SRVLOGIC-203: Schedule midstream main branch sync (#44)

* GHA creation

* Last update

* Uncomment owner check

* Update PR branch name

.github/workflows/main-sync.yml

@@ -0,0 +1,90 @@
+name: Create a PR to sync main branch with main-apache
+
+env:
+  USERNAME: kie-ci
+  USEREMAIL: [email protected]
+  GITHUB_TOKEN: ${{ secrets.APACHE_SYNC_MIDSTREAM_TOKEN }}
+
+on:
+  schedule:
+    - cron:  '0 1 * * 0' 
+  workflow_dispatch:
+
+jobs:
+  sync-main:
+    if: github.repository_owner == 'kiegroup'
+    name: Sync main with main-apache branch
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Generate PR ID
+        id: generate_pr_id
+        run: echo "pr_id=$(date +'%Y-%m-%d')" >> $GITHUB_OUTPUT
+
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          ref: main
+            # By default, checkout@v4 fetches only a single commit unless you specify "fetch-depth: 0". Without this "git merge" throwns an "unrelated histories".
+          fetch-depth: '0'
+
+      - name: Setup git environment
+        run: |
+          git config --global user.name "$USERNAME"
+          git config --global user.email "$USEREMAIL"
+
+      - name: Fetch all
+        run: git fetch --all
+
+      - name: Checkout main branch
+        run: git checkout main
+
+      - name: Create the PR branch
+        run: git checkout -b sync-main-pr-${{ steps.generate_pr_id.outputs.pr_id }}
+
+      - name: Merge main-apache branch excluding white-listed paths
+        id: merge
+        run: |
+          set -x
+          git merge --no-commit origin/main-apache || true
+          git reset origin/main ${{vars.MAIN_SYNC_WORKFLOW_EXCLUDE_PATHS}}
+          if git diff --cached --quiet; then
+              echo "No changes staged for commit."
+          else
+              git commit -m "Merge main-apache and exclude white-listed changes from the merge"
+          fi
+          echo "excluded_files=$(git ls-files -mo | sed -z 's/\n/<br \/>/g')" >> $GITHUB_OUTPUT
+
+      - name: Check for changes
+        id: check_changes
+        run: |
+          if git diff --quiet origin/main; then
+            echo "No changes detected."
+            echo "is_changed=false" >> $GITHUB_OUTPUT
+          else
+            echo "Changes detected."
+            echo "is_changed=true" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Push changes
+        if: steps.check_changes.outputs.is_changed == 'true'
+        run: git push origin sync-main-pr-${{ steps.generate_pr_id.outputs.pr_id }}
+
+      - name: Create the PR
+        if: steps.check_changes.outputs.is_changed == 'true'
+        run: |
+            runUrl="${{github.server_url}}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
+            if [[ -n "${{ steps.merge.outputs.excluded_files }}" ]]; then
+              excludedFiles="${{ steps.merge.outputs.excluded_files }}"
+            else
+              excludedFiles="No files have been excluded<br />"
+            fi
+            prTitle="Automatic PR: Sync main with main-apache (${{steps.generate_pr_id.outputs.pr_id}})"
+            prBody="This pull request has been created by a GitHub workflow to synchronize the main branch with main-apache branch.<br /><br />\
+                <b>:warning:Important:warning:</b><br />Please don't merge using squash, not to loose the git history.<br /><br />\
+                <b>Excluded files:</b><br />${excludedFiles}<br />\
+                [View Action](${runUrl})"
+            if [[ -n "${{ vars.MAIN_SYNC_WORKFLOW_PR_REVIEWERS }}" ]]; then
+                reviewersOption="--reviewer ${{vars.MAIN_SYNC_WORKFLOW_PR_REVIEWERS}}"
+            fi
+            gh pr create --title "${prTitle}" --body "${prBody}" --base main $reviewersOption