Refactor image rendering to use a browser pool and update dependencies

api.js

@@ -1,8 +1,8 @@
 const express = require('express');
-const nodeHtmlToImage = require('node-html-to-image');
 const fs = require('fs');
 const path = require('path');
 const crypto = require('crypto');
+const { initPool, renderHtml, POOL_SIZE } = require('./browserPool');
 
 const app = express();
 const PORT = 3000;
@@ -262,20 +262,7 @@ async function generateQuoteBuffer(config) {
 </body>
 </html>`;
 
-    const image = await nodeHtmlToImage({
-        html: html,
-        puppeteerArgs: {
-            args: ['--no-sandbox'],
-            defaultViewport: {
-                width: 3240,
-                height: 3240
-            }
-        },
-        beforeScreenshot: async (page) => {
-            await new Promise(resolve => setTimeout(resolve, 1000));
-        }
-    });
-
+    const image = await renderHtml(html, 1000);
     return image;
 }
 
@@ -400,9 +387,16 @@ setInterval(() => {
     cleanupOldCache();
 }, 60 * 60 * 1000);
 
-app.listen(PORT, () => {
-    console.log(`Quote generator API running on http://localhost:${PORT}`);
-    console.log(`GET:  http://localhost:${PORT}/generate?text=Hello&displayName=Test&username=@test&timestamp=1735574400`);
-    console.log(`POST: http://localhost:${PORT}/generate`);
-    console.log(`Cache cleared on startup, cleanup runs every hour`);
+// Initialize browser pool then start server
+initPool().then(() => {
+    app.listen(PORT, () => {
+        console.log(`Quote generator API running on http://localhost:${PORT}`);
+        console.log(`Browser pool size: ${POOL_SIZE} (set BROWSER_POOL_SIZE env var to change)`);
+        console.log(`GET:  http://localhost:${PORT}/generate?text=Hello&displayName=Test&username=@test&timestamp=1735574400`);
+        console.log(`POST: http://localhost:${PORT}/generate`);
+        console.log(`Cache cleared on startup, cleanup runs every hour`);
+    });
+}).catch(err => {
+    console.error('Failed to initialize browser pool:', err);
+    process.exit(1);
 });