karma-firefox-launcher

What is karma-firefox-launcher?

The karma-firefox-launcher is a plugin for the Karma test runner that allows you to run your tests in the Firefox browser. It provides seamless integration with Karma, enabling automated testing in Firefox as part of your continuous integration pipeline.

What are karma-firefox-launcher's main functionalities?

Launching Firefox for Testing

This configuration file for Karma sets up the test runner to use the Firefox browser. It specifies the use of the Jasmine framework and includes the necessary plugins for both Jasmine and the Firefox launcher.

module.exports = function(config) {
  config.set({
    browsers: ['Firefox'],
    frameworks: ['jasmine'],
    files: [
      'test/**/*.spec.js'
    ],
    plugins: [
      'karma-jasmine',
      'karma-firefox-launcher'
    ]
  });
};

Customizing Firefox Launch Options

This configuration demonstrates how to set up a custom launcher for Firefox in headless mode. This is useful for running tests in environments where you don't have a display, such as in a CI/CD pipeline.

module.exports = function(config) {
  config.set({
    browsers: ['Firefox'],
    customLaunchers: {
      FirefoxHeadless: {
        base: 'Firefox',
        flags: ['-headless']
      }
    },
    frameworks: ['jasmine'],
    files: [
      'test/**/*.spec.js'
    ],
    plugins: [
      'karma-jasmine',
      'karma-firefox-launcher'
    ]
  });
};

Other packages similar to karma-firefox-launcher

karma-chrome-launcher

The karma-chrome-launcher is a plugin for the Karma test runner that allows you to run your tests in the Chrome browser. Similar to karma-firefox-launcher, it provides seamless integration with Karma and supports both regular and headless modes for Chrome.

karma-safari-launcher

The karma-safari-launcher is a plugin for the Karma test runner that allows you to run your tests in the Safari browser. It offers similar functionality to karma-firefox-launcher but is tailored for the Safari browser, making it useful for testing on macOS environments.

karma-edge-launcher

The karma-edge-launcher is a plugin for the Karma test runner that allows you to run your tests in the Microsoft Edge browser. Like karma-firefox-launcher, it integrates with Karma to facilitate automated testing in Edge, supporting both legacy and Chromium-based versions of the browser.

README

karma-firefox-launcher

Launcher for Mozilla Firefox.

Installation

The easiest way is to keep karma-firefox-launcher as a devDependency in your package.json.

You can simple do it by:

npm install karma-firefox-launcher --save-dev

Configuration

// karma.conf.js
module.exports = function(config) {
  config.set({
    browsers: ['Firefox', 'FirefoxDeveloper', 'FirefoxAurora', 'FirefoxNightly'],
  })
}

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

karma start --browsers Firefox,Chrome

To run Firefox in headless mode, append Headless to the version name, e.g. FirefoxHeadless, FirefoxNightlyHeadless.

Environment variables

You can specify the location of the Firefox executable using the following environment variables:

• FIREFOX_BIN (for browser Firefox or FirefoxHeadless)
• FIREFOX_DEVELOPER_BIN (for browser FirefoxDeveloper or FirefoxDeveloperHeadless)
• FIREFOX_AURORA_BIN (for browser FirefoxAurora or FirefoxAuroraHeadless)
• FIREFOX_NIGHTLY_BIN (for browser FirefoxNightly or FirefoxNightlyHeadless)

Custom Firefox location

In addition to Environment variables you can specify location of the Firefox executable in a custom launcher:

browsers: ['Firefox68', 'Firefox78'],

customLaunchers: {
    Firefox68: {
        base: 'Firefox',
        name: 'Firefox68',
        command: '<path to FF68>/firefox.exe'
    },
    Firefox78: {
        base: 'Firefox',
        name: 'Firefox78',
        command: '<path to FF78>/firefox.exe'
    }
}

Custom Preferences

To configure preferences for the Firefox instance that is loaded, you can specify a custom launcher in your Karma config with the preferences under the prefs key:

browsers: ['FirefoxAutoAllowGUM'],

customLaunchers: {
    FirefoxAutoAllowGUM: {
        base: 'Firefox',
        prefs: {
            'media.navigator.permission.disabled': true
        }
    }
}

Loading Firefox Extensions

If you have extensions that you want loaded into the browser on startup, you can specify the full path to each extension in the extensions key:

browsers: ['FirefoxWithMyExtension'],

customLaunchers: {
    FirefoxWithMyExtension: {
        base: 'Firefox',
        extensions: [
          path.resolve(__dirname, 'helpers/extensions/[e-mail]'),
          path.resolve(__dirname, 'helpers/extensions/[e-mail]')
        ]
    }
}

Please note: the extension name must exactly match the 'id' of the extension. You can discover the 'id' of your extension by extracting the .xpi (i.e. unzip XXX.xpi) and opening the install.RDF file with a text editor, then look for the em:id tag under the Description tag. If your extension manifest looks something like this:

<?xml version="1.0" encoding="utf-8"?>
   <RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:em="http://www.mozilla.org/2004/em-rdf#">
  <Description about="urn:mozilla:install-manifest">
    <em:id>myCustomExt@suchandsuch</em:id>
    <em:version>1.0</em:version>
    <em:type>2</em:type>
    <em:bootstrap>true</em:bootstrap>
    <em:unpack>false</em:unpack>

    [...]
  </Description>
</RDF>

Then you should name your extension [e-mail].

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For more information on Karma see the homepage.

Changelog

2.1.2 (2021-11-02)

Bug Fixes

• launcher does not kill firefox.exe on WSL (3954ad4), closes /github.com/karma-runner/karma-firefox-launcher/issues/101#issuecomment-891850143