✨Webhook: Handle crashes

[inteon]

Return "internal server error" if the webhook crashes.

Depends on #2604.

Code is based on https://github.com/kubernetes/kubernetes/blob/c28c2009181fcc44c5f6b47e10e62dacf53e4da0/staging/src/k8s.io/pod-security-admission/cmd/webhook/server/server.go

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[alvaroaleman]

This already exists:

controller-runtime/pkg/webhook/admission/webhook.go

Lines 154 to 164 in 8d817e7

	if wh.RecoverPanic {
	defer func() {
	if r := recover(); r != nil {
	for _, fn := range utilruntime.PanicHandlers {
	fn(r)
	}
	response = Errored(http.StatusInternalServerError, fmt.Errorf("panic: %v [recovered]", r))
	return
	}
	}()
	}

Ref #1900

[inteon]

This already exists:

controller-runtime/pkg/webhook/admission/webhook.go

Lines 154 to 164 in 8d817e7

	if wh.RecoverPanic {
	defer func() {
	if r := recover(); r != nil {
	for _, fn := range utilruntime.PanicHandlers {
	fn(r)
	}
	response = Errored(http.StatusInternalServerError, fmt.Errorf("panic: %v [recovered]", r))
	return
	}
	}()
	}

Ref #1900

Thanks for pointing this out.