Investigate use of an admission webhook to ease move to beta

[skaegi]

When we go beta we're going to end up with a ton of pre-existing Tekton resources that use apiVersion: tekton.dev/v1alpha1 where-as our stored versions will now be using apiVersion: tekton.dev/v1beta1 or similar.

One practice to help ease migration is to use a MutatingAdmissionWebhook. We should investigate adding one along with a battery of unit tests to validate the handling of apiVersion changes and other simple mutations we want to support.

[vdemeester]

@skaegi note that we already are using a MutatingAdmissionWebhook and we have a slight mechanisms to do conversion… but yeah we need to enhance that and have confidence on it (hence the battery of tests 😝)

[vdemeester]

/assign

[vdemeester]

Small update on this: as #1529 shows (if people are not completely dead 💀 after reading the PR 😹) that it is definitely possible (and not that hard, thanks to knative/pkg code 👼). It comes with a few "gotchas", but it is doable.

@bobcatfish @skaegi Should we close this issue (as we know what is the status) and focus on #1526 ?

[vdemeester]

/close

[tekton-robot]

@vdemeester: Closing this issue.

In response to this:

/close

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