Karma custom configuration for PhantomJs (allowing screen size, screenshot, ...)

karma.conf.js

'use strict';

module.exports = function (config) {
  config.set({
    // ...
    'browsers': ['PhantomJSCustom'],
    'customLaunchers': {
      'PhantomJSCustom': {
        'base': 'PhantomJS',
        'options': {
          'windowName': 'my-window',
          'settings': {
            'webSecurityEnabled': false
          },
          'viewportSize': {
            'width': 1920,
            'height': 1080
          },
          'flags': ['--load-images=true'],
          'debug': false,
          'onCallback': function (data) {
            // For screenshot: to use it into the tests: window.top.callPhantom({type: 'render'});
            if (data.type === 'render') {
              // This function will not have the scope of karma.conf.js so we must define any global variable inside it
              if (window.renderId === undefined) {
                window.renderId = 0;
              }

              page.render('./target/screenshot_' + (window.renderId++) + '.png');
            }
          }
        }
      }
    }
    // ...
  });
};