perf: ⚡️ add batch printing to pdf

src/lib/printer/index.js

@@ -1,69 +1,80 @@
-const puppeteer = require("playwright-core");
+const playwright = require("playwright-core");
 const fs = require("fs");
 const { sluggify } = require("../html-prettifier/slugger");
 const { languages } = require("../../config/locales.json");
 
 const allLanguages = Object.keys(languages);
+const CONCURRENCY_LIMIT = 2;
 
-(async function printPDF() {
-  let browser;
+async function generatePDF(browser, url, shortLang) {
+  const page = await browser.newPage();
+  try {
+    console.log(`opening page: ${url}`);
+    await page.goto(url, {
+      waitUntil: "networkidle0",
+      timeout: 0,
+    });
+
+    const pdf = await page.pdf({
+      printBackground: true,
+      preferCSSPageSize: true,
+      quality: 100,
+      format: "A4",
+      margin: { top: "20px", right: "20px", bottom: "20px", left: "20px" },
+      timeout: 0,
+    });
+
+    const pdfFile = `/vreji/uencu/${shortLang}/${url.split("/").slice("-1")[0]}.pdf`;
+    fs.mkdirSync(`/vreji/uencu/${shortLang}`, { recursive: true });
+    fs.writeFileSync(pdfFile, pdf);
+    console.log(`pdf file saved: ${pdfFile}`);
+  } catch (error) {
+    console.error(`Error generating PDF for ${url}:`, error);
+  } finally {
+    await page.close();
+  }
+}
+
+async function processBatch(browser, urls, shortLang) {
+  const results = [];
+  for (let i = 0; i < urls.length; i += CONCURRENCY_LIMIT) {
+    const batch = urls.slice(i, i + CONCURRENCY_LIMIT);
+    const batchPromises = batch.map(url => generatePDF(browser, url, shortLang));
+    results.push(...await Promise.all(batchPromises));
+  }
+  return results;
+}
+
+async function printPDF() {
   for (const lang of allLanguages) {
     const shortLang = languages[lang].short;
     try {
       const urls = fs
         .readdirSync(`/app/src/md_pages/${shortLang}/books/`)
         .filter((i) => i.endsWith(".md"))
-        .map((i) => sluggify(i.replace(/.md$/, "")));
+        .map((i) => sluggify(i.replace(/.md$/, "")))
+        .map((url) => `http://127.0.0.1:3000/${shortLang}/books/${url}`);
 
       console.log("generating PDF files for", urls);
-      browser = await puppeteer.chromium.launch({
+      const browser = await playwright.chromium.launch({
         headless: true,
         args: [
           "--disable-dev-shm-usage",
           "--no-sandbox",
           "--disable-setuid-sandbox",
         ],
       });
-      const page = await browser.newPage();
-      for (let url of urls) {
-        url = `http://127.0.0.1:3000/${shortLang}/books/` + url;
-        console.log(`opening page: ${url}`);
-        await page.goto(url, {
-          waitUntil: "networkidle0",
-          timeout: 0,
-        });
-        // await new Promise(resolve => setTimeout(resolve, 1500));
-        // await page.screenshot();
-        // await page.evaluateHandle('document.fonts.ready');
 
-        // let div_selector_to_remove = ".print:hidden";
-        // await page.evaluate((sel) => {
-        //   const elements = document.querySelectorAll(sel);
-        //   for (let i = 0; i < elements.length; i++) {
-        //     elements[i].parentNode.removeChild(elements[i]);
-        //   }
-        // }, div_selector_to_remove);
-        const pdf = await page.pdf({
-          printBackground: true,
-          preferCSSPageSize: true,
-          quality: 100,
-          format: "A4",
-          margin: { top: "20px", right: "20px", bottom: "20px", left: "20px" },
-          timeout: 0,
-        });
-        const pdfFile =
-          `/vreji/uencu/${shortLang}/` +
-          url.split("/").slice("-1")[0] +
-          "-pre.pdf";
-        fs.mkdirSync(`/vreji/uencu/${shortLang}`, { recursive: true });
-        fs.writeFileSync(pdfFile, pdf);
-        console.log(`pdf file saved: ${pdfFile}`);
+      try {
+        // Process URLs in batches with concurrency limit
+        await processBatch(browser, urls, shortLang);
+      } finally {
+        await browser.close();
       }
     } catch (err) {
-      continue;
+      console.error(`Error processing language ${lang}:`, err);
     }
-    try {
-      await browser.close();
-    } catch (error) {}
   }
-})();
+}
+
+printPDF().catch(console.error);