sync-mailing-list-mirror.yml

name: sync-mailing-list-mirror

on:
  workflow_dispatch:
  schedule:
    - cron:  "*/5 * * * *"

env:
  MIRROR_REF: ${{ fromJSON(vars.CONFIG).mailrepo.mirrorRef }}
  SOURCE_REPOSITORY: ${{ fromJSON(vars.CONFIG).mailrepo.url }}${{ fromJSON(vars.CONFIG).mailrepo.public_inbox_epoch }}
  TARGET_GITHUB_REPOSITORY: ${{ fromJSON(vars.CONFIG).mailrepo.owner }}/${{ fromJSON(vars.CONFIG).mailrepo.name }}

concurrency:
  group: sync-mailing-list-mirror
  cancel-in-progress: true

jobs:
  sync-mailing-list-mirror:
    runs-on: ubuntu-latest
    permissions:
      contents: write
    steps:
    - name: check if update is needed
      id: needs-update
      run: |
        set -x
        echo "org=${TARGET_GITHUB_REPOSITORY%%/*}" >>$GITHUB_OUTPUT &&
        echo "repo=${TARGET_GITHUB_REPOSITORY#*/}" >>$GITHUB_OUTPUT &&
        source="$(git ls-remote "$SOURCE_REPOSITORY" master)" &&
        target="$(git ls-remote https://github.com/"$TARGET_GITHUB_REPOSITORY" "$MIRROR_REF")" &&
        echo "result=$(test "${source%%	*}" = "${target%%	*}" && echo false || echo true)" >>$GITHUB_OUTPUT
    - name: Partial clone
      if: steps.needs-update.outputs.result == 'true'
      run: |
        git clone --bare --depth=1 -b "${MIRROR_REF#refs/heads/}" --filter=blob:none https://github.com/$TARGET_GITHUB_REPOSITORY .
    - name: Update from lore.kernel.org
      if: steps.needs-update.outputs.result == 'true'
      run: |
        git fetch "$SOURCE_REPOSITORY" refs/heads/master:"$MIRROR_REF"
    - name: obtain installation token
      if: steps.needs-update.outputs.result == 'true'
      uses: actions/create-github-app-token@v2
      id: token
      with:
        app-id: ${{ secrets.GITGITGADGET_GITHUB_APP_ID }}
        private-key: ${{ secrets.GITGITGADGET_GITHUB_APP_PRIVATE_KEY }}
        owner: ${{ steps.needs-update.outputs.org }}
        repositories: ${{ steps.needs-update.outputs.repo }}
    - name: Push to mirror
      if: steps.needs-update.outputs.result == 'true'
      env:
        GITHUB_TOKEN: ${{ steps.token.outputs.token }}
      run: |
        git push https://$GITHUB_ACTOR:$GITHUB_TOKEN@github.com/$TARGET_GITHUB_REPOSITORY "$MIRROR_REF"