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A Karma plugin. Launch any browser on BrowserStack!


Use any browser on BrowserStack!

The easiest way is to keep karma-browserstack-launcher as a devDependency in your package.json. Just run,

$ npm install karma-browserstack-launcher --save-dev

and it will be added automatically.

// karma.conf.js 
module.exports = function(config) {
    // global config of your BrowserStack account 
    browserStack: {
      username: 'jamesbond',
      accessKey: '007'
    // define browsers 
    customLaunchers: {
      bs_firefox_mac: {
        base: 'BrowserStack',
        browser: 'firefox',
        browser_version: '21.0',
        os: 'OS X',
        os_version: 'Mountain Lion'
      bs_iphone5: {
        base: 'BrowserStack',
        device: 'iPhone 5',
        os: 'ios',
        os_version: '6.0'
    browsers: ['bs_firefox_mac', 'bs_iphone5']
  • username your BS username, you can also use BROWSER_STACK_USERNAME env variable.
  • accessKey your BS access key, you can also use BROWSER_STACK_ACCESS_KEY env variable.
  • startTunnel do you wanna establish the BrowserStack tunnel ? (defaults to true)
  • tunnelIdentifier in case you want to start the BrowserStack tunnel outside karma by setting startTunnel to false, set the identifier passed to the -localIdentifier option here (optional)
  • retryLimit how many times do you want to retry to capture the browser ? (defaults to 3)
  • captureTimeout the browser capture timeout (defaults to 120)
  • timeout the BS worker timeout (defaults to 300
  • build the BS worker build name (optional)
  • name the BS worker name (optional)
  • project the BS worker project name (optional)
  • binaryBasePath the BS binary base bath, you can also use BROWSER_STACK_BINARY_BASE_PATH env variable. This will override the default and set the base path to the BS local binary (optional)
  • proxyHost the host of your proxy for communicating with BrowserStack REST API and BrowserStackLocal (optional)
  • proxyPort the port of your proxy (optional)
  • proxyUser the username used for authentication with your proxy (optional)
  • proxyPass the password used for authentication with your proxy (optional)
  • proxyProtocol the protocol of your proxy (optional. default: http. valid: http or https)
  • device name of the device
  • real_mobile allow browserstack to use a simulator
  • browser name of the browser
  • browser_version version of the browser
  • os which platform ?
  • os_version version of the platform

To report session results back to BrowserStack for display on your BrowserStack dashboard, use the following additional configuration:

// karma.conf.js 
module.exports = function(config) {
    // The rest of your karma config is here 
    // ... 
    reporters: ['dots', 'browserStack']

By default, your Selenium and JS tests will run on real iOS devices on BrowserStack. Since we are in the implementation phase, we are still working on a few things, such as adding more devices, ability to test on local URLs, etc.

In case your tests are facing any issues on real iOS devices, we also provide iOS simulators where you can run your automated tests smoothly.

To access our iOS simulators, use the following capabilities:

customLaunchers: {
  iPad_3: {
    real_mobile: false,
    device: 'iPad 3rd (6.0)',
    os: 'ios',
    'os_version': '6.0',
    'browser_version': null,
    browser: 'Mobile Safari'

List of iOS simulators you can test on:

  • device: 'iPad 3rd', 'os_version': '5.1'
  • device: 'iPad 3rd (6.0)', 'os_version': '6.0'
  • device: 'iPad Mini', 'os_version': '7.0'
  • device: 'iPad 4th', 'os_version': '7.0'
  • device: 'iPhone 4S', 'os_version': '5.1'
  • device: 'iPhone 4S (6.0)', 'os_version': '6.0'
  • device: 'iPhone 5', 'os_version': '6.0'
  • device: 'iPhone 5S', 'os_version': '7.0'

Many CI/CD systems will make the name or ID of the currently running build available via an environment variable. The follow environment variables below are supported by default:

  • process.env.BUILD_NUMBER
  • process.env.BUILD_TAG
  • process.env.CI_BUILD_NUMBER
  • process.env.CI_BUILD_TAG
  • process.env.TRAVIS_BUILD_NUMBER
  • process.env.CIRCLE_BUILD_NUM
  • process.env.DRONE_BUILD_NUMBER

BrowserStack's REST API documentation explains how to retrieve a list of desired capabilities for browsers.

For more information on Karma see the homepage.

Check out sample code working with karma-browserstack-launcher here.