[FIX JENKINS-40750] Remove cc.xml from core

[daniel-beck]

As this doesn't involve data or other compatibility concerns, I think we can skip the bundled/detached plugins dance in this case.

To be merged only once ccxml plugin exists. WIP plugin: https://github.com/jenkinsci/cctray-xml-plugin

Not sure how to handle toCCStatus, between keep/keep and deprecate/keep, deprecate, and throw exception/remove I opted for the second (after review) in this PR as it appears to be unused everywhere. Feedback welcome.

Proposed changelog entries

* Major RFE: Remove built-in support for CCtray (cc.xml) files. To restore this feature, install the <a href="https://plugins.jenkins.io/cctray-xml">CCTray XML Plugin</a>

[oleg-nenashev]

The binary compatibility issue needs to be fixed. I was also surprised there is no existing Cruise Control plugin for Jenkins...

[daniel-beck]

@oleg-nenashev Addressed your review comment.

[oleg-nenashev]

The current state is fine for me if it is properly changelogged and then mentioned in the upgrade guide for the next LTS

[oleg-nenashev]

@daniel-beck Ridiculously, there was a mention of such integration at one of Russian IT websites (link, in Russian). CC @SvyatoslavRazmyslov. They use CCTray. So maybe this feature as not that dead as we expect. But we can still decouple it to a plugin.

[oleg-nenashev]

UPD: English version of the post is here

[daniel-beck]

@oleg-nenashev Right, I never expected this to be unused -- just no reason to keep it in core, and questionable popularity and no data storage combined mean I don't see the need to add it to the DETACHED_PLUGINS.

[oleg-nenashev]

@daniel-beck since the LTS line is picked, maybe it's a good time to ship it.

/me grumbles about the the API deprecation policy, which would not be easily able to handle such cases anyway

[batmat]

@daniel-beck this is now conflicted, but apparently this was (almost) ready to merge? IIUC, this is still missing a release from https://github.com/jenkinsci/cctray-xml-plugin/ ?

[oleg-nenashev]

@daniel-beck are you still interested in this PR?

[daniel-beck]

@oleg-nenashev I am. Now's probably a good time to implement this given the LTS cycle.

[batmat]

I don't use it personally, and never did. I even had to dig into various websites to understand what this feature was.

But still:

As this doesn't involve data or other compatibility concerns, I think we can skip the bundled/detached plugins dance in this case.

Makes me slightly uncomfortable. That's fine-ish to me, but I have no idea how much this feature is used. But generally we'd add it to split-plugins.txt and the likes. Doing it would be quite easy and guarantee compatibility.

[batmat]

Given it is said to be deprecated and desupported on various websites after a quick search. Given I had no idea what this was before digging into it, I am going to selfishly consider I suppose not a majority of people still know and use CCTray.

So, it looks like extracting this feature as a plugin that users will have to explictly install looks fine.
Let's just be sure we surface it clearly both in the weekly changelog and the LTS upgrade guide, and everything should go mostly fine I think.

[daniel-beck]

I also prepared https://github.com/jenkinsci/cctray-xml-plugin for release. It currently depends on an incrementals deployment of this PR, so everyone can try how it would work.

[batmat]

I filed jenkinsci/cctray-xml-plugin#3 so Incrementals can actually be published.

UPDATE: OK, I read it better and understood seeing the current plugin failure. The plugin is using a Core Incremental version.
Fix upcoming for the linked PR: DONE

[batmat]

Just marked as ready for merge given the approvals. I'm just waiting for last confirmation from @daniel-beck that he's ready to release the plugin.
We'll also want a clear changelog entry for end users in next weekly, and then next LTS.

[daniel-beck]

I'm ready. The plugin has been updated and currently has a dependency on an incremental on core, once this is out I'll release it and reference it in the changelog (and possibly release a temporary 0.1 a bit early with a lower core dependency to make sure it's on the update center).

[batmat]

OK, let's pull the trigger then. Thanks everyone.