✨ (:sparkles, minor) Make it possible to monitor readiness for webhook

[alenkacz]

This is a very minimal implementation of #723

With this in place, one can define a readiness check for webhook like this:

err = mgr.AddReadyzCheck("ready", func(_ *http.Request) error {
		if mgr.GetWebhookServer().Started {
			return nil
		}
		return errors.New("Webhook server not yet started")
	})

there's still a possibility for a very small race because technically all the paths for webhook are bound when srv.Serve is done. But the possibility of hitting it is very small considering that the readiness check has to pick it up, return ready and someone has to make a request over network to that webhook - that will be definitely slower than the processing inside srv.Serve.

If anyone has better idea, I am all ears.

[k8s-ci-robot]

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[alenkacz]

ping @ncdc @vincepri

[ncdc]

@alenkacz thanks for this! @vincepri & I were both on vacation last week, so we'll take a look as soon as we've dug out from our email backlogs 😄

[ncdc]

/assign @ncdc @vincepri

[vincepri]

Let's document this field, I'm wondering though if we should expose it as a method rather than a field on the struct, given that this field isn't safe to use concurrently

[DirectXMan12]

yeah, let's put that behind a method so that it's safe to call concurrently. See also #1155

[databus23]

Should this maybe set back to false if the Serve method returns?

[k8s-ci-robot]

@alenkacz: PR needs rebase.

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[ncdc]

@alenkacz hi, are you still interested in getting this merged?

[fejta-bot]

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/lifecycle stale

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/lifecycle rotten

[alenkacz]

/remove-lifecycle rotten

[alenkacz]

I'll refresh this

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Mark the issue as fresh with /remove-lifecycle stale.
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/lifecycle stale

[sbueringer]

@alenkacz I can take over this issue, if it's okay for you.

[sbueringer]

Has been implemented in #1588
/lgtm (ups :))

[sbueringer]

/lgtm cancel
/close

[k8s-ci-robot]

@sbueringer: Closed this PR.

In response to this:

/lgtm cancel
/close

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