Launch puppeteer browser on app start

print/boot.js

@@ -1,11 +1,13 @@
 const express = require('express');
 const path = require('path');
 const fs = require('fs');
+const puppeteer = require('puppeteer');
 
 const templatesPath = path.resolve(__dirname, './templates');
 const componentsPath = path.resolve(__dirname, './core/components');
+const config = require('./core/config');
 
-module.exports = app => {
+module.exports = async app => {
     global.appPath = __dirname;
 
     process.env.OPENSSL_CONF = '/etc/ssl/';
@@ -51,4 +53,16 @@ module.exports = app => {
             app.use(`/api/${templateName}/assets`, express.static(assetsDir));
         });
     });
+
+    // Instantiate Puppeteer browser
+    async function launchBrowser() {
+        config.browser = await puppeteer.launch({
+            headless: true,
+            args: ['--no-sandbox', '--disable-setuid-sandbox']
+        });
+
+        config.browser.on('disconnected', launchBrowser);
+    }
+
+    launchBrowser();
 };

print/core/report.js

@@ -1,5 +1,4 @@
 const fs = require('fs');
-const puppeteer = require('puppeteer');
 const path = require('path');
 const config = require('./config');
 const Component = require('./component');
@@ -28,11 +27,7 @@ class Report extends Component {
         if (fs.existsSync(fullPath))
             options = require(optionsPath);
 
-        const browser = await puppeteer.launch({
-            headless: true,
-            args: ['--no-sandbox', '--disable-setuid-sandbox']
-        });
-        const page = await browser.newPage();
+        const page = await config.browser.newPage();
         await page.emulateMedia('screen');
         await page.setContent(template);
 
@@ -51,7 +46,6 @@ class Report extends Component {
         options.footerTemplate = footer;
 
         const buffer = await page.pdf(options);
-        await browser.close();
 
         return buffer;
     }