karma-webkit-launcher

karma-webkit-launcher

Karma Launcher for Apple's Webkit

Installation

The easiest way is to keep karma-webkit-launcher as a devDependency in your package.json, by running

npm install karma-webkit-launcher --save-dev

Supported WebKit-Launcher

This karma-webkit-launcher provides the following browser launcher.

Karma Runner Browsers	ENV	Type	CI note
WebKit	WEBKIT_BIN	Native / Playwright / Safari (MacOS only)	-
WebKitHeadless	WEBKIT_HEADLESS_BIN	Native / Playwright	-
Safari	SAFARI_BIN	Native MacOS only	not supported
Epiphany	EPIPHANY_BIN	Native Ubuntu only	needs xvfb-run

Configuration

For the configuration just add Webkit or WebkitHeadless in your browser list.

// karma.conf.js
export default (config) => {
  config.set({
    browsers: ['Webkit'],  // You may use 'WebkitHeadless' or other supported browser

You can pass the list of browsers as a CLI argument too:

karma start --browsers Webkit

Headless Webkit with Playwright / Playwright-Webkit

Playwright is a Node.js library to automate Chromium, Firefox and WebKit with a single API. Playwright is built to enable cross-browser web automation that is ever-green, capable, reliable and fast.

Headless execution is supported for all the browsers on all platforms. Check out system requirements for details.

If no environment variable is set and Playwright is available, it will be automatically utilized. Additionally, if you exclusively intend to perform WebKit testing, you can install 'playwright-webkit' exclusively for that purpose.

Example Usage

Installing Playwright and karma-webkit-launcher

npm install playwright karma-webkit-launcher --save-dev

Example Karma configuration

// karma.conf.js
module.exports = function (config) {
  config.set({
    browsers: ["WebkitHeadless"],
  });
};

Manually define Playwright executable

To force the use of Playwright over an local Webkit instance, just overwrite the WEBKIT_HEADLESS_BIN or WEBKIT_BIN environment variable.

// karma.conf.js
import playwright from "playwright";
process.env.WEBKIT_HEADLESS_BIN = playwright.webkit.executablePath();

module.exports = function (config) {
  config.set({
    browsers: ["WebkitHeadless"],
  });
};

Advanced Topics

Detected if Safari or Playwright is used

In some instances it is helpful to detect if Playwright or a real Safari Browser is used. For this reason it's possible to detect which kind of browser is currently running the tests over this runner.

if (
  new URLSearchParams(document.referrer || window.location.search).get(
    "test_browser"
  ) == "Playwright"
) {
  // Playwright specific tests
}

See: Playwright Karma Test

if (
  new URLSearchParams(document.referrer || window.location.search).get(
    "test_browser"
  ) == "Safari"
) {
  // Safari specific tests
}

See: Safari Karma Test

For more information on Karma see the Karma Homepage.