Rename variables for clarity and update browser pool management

browserPool.js

@@ -5,7 +5,7 @@ const VIEWPORT_WIDTH = 3240;
 const VIEWPORT_HEIGHT = 3240;
 
 let browsers = [];
-let availablePages = [];
+let availableBrowsers = [];
 let initPromise = null;
 
 
@@ -22,42 +22,42 @@ async function initPool() {
             });
 
             browsers.push(browser);
-
-            const page = await browser.newPage();
-            await page.setViewport({
-                width: VIEWPORT_WIDTH,
-                height: VIEWPORT_HEIGHT
-            });
-
-            availablePages.push(page);
+            availableBrowsers.push(browser);
         }
 
-        console.log(`Browser pool ready with ${POOL_SIZE} pages`);
+        console.log(`Browser pool ready with ${POOL_SIZE} browsers`);
     })();
 
     return initPromise;
 }
 
-async function acquirePage() {
+async function acquireBrowser() {
     await initPool();
 
-    // wait for available page
-    while (availablePages.length === 0) {
+    // wait for available browser
+    while (availableBrowsers.length === 0) {
         await new Promise(resolve => setTimeout(resolve, 50));
     }
 
-    return availablePages.pop();
+    return availableBrowsers.pop();
 }
 
-function releasePage(page) {
-    availablePages.push(page);
+function releaseBrowser(browser) {
+    availableBrowsers.push(browser);
 }
 
 // renders html and returns screenshot as buffer
 async function renderHtml(html, waitTime = 1000) {
-    const page = await acquirePage();
+    const browser = await acquireBrowser();
+    let page = null;
 
     try {
+        page = await browser.newPage();
+        await page.setViewport({
+            width: VIEWPORT_WIDTH,
+            height: VIEWPORT_HEIGHT
+        });
+
         await page.setContent(html, { waitUntil: 'networkidle0' });
 
         // wait for any animations or laoding
@@ -70,7 +70,8 @@ async function renderHtml(html, waitTime = 1000) {
 
         return screenshot;
     } finally {
-        releasePage(page);
+        if (page) await page.close();
+        releaseBrowser(browser);
     }
 }
 
@@ -83,7 +84,7 @@ async function shutdownPool() {
     }
 
     browsers = [];
-    availablePages = [];
+    availableBrowsers = [];
     initPromise = null;
 
     console.log('Browser pool shut down');