I’m working with puppeteer to scrape a webpage that displays various console errors and warnings in the browser. The problem I’m facing is that my puppeteer script isn’t catching all the console messages that appear in the actual browser.
When I open the same page in a regular Chrome browser, I can see lots of different console messages like JavaScript errors, network failures, and security policy violations. But when I run my puppeteer code, it only picks up a small portion of these messages.
Here’s my current implementation:
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const tab = await browser.newPage();
tab.on('console', message => console.log('BROWSER OUTPUT:', message.text()));
await tab.goto('https://example-site-with-errors.com');
await browser.close();
})();
I’ve tried adding delays with setTimeout but that doesn’t help. The console event handler seems to miss most of the browser’s actual console output. Is there a way to capture all types of console messages including CSP violations and resource loading errors?
Yeah, this drove me nuts too lol. Puppeteer’s console listener doesn’t catch everything you see in DevTools. Add page.on(‘pageerror’) for JS crashes and page.on(‘response’) to filter HTTP errors. CSP issues often hide in browser logs instead of console - try adding ‘–enable-logging --v=1’ to your launch args to see Chrome’s internal messages.
This is a common issue when working with Puppeteer to capture console output. Your current implementation captures only JavaScript console messages, while CSP violations and network errors are managed by different browser events. To capture CSP violations, listen for the ‘response’ event and filter for failed requests with status codes between 400 and 500. Use the ‘requestfailed’ event to catch network failures. Additionally, some JavaScript errors are not logged in the console and require a ‘pageerror’ event handler. Ensure all your event listeners are set up before invoking the goto() method, and consider using waitForLoadState to allow the page to fully load before closing the browser.
Hit this same issue a few months back while monitoring a complex web app. Puppeteer’s console event only grabs messages that JS explicitly logs (console.log, console.error, etc.). Most browser errors you see in DevTools come from different sources - you need separate handlers for those. Listen for ‘pageerror’ events to catch uncaught JS exceptions, and ‘requestfailed’ for network failures. CSP violations are especially annoying since they don’t trigger console events consistently across Chrome versions. I got better results by enabling extra logging flags when launching Puppeteer. Add args like ‘–enable-logging’ and ‘–log-level=0’ to your browser launch options. Also worth checking page.metrics() since some errors only surface in the performance timeline.