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chrome-headlessHow to take page screenshot with delay using Chrome Remote Interface


We'll wait for 6 seconds before taking screenshot in this example:

const chromeLauncher = require('chrome-launcher');
const CDP = require('chrome-remote-interface');
const fs = require('fs');

chromeLauncher.launch({ port: 9222, chromeFlags: [ '--window-size=400,800', '--headless' ] }).then(function(chrome) {
  CDP(async (client) => {
    const {Page} = client;
    await Page.enable();
    await Page.navigate({url: 'https://github.com'});
    await Page.loadEventFired();
    
    await new Promise(r => setTimeout(r, 6000));
    
    const {data} = await Page.captureScreenshot();
    fs.writeFileSync('screen.png', Buffer.from(data, 'base64'));
    await client.close();
    chrome.kill();
  });
});ctrl + c
require('chrome-launcher')

Chrome-Launcher library to start/stop Chrome browser programmatically

require('chrome-remote-interface')

Chrome-Remote-Interface library to operate

chromeLauncher.launch

launch Chrome with specified params

CDP(async (client)

init remote debugging interface connection when browser is ready

Page.navigate

go to specified URL

await Page.loadEventFired()

wait while page is loaded

Page.captureScreenshot

make screenshot

screen.png

path to save screenshot to

client.close

close remote debugging interface connection

chrome.kill()

close browser

setTimeout(r, 6000)

wait for 6 seconds before taking screenshot