Manage immutable fields in Kubebuilder validating webhook

Question

According to Kubebuilder documentation, it is possible to implement immutable fields for a given CRD:

We separate out ValidateCreate from ValidateUpdate to allow behavior like making certain fields immutable, so that they can only be set on creation.

Would some of you have some examples or code samples about implementing this?

Did provided answer help you? Do you need more? – kkopczak Jan 11 '22 at 10:09 — kkopczak, Jan 11 '22 at 10:09
Please see my comment below Mr Lance answer. – Fabrice Jammes Jan 11 '22 at 10:25 — Fabrice Jammes, Jan 11 '22 at 10:25

Galletti_Lance · Answer 1 · 2022-01-11T13:10:06.123

2

Using the Kubebuilder example:

func (r *CronJob) ValidateUpdate(old runtime.Object) error {
    oldCronJob, _ := old.(*CronJob)
    if r.Spec.ImmutableField != oldCronJob.Spec.ImmutableField {
        // accumulate errors
    }
    ...
    // return all errors
}

edited Jan 11 '22 at 13:10

answered Jan 10 '22 at 12:45

Galletti_Lance

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This code does not build, I have the error: `old.Spec undefined (type runtime.Object has no field or method Spec)` – Fabrice Jammes Jan 11 '22 at 10:24
1

updated to get the cronjob struct out of the runtime.object – Galletti_Lance Jan 11 '22 at 13:18

Manage immutable fields in Kubebuilder validating webhook

1 Answers1