kubebuilder debug web-hooks locally - go

Question

We have a kubebuilder controller which is working as expected, now we need to create a webhooks ,
I follow the tutorial
https://book.kubebuilder.io/reference/markers/webhook.html
and now I want to run & debug it locally,
however not sure what to do regard the certificate, is there a simple way to create it , any example will be very helpful.
BTW i've installed cert-manager and apply the following sample yaml but not sure what to do next ...
I need the simplest solution that I be able to run and debug the webhooks locally as Im doing already with the controller (Before using webhooks),
https://book.kubebuilder.io/cronjob-tutorial/running.html
Cert-manager
I've created the following inside my cluster
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: example-com
namespace: test
spec:
# Secret names are always required.
secretName: example-com-tls
# secretTemplate is optional. If set, these annotations and labels will be
# copied to the Secret named example-com-tls. These labels and annotations will
# be re-reconciled if the Certificate's secretTemplate changes. secretTemplate
# is also enforced, so relevant label and annotation changes on the Secret by a
# third party will be overwriten by cert-manager to match the secretTemplate.
secretTemplate:
annotations:
my-secret-annotation-1: "foo"
my-secret-annotation-2: "bar"
labels:
my-secret-label: foo
duration: 2160h # 90d
renewBefore: 360h # 15d
subject:
organizations:
- jetstack
# The use of the common name field has been deprecated since 2000 and is
# discouraged from being used.
commonName: example.com
isCA: false
privateKey:
algorithm: RSA
encoding: PKCS1
size: 2048
usages:
- server auth
- client auth
# At least one of a DNS Name, URI, or IP address is required.
dnsNames:
- example.com
- www.example.com
uris:
- spiffe://cluster.local/ns/sandbox/sa/example
ipAddresses:
- 192.168.0.5
# Issuer references are always required.
issuerRef:
name: ca-issuer
# We can reference ClusterIssuers by changing the kind here.
# The default value is Issuer (i.e. a locally namespaced Issuer)
kind: Issuer
# This is optional since cert-manager will default to this value however
# if you are using an external issuer, change this to that issuer group.
group: cert-manager.io
Still not sure how to sync it with the kubebuilder to work locally
as when I run the operator in debug mode I got the following error:
setup problem running manager {"error": "open /var/folders/vh/_418c55133sgjrwr7n0d7bl40000gn/T/k8s-webhook-server/serving-certs/tls.crt: no such file or directory"}
What I need is the simplest way to run webhooks locally

Answer 1

Let me walk you through the process from the start.
create webhook like it's said in the cronJob tutorial - kubebuilder create webhook --group batch --version v1 --kind CronJob --defaulting --programmatic-validation . This will create webhooks for implementing defaulting logics and validating logics.
Implement the logics as instructed - Implementing defaulting/validating webhooks
Install cert-manager. I find the easiest way to install is via this commmand - kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.10.1/cert-manager.yaml
Edit the config/default/kustomization.yaml file by uncommenting everything that have [WEBHOOK] or [CERTMANAGER] in their comments. Do the same for config/crd/kustomization.yaml file also.
Build Your Image locally using - make docker-build IMG=<some-registry>/<project-name>:tag. Now you dont need to docker-push your image to remote repository. If you are using kind cluster, You can directly load your local image to your specified kind cluster:
kind load docker-image <your-image-name>:tag --name <your-kind-cluster-name>
Now you can deploy it to your cluster by - make deploy IMG=<some-registry>/<project-name>:tag.
You can also run cluster locally using make run command. But, that's a little tricky if you have enabled webooks. I would suggest you running your cluster using KIND cluster in this way. Here, you don't need to worry about injecting certificates. cert-manager will do that for you. You can check out the /config/certmanager folder to figure out how this is functioning.