user
     password: my-cpanel-password
     # Or, instead of a password in v0.2.0+, create and use an API token from CPanel's Security section:
     apiToken: ABCDEF1234567890ABCDEFABCDEF1234567890

4. Create an ACME issuer referencing the webhook, e.g.:

   apiVersion: cert-manager.io/v1
   kind: ClusterIssuer
   metadata:
     name: letsencrypt-staging
   spec:
     acme:
       server: https://acme-staging-v02.api.letsencrypt.org/directory
       email: my-acme-email@yourself.com
       privateKeySecretRef:
         name: letsencrypt-staging
       solvers:
       - dns01:
           # The fun bit:
           webhook:
             groupName: jameslakin.co.uk # Must match the group name in the Helm chart (this is the default and shouldn't need changing to your own domain)
             solverName: cpanel-solver # Don't change
             config:
               cpanelUrl: https://cpanel.my-super-website.com # No trailing slash
               secretRef: cert-manager/some-cpanel-credentials # In the form namespace/secret-name

5. ...issue certificates:

   apiVersion: cert-manager.io/v1
   kind: Certificate
   metadata:
     name: example-cpanel-cert
   spec:
     secretName: example-cpanel-cert
     issuerRef:
       name: letsencrypt-staging
       kind: ClusterIssuer
     dnsNames:
     - '*.whatever.my-super-website.com'