Node.js Web Development - Fourth Edition

Tracing events on the Page and the Puppeteer instance

Another useful tactic is to generate a trace of what happened so you can puzzle away. Inserting console.log statements is tedious and makes your code look a little ugly. Puppeteer offers a couple of methods to trace the actions and to dynamically turn off tracing.

In uitest.js, add this code:

function frameEvent(evtname, frame) {    console.log(`${evtname} ${frame.url()} ${frame.title()}`);}function ignoreURL(url) {    if (url.match(/\/assets\//) === null      && url.match(/\/socket.io\//) === null     && url.match(/fonts.gstatic.com/) === null     && url.match(/fonts.googleapis.com/) === null) {        return false;    } else {        return true;    }}...before(async function() { browser = await puppeteer.launch({ slomo: ...