add Upstream Sync

.github/workflows/sync.yml

@@ -0,0 +1,54 @@
+name: 'Upstream Sync'
+
+on:
+  schedule:
+    - cron:  '0 7 * * *'
+    # scheduled at 07:00 every day
+
+  workflow_dispatch:  # click the button on Github repo!
+
+jobs:
+  sync_latest_from_upstream:
+    runs-on: ubuntu-latest
+    name: Sync latest commits from upstream repo
+
+    steps:
+    # REQUIRED step
+    # Step 1: run a standard checkout action, provided by github
+    - name: Checkout target repo
+      uses: actions/checkout@v3
+      with:
+        # optional: set the branch to checkout,
+        # sync action checks out your 'target_sync_branch' anyway
+        ref:  dev
+        # REQUIRED if your upstream repo is private (see wiki)
+        persist-credentials: false
+
+    # REQUIRED step
+    # Step 2: run the sync action
+    - name: Sync upstream changes
+      id: sync
+      uses: aormsby/[email protected]
+      with:
+        target_sync_branch: dev
+        # REQUIRED 'target_repo_token' exactly like this!
+        target_repo_token: ${{ secrets.GITHUB_TOKEN }}
+        upstream_sync_branch: dev
+        upstream_sync_repo: jgraph/drawio
+        upstream_repo_access_token: ${{ secrets.UPSTREAM_REPO_SECRET }}
+
+        # Set test_mode true to run tests instead of the true action!!
+        test_mode: false
+
+    # Step 3: Display a sample message based on the sync output var 'has_new_commits'
+    - name: New commits found
+      if: steps.sync.outputs.has_new_commits == 'true'
+      run: echo "New commits were found to sync."
+
+    - name: No new commits
+      if: steps.sync.outputs.has_new_commits == 'false'
+      run: echo "There were no new commits."
+
+    - name: Show value of 'has_new_commits'
+      run: echo ${{ steps.sync.outputs.has_new_commits }}
+