karma-local-wd-launcher

karma-local-wd-launcher

Karma Local WebDriver Launcher

Launches local web browsers using WebDriver, to enable screenshots and other advanced tests to be executed in-browser. If you don't need WebDriver to enable some test scenario in Karma, you can just use typical local browser launchers.

Supports Chrome, Firefox, Edge, and Safari.

Installation

npm install --save-dev karma-local-wd-launcher

Drivers

This launcher will use the webdriver-installer module to automatically download and install driver binaries for your local browsers. These will be cached in a folder called .webdriver-installer-cache in your home directory.

Alternately, you may use the environment variables CHROMEDRIVER_PATH, GECKODRIVER_PATH, or SAFARIDRIVER_PATH to indicate where these drivers are already installed.

Configuration

// karma.conf.js
module.exports = (config) => {
  config.set({
    plugins: ['karma-local-wd-launcher'],
    browsers: ['Chrome', 'Firefox', 'Edge', 'Safari'],
  });
};

You can give Karma's command-line interface a list of browsers, too:

karma start --browsers Chrome Firefox Safari

There is a possibilty to create custom launcher based on existing ones, i.e. to pass additional configuration options to specific WebDriver.

// karma.conf.js
module.exports = (config) => {
  config.set({
    customLaunchers: {
      'ChromeNoBackgroundSuspend': {
        base: 'Chrome',
        config: {
          'goog:chromeOptions': {
            args: [
              '--disable-background-media-suspend',
              '--disable-background-timer-throttling',
              '--disable-backgrounding-occluded-windows',
            ],
          },
        },
      },
    },
  });
};

Changelog

1.7.2 (2025-07-16)

Bug Fixes

• Fix msedgedriver install (#92) (c34f693)