export function start()

in src/lib/api/event.recorder.ts [52:102]
31 lines of code
11 McCabe index (conditional complexity)

export function start(prebootData: PrebootData, win?: PrebootWindow) {
  const theWindow = <PrebootWindow>(win || window);
  const _document = <Document>(theWindow.document || {});

  // Remove the current script from the DOM so that child indexes match
  // between the client & the server. The script is already running so it
  // doesn't affect it.
  const currentScript = _document.currentScript ||
    // Support: IE 9-11 only
    // IE doesn't support document.currentScript. Since the script is invoked
    // synchronously, though, the current running script is just the last one
    // currently in the document.
    [].slice.call(_document.getElementsByTagName('script'), -1)[0];

  if (!currentScript) {
    console.error('Preboot initialization failed, no currentScript has been detected.');
    return;
  }

  let serverNode = currentScript.parentNode;
  if (!serverNode) {
    console.error('Preboot initialization failed, the script is detached');
    return;
  }

  serverNode.removeChild(currentScript);

  const opts = prebootData.opts || ({} as PrebootOptions);
  let eventSelectors = opts.eventSelectors || [];

  // get the root info
  const appRoot = prebootData.opts ? getAppRoot(_document, prebootData.opts, serverNode) : null;

  // we track all events for each app in the prebootData object which is on
  // the global scope; each `start` invocation adds data for one app only.
  const appData = <PrebootAppData>{ root: appRoot, events: [] };
  if (prebootData.apps) {
    prebootData.apps.push(appData);
  }

  eventSelectors = eventSelectors.map(eventSelector => {
    if (!eventSelector.hasOwnProperty('replay')) {
      eventSelector.replay = true;
    }
    return eventSelector;
  });

  // loop through all the eventSelectors and create event handlers
  eventSelectors.forEach(eventSelector =>
    handleEvents(_document, prebootData, appData, eventSelector));
}