Performance Audit by Quave

Easily check the performance of a web address according to Google's PageSpeed and compare with an expected baseline. To know more about the scores, see https://developers.google.com/web/tools/lighthouse. This test is designed to run on a CI to monitor the scores over time and notify when a regression occurs.

Installation

npm install @quave/performance-audit

How to use

Pass a array of tests to the checkPerformance function.

Test object structure:

• url: The link to test
• stategy: Should be desktop or mobile
• threshold: How much the results need to differ to trigger a fail
• pwa, bestPractices, accessibility, seo, performance: Scores baselines for the tests (optional)
• appJsTransferSize, appCssTransferSize: Sizes baselines of the js and css bundles (optional)
• jsIdentifier, cssIdentifier: String used to identify your app's bundle. (required if using appJsTransferSize or appCssTrasnferSize)

Additionally, you may pass a options as a second argument, to use values commom for all tests.

Example

// Example file app.slow.test.js
import { checkPerformance } from "@quave/performance-audit";

checkPerformance({
  applications: [
    {
      url: "https://www.meteor.com",
      strategy: "desktop",
      pwa: 0.69,
      bestPractices: 0.77,
      accessibility: 0.55,
      seo: 0.6,
      performance: 0.2,
      appJsTransferSize: 2168542,
      appCssTransferSize: 4513,
    },
  ],
  options: {
    threshold: 0.95,
    jsIdentifier: '.js?meteor_js_resource=true',
    cssIdentifier: '.css?meteor_css_resource=true',
  },
)

Jest

The library uses jest to run the test. It is set as a peer dependency, so you may choose which version to install.

Slow tests

This test usually takes several seconds to complete, and that is not great. We recommend creating a new test group e.g. slow group:

//File jest.slow.config.js
module.exports = {
  ...
  testRegex: '(/__tests__/.*|(\\.|/)(slow\\.test))\\.jsx?$',
  ...
};

And then creating the performance tests in a file with the suffix slow.test.js. These tests then can be executed by calling jest -c jest.slow.config.js.