Add comment on PR with PDF link

Author: petebachant

.github/workflows/run.yml

@@ -8,6 +8,7 @@ on:
 
 permissions:
   contents: write
+  pull-requests: write  # Add this for PR comments
 
 # Make sure we only ever run one per branch so we don't have issues pushing
 # after running the pipeline
@@ -58,6 +59,26 @@ jobs:
       - run: calkit save -am "Run pipeline"
         env:
           CALKIT_DVC_TOKEN: ${{ secrets.CALKIT_DVC_TOKEN }}
+      - name: Upload PDF artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: paper-pdf
+          path: paper/paper.pdf
+          if-no-files-found: warn
+      - name: Comment on PR with PDF link
+        if: github.event_name == 'pull_request'
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const fs = require('fs');
+            if (fs.existsSync('paper/paper.pdf')) {
+              github.rest.issues.createComment({
+                issue_number: context.issue.number,
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                body: '📄 **Pipeline completed!** The generated PDF is available as an artifact in this workflow run: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}'
+              });
+            }
       - name: Save DVC cache
         id: cache-dvc-save
         uses: actions/cache/save@v4