ci: Auto-push high-resolution slide renders.

Author: lemon-mint

.github/workflows/render-slides.yml

@@ -20,8 +20,12 @@ on:
       - "package-lock.json"
       - ".github/workflows/render-slides.yml"
 
+concurrency:
+  group: render-release-note-slides
+  cancel-in-progress: true
+
 permissions:
-  contents: read
+  contents: write
 
 jobs:
   render:
@@ -46,8 +50,18 @@ jobs:
       - name: Render and validate slides
         run: npm run render
 
-      - name: Verify committed PNG files
-        run: git diff --exit-code -- go1.27/overview.png go1.27/overview-ko.png
+      - name: Commit rendered PNG files
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+        run: |
+          git add go1.27/overview.png go1.27/overview-ko.png
+          if git diff --cached --quiet; then
+            echo "Rendered PNG files are already current."
+            exit 0
+          fi
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git commit -m "chore: Render Go 1.27 slides [skip ci]"
+          git push
 
       - name: Upload rendered slides
         uses: actions/upload-artifact@v4

scripts/render-slides.mjs

@@ -6,6 +6,10 @@ import { chromium } from "playwright";
 
 const projectRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
 const requestedTargets = process.argv.slice(2);
+const renderScale = Number(process.env.PNG_SCALE ?? 3);
+if (!Number.isInteger(renderScale) || renderScale < 1 || renderScale > 4) {
+  throw new Error("PNG_SCALE must be an integer from 1 to 4");
+}
 
 const mimeTypes = new Map([
   [".css", "text/css; charset=utf-8"],
@@ -126,7 +130,7 @@ try {
   for (const file of slideFiles) {
     const page = await browser.newPage({
       viewport: { width: 1200, height: 900 },
-      deviceScaleFactor: 1,
+      deviceScaleFactor: renderScale,
     });
     const browserErrors = [];
     page.on("console", (message) => {
@@ -195,7 +199,7 @@ try {
     });
     audits.push({ ...audit, file });
     console.log(
-      `Rendered ${relativeFile} -> ${relative(projectRoot, output)} (${audit.page.width}x${audit.page.height})`,
+      `Rendered ${relativeFile} -> ${relative(projectRoot, output)} (${audit.page.width * renderScale}x${audit.page.height * renderScale}, ${renderScale}x)`,
     );
     await page.close();
   }