[JENKINS-62345] Introduce FingerprintStorage API in core

[stellargo]

See JENKINS-62345.
See JEP-226

Proposed changelog entries

• Developer: Introduce new Fingerprint API methods: Fingerprint#getPersistedFacets(), Fingerprint#delete(String). Deprecated methods: Fingerprint#save(File). This API expects usage of standard CRUD operations like Fingerprint#save(), Fingerprint#load(String) and Fingerprint#delete(String)
• Developer: Add experimental External Fingerprint Storage API
  • JEP-226 - https://github.com/jenkinsci/jep/tree/master/jep/226
  • Reference Implementation - https://github.com/jenkinsci/redis-fingerprint-storage-plugin

Proposed upgrade guidelines

N/A

Submitter checklist

• (If applicable) Jira issue is well described
• Changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developer, depending on the change). Examples
  • Fill-in the Proposed changelog entries section only if there are breaking changes or other changes which may require extra steps from users during the upgrade
• Appropriate autotests or explanation to why this change has no tests
• For dependency updates: links to external changelogs and, if possible, full diffs

Desired reviewers

@mention

Maintainer checklist

Before the changes are marked as ready-for-merge:

• There are at least 2 approvals for the pull request and no outstanding requests for change
• Conversations in the pull request are over OR it is explicit that a reviewer does not block the change
• Changelog entries in the PR title and/or Proposed changelog entries are correct
• Proper changelog labels are set so that the changelog can be generated automatically
• If the change needs additional upgrade steps from users, upgrade-guide-needed label is set and there is a Proposed upgrade guidelines section in the PR title. (example)
• If it would make sense to backport the change to LTS, a Jira issue must exist, be a Bug or Improvement, and be labeled as lts-candidate to be considered (see query).

[stellargo]

This draft PR is what I will be working on for changes on the core side. I have made some basic adjustments as a start for moving the saving functionality to FileFingerprintStorage.
CC @oleg-nenashev @afalko @mikecirioli

[stellargo]

Apologies for the force push, I really messed up the git history, so had to do it :(

[StefanSpieker]

Shouldn't new files be better placed in the Jenkins namespace instead of hudson? I did not check if this has implications.

[stellargo]

@oleg-nenashev Thanks! Incorporated the changes :)

[oleg-nenashev]

From what I see, it is ready to go. Thanks a lot for the hard work @stellargo !

Before we merge it, we need to prepare changelog entries for the pull request. See the Pull request template for examples. I would suggest two entries:

• Developer API change for the new Fingerprint API and deprecating old File ones (CRUD, retrieving persisted facets)
• New Experimental External Fingerprint Storage API (with a link to JEP and a reference implementation)

[stellargo]

Credentials plugin ran successfully without any failing tests on this PR's incremental build https://ci.jenkins.io/blue/organizations/jenkins/Plugins%2Fcredentials-plugin/detail/PR-153/1/pipeline

[stellargo]

@oleg-nenashev Thank you for reviewing, I have added the suggested changelog entries. Kindly let me know if any more changes are required :)

[oleg-nenashev]

We may merge it in 24 hours if there is no negative feedback. Please see the merge process documentation for more information about the merge process

[timja]

looks good,

I haven't ran it interactively.

no blockers, if you have time there's some minor improvements that could be made to docs and code style.

[daniel-beck]

This entire class needs an @since TODO, same with FileFingerprintStorage.

[daniel-beck]

@since?