cert-manager-webhook-domeneshop

cert-manager-webhook-domeneshop

This is a DNS01 webhook implementation for cert-manager, allowing usage of the Domeneshop API to issue certificates for wildcard domains or other names that are not publicly accessible.

This repository is based on the cert-manager-webhook-example repository provided by Jetstack.

Usage

Requirements

• Working cert-manager deployed in your Kubernetes cluster
• An API key for the Domeneshop API
• A domain configured to use DNS service with Domeneshop

Installing

1. Create a Kubernetes namespace for the webhook to live in

   kubectl create ns webhook-domeneshop
   

2. Install the Helm chart

   helm install webhook --set groupName='api.domeneshop.no' --namespace=webhook-domeneshop deploy/domeneshop-webhook
   

3. Ensure the pod is running

   % kubectl get pods -n webhook-domeneshop
   NAME                                                       READY   STATUS    RESTARTS   AGE
   webhook-cert-manager-webhook-domeneshop-7745d84f75-qrlsk   1/1     Running   0          108s
   

Issuer and secrets

In order to issue certificates using the webhook, create a new Issuer resource with cert-manager.

Ensure the email address is set to a valid address, and that the groupName matches the name passed in step #2 above.

apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
  name: domeneshop-dns01
spec:
  acme:
    email: example@example.com
    server: https://acme-v02.api.letsencrypt.org/directory
    privateKeySecretRef:
      name: letsencrypt-account-key
    solvers:
    - dns01:
        webhook:
          groupName: api.domeneshop.no
          solverName: domeneshop
          config:
            APITokenSecretRef:
              key: APIToken
              name: domeneshop-credentials
            APISecretSecretRef:
              key: APISecret
              name: domeneshop-credentials

Finally, create the corresponding secret containing your Domeneshop API credentials:

kubectl create secret generic domeneshop-credentials \
    --namespace webhook-domeneshop \
    --from-literal=APIToken=<token> \
    --from-literal=APISecret=<secret>

NOTE: If your cluster is RBAC-enabled and you want to use a ClusterIssuer instead, you may have to uncomment the bottom two resources in deploy/domeneshop-webhook/templates/rbac.yaml before installing the Helm chart, in order for the webhook to read the credentials secrets in the cert-manager namespace.

Issue a certificate

You should now be ready to issue certificate using DNS01 challenges through the Domeneshop API!

apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
  name: test-certificate
spec:
  dnsNames:
  - www.example.com
  issuerRef:
    name: domeneshop-dns01
    kind: Issuer
  secretName: test-certificate-tls

Eventually, the certificate should be issued using the webhook:

% kubectl get certificate
NAME                                                  READY   SECRET                                                AGE
test-certificate                                      True    test-certificate-tls                                  3m36s

For troubleshooting, try using kubectl describe on the resources related to the issuance (e.g. certificates.acme.cert-manager.io, challenges.acme.cert-manager.io, orders.acme.cert-manager.io). Refer to the cert-manager documentation for more information.

Running tests

1. Download required testing binaries:

   make test/kubebuilder
   

2. Edit testdata/domeneshop-webhook/secret.yml with a valid API token and secret.

3. Run the tests (replace example.com. with the FQDN for a domain on your account):

   TEST_ZONE_NAME=example.com. go test -v .
   

   NOTE: The tests will create and validate TXT records on your domain.