How long does a video page take to load

measure_video_load.js

// npm install puppeteer
// node measure_video_load.js https://digital.library.jhu.edu/islandora/dumb-show
const puppeteer = require('puppeteer');

(async () => {
  // Get the URL from command-line arguments
  const url = process.argv[2]; // The URL is the third argument in the command line (0 = node, 1 = script name, 2 = URL)

  if (!url) {
    console.error('Please provide a URL as an argument.');
    process.exit(1); // Exit the script if no URL is provided
  }

  const browser = await puppeteer.launch({ headless: false }); // Keep headless as false for debugging
  const page = await browser.newPage();

  try {
    // Navigate to the provided URL and wait until the network is idle
    await page.goto(url, { waitUntil: 'networkidle2', timeout: 120000 });

    // Wait for the video element to appear
    await page.waitForSelector('video', { timeout: 60000 });

    // Measure the time it takes for the video to load fully
    const videoLoadTime = await page.evaluate(() => {
      return new Promise((resolve) => {
        const video = document.querySelector('video');
        const loadStartTime = performance.now();

        // Listen for the 'canplaythrough' event to ensure video is fully loaded
        video.addEventListener('canplaythrough', () => {
          const loadEndTime = performance.now();
          const loadDuration = loadEndTime - loadStartTime;
          resolve(loadDuration);
        });

        // Set the video source and trigger the loading
        video.load();
      });
    });

    console.log(`Video Load Time for ${url}: ${videoLoadTime}ms`);
  } catch (error) {
    console.error('Error occurred while waiting for video to load:', error);
  }

  await browser.close();
})();