feat: add preferred channel slug

[FourSigma]

• Allows KOTS to bootstrap with a preferred channel slug to support multi-channel licenses.

• When you kubectl kots install my-app beta, KOTS will now store the preferred channel slug beta in a ConfigMap.

• This will allow KOTS to hit a new upstream endpoint in replicated-app - /license/:appSlug/:channelSlug to download the definitive channel specific license

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Steps to reproduce

Does this PR introduce a user-facing change?

Does this PR require documentation?

[divolgin]

This should be in the same arg as app slug, as shown in the docs: https://docs.replicated.com/reference/kots-cli-install#examples

kubectl kots install kots-sentry/stable

[sgalsaleh]

+1

[pandemicsyn]

@divolgin @sgalsaleh Just confirming. Right now this would result in having a whole new arg that would be redundant (e.g. kubectl kots install kots-sentry/stable stable) . But we can just pluck the channel out of the upstreamURI - created right above on line 164 (maybe with ParseReplicatedURL) ?

[divolgin]

yes, and it's optional. should default to "stable"

[pandemicsyn]

ah cool 👍 will send along one more update to use the default.

[sgalsaleh]

I would suggest using the existing GetInstallationParams function:

kots/pkg/kotsutil/kots.go

Line 1144 in 2dae2bf

func GetInstallationParams(configMapName string) (InstallationParams, error) {

[sgalsaleh]

Example usage:

kots/pkg/automation/automation.go

Lines 238 to 241 in 2dae2bf

	instParams, err := kotsutil.GetInstallationParams(kotsadmtypes.KotsadmConfigMap)
	if err != nil {
	return errors.Wrap(err, "failed to get existing kotsadm config map")
	}

[sgalsaleh]

Also, if you don't mind, can you just have that GetInstallationParams always use kotsadmtypes.KotsadmConfigMap and not have to accept it as a parameter?

[pandemicsyn]

@sgalsaleh safe for me to update RemoveAppVersionLabelFromInstallationParams while im at it?

kots/pkg/kotsutil/kots.go

Line 1313 in 2dae2bf

func RemoveAppVersionLabelFromInstallationParams(configMapName string) error {

Has the same func sig and inline use of configMapName as GetInstallationParams

[pandemicsyn]

fyi - went ahead updated RemoveAppVersionLabelFromInstallationParams too (but easy to undo if I shouldn't have).

[sgalsaleh]

just to confirm, is the idea that this decision will be recorded by replicated.app and this channel will be used automatically by replicated.app for subsequent requests?

[pandemicsyn]

@sgalsaleh i think the answer is yes. At least for requests to this endpoint, I'm not sure how this plays out in other areas. But hoping @marccampbell or maybe @divolgin can confirm.

Over on the pending replicated.app pr from Siva he mentioned:

We now check for the existence of a row in the license_instance table. If it exists, we use the channelId from that table to generate the license in L245. This prevents the downstream from switching channels once initialized and recorded on the license_instance table.

And does look like it actually does that. If there was a licenseInstance entry it will use that channel id instead:

license = await stores.licenseStore.getLicenseFromIdAndChannelSlugId(licenseInstance.licenseId, licenseInstance.downstreamChannelId);

[divolgin]

Hard to comment on code that has been removed 😄 :

• Handler still has channel slug in it while client does not?: @Get("/:appSlug/:channelSlug")
• Instance data is recoded asynchronously and may be delayed.
• When channel on a license changes, instance can make any number of requests before reporting new channel
  • There is also a distinction between what channel license is assigned to and what channel is currently deployed
• This should be tested e2e with a channel other than "stable" with a brand new instance

[CLAassistant]

All committers have signed the CLA.

[pandemicsyn]

closing in favor of (wip) #4767