feat(jenkins): remove deprecated 'jenkins' package

[CryptoRodeo]

Hey, I just made a Pull Request!

Remove the deprecated jenkins NPM package and replace it with a built-in lightweight client.

The goal of this client is for it to be "drop-in" and minimize changes where the original client was called.

Should fix #4984

Basic Jenkins plugin operations

These still work as expected (at least for me 😄)

jenkins-backstage-demo-basic.mp4

Scaffolder functionality

The Scaffolder still works the same:

jenkins-scaffolder-demo-basic.mp4

For reference here is the template I used:

apiVersion: scaffolder.backstage.io/v1beta3
kind: Template
metadata:
  name: debug-jenkins
  title: Debug Jenkins
spec:
  owner: guests
  type: service
  system: examples
  lifecycle: experimental
  steps:
    - id: create
      name: Create Jenkins job
      action: jenkins:job:create
      input:
        jobName: demo
        jobXml: |
          <flow-definition plugin="workflow-job">
            <definition class="org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition" plugin="workflow-cps">
              <script>pipeline { agent any; stages { stage('hi'){steps{ echo 'hello' } } } }</script>
              <sandbox>true</sandbox>
            </definition>
          </flow-definition>

    - id: clone
      name: Clone Jenkins Job
      action: jenkins:job:copy
      input:
        sourceJobName: demo
        targetJobName: demoClone

    - id: build
      name: Trigger build
      action: jenkins:job:build
      input:
        jobName: demo

    - id: disable
      name: Disable job
      action: jenkins:job:disable
      input:
        jobName: demo

    - id: enable
      name: Re-enable job
      action: jenkins:job:enable
      input:
        jobName: demo

    - id: destroy
      name: Destroy job
      action: jenkins:job:destroy
      input:
        jobName: demo

    - id: destroy copy
      name: Destroy job copy
      action: jenkins:job:destroy
      input:
        jobName: demoClone

✔️ Checklist

• A changeset describing the change and affected packages. (more info)
• Added or updated documentation
• Tests for new functionality and regression tests for bug fixes
• Screenshots attached (for UI changes)
• All your commits have a Signed-off-by line in the message. (more info)

[backstage-goalie]

Changed Packages

Package Name	Package Path	Changeset Bump	Current Version
@backstage-community/plugin-jenkins-backend	workspaces/jenkins/plugins/jenkins-backend	minor	v0.20.0
@backstage-community/plugin-jenkins-common	workspaces/jenkins/plugins/jenkins-common	minor	v0.12.0
@backstage-community/plugin-scaffolder-backend-module-jenkins	workspaces/jenkins/plugins/scaffolder-backend-module-jenkins	minor	v0.14.0

[CryptoRodeo]

So far no issues connecting to my Jenkins instance:

basic-jenkins-test.mp4

Jenkins scaffolder also works:

jenkins-scaffolder-test.mp4

[github-actions]

This PR has been automatically marked as stale because it has not had recent activity from the author. It will be closed if no further activity occurs. If the PR was closed and you want it re-opened, let us know and we'll re-open the PR so that you can continue the contribution!

[CryptoRodeo]

Bump for stale bot

[awanlin]

Sorry this isn't getting the review it needs @CryptoRodeo. I'm heads down prepping for BackstageCon on Monday. But this is on my radar to review in full!

[CryptoRodeo]

No worries. Thanks for the heads up @awanlin , have fun at BackstageCon!

[awanlin]

Thanks a ton for taking on this work @CryptoRodeo, gave those a decent read over and looks good to me. One thing I'd like to know: how much of this was from scratch vs pulled from the archived package? I'm just wondering if we need to add some sort of comment about that int he docs somewhere or not. 🤔

[CryptoRodeo]

@awanlin I used the code from the archived package as a reference to ensure backwards compatibility, but nothing should be copy-pasted from the actual code base. So it's from scratch but built using a reference (does that make sense?)

I could add somewhere that originally this plugin used the deprecated package but now it's using a built in client that's inspired/references that package?