[TASK] Migrate backport to shared reusable workflow

[CybotTM]

Problem

The backport workflow is currently inlined in each repo with identical configuration. When m-kuhn/backport@30b6e83 broke (missing dist/index.js), each repo had to be fixed individually. 7 repos still use the broken action:

• TYPO3CMS-Reference-TCA
• TYPO3CMS-Reference-Typoscript
• TYPO3CMS-Reference-ViewHelper
• TYPO3CMS-Tutorial-GettingStarted
• TYPO3CMS-Tutorial-SitePackage
• TYPO3CMS-Guide-FrontendLocalization
• blog_example

CoreApi was already fixed (migrated to korthout/backport-action), but the workflow is still inlined.

Solution

Replace the inline workflow with a call to the shared reusable workflow from TYPO3-Documentation/.github, the org's community health repository. This wraps korthout/backport-action and is automatically accessible to all repos in the org without allow-list changes.

Before/After

Before (22 lines, inline, maintained per-repo):

jobs:
  backport:
    if: github.event.pull_request.merged == true
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write
    steps:
      - uses: actions/checkout@...
      - uses: korthout/backport-action@...
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}

After (5 lines, shared, maintained centrally):

jobs:
  backport:
    uses: TYPO3-Documentation/.github/.github/workflows/reusable-backport.yml@main
    with:
      label_pattern: "backport *"

Benefits

• Single point of maintenance — update the action version once, all repos benefit
• Consistent configuration — label patterns, permissions, behavior identical everywhere
• Faster incident response — broken action? Fix one repo, not 8
• No allow-list changes needed — the .github repo is the org community health repo, automatically trusted by all org repos

Status

Same change needed in 7 other repos. Companion PRs:

• [TASK] Migrate backport and documentation workflows to shared reusable workflows TYPO3CMS-Tutorial-Editors#258
• [TASK] Migrate CI to shared reusable workflows render-guides#1196

Dependencies and merge order

• Depends on .github#4 (backport label_pattern fix on main)
• Uses reusable-backport.yml which already exists on .github main

[garvinhicking]

(Please note this is a POC we should not merge as-is, because we'd first have to import the referenced repo into our own maintenance scope. Thanks a lot, this is very helpful for discussion!)

[linawolf]

@CybotTM thanks for your work. Could we put the into https://github.com/TYPO3-Documentation/t3docs-ci-deploy? it is already the repository for "Build and Deployment Pipelines".

[CybotTM]

@linawolf, yes of course!

[CybotTM]

@linawolf like this TYPO3-Documentation/t3docs-ci-deploy#56 ?

[CybotTM]

Updated for merged TYPO3-Documentation/t3docs-ci-deploy#56

[linawolf]

I moved your actions to Repo https://github.com/TYPO3-Documentation/.github as suggested by @jaapio and tried out using it like https://github.com/TYPO3-Documentation/TYPO3CMS-Tutorial-GettingStarted/blob/main/.github/workflows/backport.yml but did not get it to working yet. I would suggest we work on that repo as it is smaller and has less changes and trying out workflows there does not influence our daily work so much. After we have successfully tested the workflow we can try it out here

[CybotTM]

@linawolf ,

did you notice this comment:

Org admin action required: The org's GitHub Actions allow-list must permit reusable workflow calls to TYPO3-Documentation/t3docs-ci-deploy. This can be configured at Organization Settings > Actions > General. Without this, workflows referencing t3docs-ci-deploy reusable workflows will fail with startup_failure.

[linawolf]

Let us continue in https://github.com/TYPO3-Documentation/TYPO3CMS-Tutorial-GettingStarted please. The repository we are currently in is to much frequented for experiments. Also, the reusable actions where moved to TYPO3-Documentation/.github