sync-upstream.yml

name: Sync with Upstream

on:
  schedule:
    # Run every Monday at 9 AM UTC
    - cron: '0 9 * * 1'
  workflow_dispatch:
    inputs:
      sync_branch:
        description: 'Branch to sync from upstream'
        required: false
        default: 'main'
        type: string

jobs:
  sync:
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write
      issues: write
    
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}
      
      - name: Configure git
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
      
      - name: Add upstream remote
        run: |
          git remote add upstream https://github.com/jhipster/prettier-java.git || true
          git fetch upstream
      
      - name: Create sync branch
        id: sync
        run: |
          UPSTREAM_BRANCH="${{ github.event.inputs.sync_branch || 'main' }}"
          SYNC_BRANCH="sync-upstream-$(date +%Y%m%d-%H%M%S)"
          
          echo "upstream_branch=$UPSTREAM_BRANCH" >> $GITHUB_OUTPUT
          echo "sync_branch=$SYNC_BRANCH" >> $GITHUB_OUTPUT
          
          # Create a new branch from our main
          git checkout -b "$SYNC_BRANCH" origin/main
          
          # Try to merge upstream changes
          if git merge upstream/"$UPSTREAM_BRANCH" --no-edit; then
            echo "merge_success=true" >> $GITHUB_OUTPUT
            echo "✅ Successfully merged upstream changes" >> $GITHUB_STEP_SUMMARY
          else
            echo "merge_success=false" >> $GITHUB_OUTPUT
            echo "❌ Merge conflicts detected" >> $GITHUB_STEP_SUMMARY
            
            # Show conflict details
            echo "### Conflicts in the following files:" >> $GITHUB_STEP_SUMMARY
            git diff --name-only --diff-filter=U >> $GITHUB_STEP_SUMMARY
            
            # Abort the merge
            git merge --abort
            
            # Cherry-pick what we can
            echo "### Attempting to cherry-pick non-conflicting commits..." >> $GITHUB_STEP_SUMMARY
            MERGE_BASE=$(git merge-base HEAD upstream/"$UPSTREAM_BRANCH")
            COMMITS=$(git rev-list --reverse $MERGE_BASE..upstream/"$UPSTREAM_BRANCH")
            
            for commit in $COMMITS; do
              if git cherry-pick $commit 2>/dev/null; then
                echo "✅ Cherry-picked: $(git log -1 --oneline $commit)" >> $GITHUB_STEP_SUMMARY
              else
                git cherry-pick --abort 2>/dev/null || true
                echo "❌ Could not cherry-pick: $(git log -1 --oneline $commit)" >> $GITHUB_STEP_SUMMARY
              fi
            done
          fi
          
          # Check if there are any changes to push
          if git diff --quiet origin/main; then
            echo "has_changes=false" >> $GITHUB_OUTPUT
            echo "ℹ️ No changes to sync from upstream" >> $GITHUB_STEP_SUMMARY
          else
            echo "has_changes=true" >> $GITHUB_OUTPUT
            git push origin "$SYNC_BRANCH"
          fi
      
      - name: Create Pull Request
        if: steps.sync.outputs.has_changes == 'true'
        uses: peter-evans/create-pull-request@v5
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          branch: ${{ steps.sync.outputs.sync_branch }}
          base: main
          title: '🔄 Sync with upstream prettier-java'
          body: |
            ## Upstream Sync
            
            This PR syncs changes from the upstream [prettier-java](https://github.com/jhipster/prettier-java) repository.
            
            - **Source branch**: `upstream/${{ steps.sync.outputs.upstream_branch }}`
            - **Merge status**: ${{ steps.sync.outputs.merge_success == 'true' && '✅ Clean merge' || '⚠️ Manual conflict resolution required' }}
            
            ### What to do next:
            
            ${{ steps.sync.outputs.merge_success == 'true' && '1. Review the changes\n2. Run tests locally\n3. Merge when ready' || '1. Checkout this branch locally\n2. Resolve merge conflicts\n3. Push the resolved changes\n4. Run tests\n5. Merge when ready' }}
            
            ### Automated sync details:
            
            <details>
            <summary>View sync summary</summary>
            
            ```
            ${{ steps.sync.outputs.summary || 'See workflow run for details' }}
            ```
            
            </details>
          labels: |
            upstream-sync
            ${{ steps.sync.outputs.merge_success == 'false' && 'has-conflicts' || '' }}
          assignees: ${{ github.repository_owner }}
      
      - name: Create Issue for Conflicts
        if: steps.sync.outputs.has_changes == 'true' && steps.sync.outputs.merge_success == 'false'
        uses: peter-evans/create-issue-from-file@v4
        with:
          title: '⚠️ Upstream sync conflicts detected'
          content-filepath: /dev/stdin
          labels: upstream-sync, needs-attention
          assignees: ${{ github.repository_owner }}
        with: |
          ## Upstream Sync Conflicts
          
          The automated sync with upstream prettier-java has detected merge conflicts that require manual resolution.
          
          **Pull Request**: See the latest PR with the `upstream-sync` and `has-conflicts` labels
          
          ### Affected files:
          
          Check the PR description for the list of conflicting files.
          
          ### Resolution steps:
          
          1. Checkout the sync branch locally
          2. Resolve conflicts manually  
          3. Test the changes
          4. Push the resolved changes
          5. Merge the PR when ready
          
          ---
          
          *This issue was automatically created by the upstream sync workflow.*