how to integrate lighthouse with testcafe?

问题

I need to pass the connection argument while calling lighthouse

https://github.com/GoogleChrome/lighthouse/blob/master/lighthouse-core/index.js#L41

async function lighthouse(url, flags = {}, configJSON, connection) {
  // verify the url is valid and that protocol is allowed
  if (url && (!URL.isValid(url) || !URL.isProtocolAllowed(url))) {
    throw new LHError(LHError.errors.INVALID_URL);
  }

  // set logging preferences, assume quiet
  flags.logLevel = flags.logLevel || 'error';
  log.setLevel(flags.logLevel);

  const config = generateConfig(configJSON, flags);

  connection = connection || new ChromeProtocol(flags.port, flags.hostname);

  // kick off a lighthouse run
  return Runner.run(connection, {url, config});
}

And in my testcafe my tests look like

test('Run lighthouse, async t => {
  lighthouse('https://www.youtube.com', {}, {}, ????)
})

I am unable to retrieve the connection of the chrome instance that testcafe had opened up, instead of spawning a new chromeRunner

回答1:

I did something similar, I launch ligthouse with google chrome on a specific port using CLI

npm run testcafe -- chrome:headless:cdpPort=1234

Then I make the lighthouse function to get port as an argument

export default async function lighthouseAudit(url, browser_port){
    let result = await lighthouse(url, {
        port: browser_port,     // Google Chrome port Number
        output: 'json',
        logLevel: 'info',
    });
    return result;
};

Then you can simply run the audit like

    test(`Generate Light House Result `, async t => {
        auditResult = await lighthouseAudit('https://www.youtube.com',1234);
    });

Hopefully It helps

回答2:

there is an npm library called testcafe-lighthouse which helps to audit web pages using TestCafe. It also has the capability to produce an HTML detailed report.

Install the plugin by:

$ yarn add -D testcafe-lighthouse
# or 
$ npm install --save-dev testcafe-lighthouse

Audit with default threshold

import { testcafeLighthouseAudit } from 'testcafe-lighthouse';

fixture(`Audit Test`).page('http://localhost:3000/login');

test('user performs lighthouse audit', async () => {
  const currentURL = await t.eval(() => document.documentURI);
  await testcafeLighthouseAudit({
    url: currentURL,
    cdpPort: 9222,
  });
});

Audit with custom Thresold:

import { testcafeLighthouseAudit } from 'testcafe-lighthouse';

fixture(`Audit Test`).page('http://localhost:3000/login');

test('user page performance with specific thresholds', async () => {

  const currentURL = await t.eval(() => document.documentURI);

  await testcafeLighthouseAudit({
    url: currentURL,
    thresholds: {
      performance: 50,
      accessibility: 50,
      'best-practices': 50,
      seo: 50,
      pwa: 50,
    },
    cdpPort: 9222,
  });
});

you need to kick start the test like below:

# headless mode, preferable for CI
npx testcafe chrome:headless:cdpPort=9222 test.js

# non headless mode
npx testcafe chrome:emulation:cdpPort=9222   test.js

I hope it will help your automation journey.

来源：https://stackoverflow.com/questions/54863796/how-to-integrate-lighthouse-with-testcafe

标签

google-chrome

audit

testcafe

Lighthouse