Throttle network speed via Playwright CDPSession

throttle-network-speed.spec.ts

// See also https://chromedevtools.github.io/devtools-protocol/tot/Network/#method-emulateNetworkConditions

import { test, chromium } from '@playwright/test';

test("throttle network speed to 2.1 Mbps", async ({ }) => {
  const browser = await chromium.launchPersistentContext("");
  const page = await browser.newPage();
  const client = await page.context().newCDPSession(page);
  await client.send("Network.enable");
  await client.send("Network.emulateNetworkConditions", {
    offline: false,
    downloadThroughput: (2 * 1024 * 1024) / 8,
    uploadThroughput: (2 * 1024 * 1024) / 8,
    latency: 70,
  });
  await page.goto("https://fast.com/");
  await page.waitForTimeout(4000);
});