docs: def start(cls, ev=None):
          """
          Start the analysis.
          """
          ViewController.log_view.add("Beginning AnalysisRunner request..")
  
          # reset all inputs
          ViewController.reset_bars()
  
          # read the urlbox
          url = ViewController.url.strip()
  
          # make sure, that `url` was filled
          if not url:
              ViewController.urlbox_error.show("URL musí být vyplněna.")
              return
  
          if is_issn(url):
              ViewController.url_progressbar.hide()
              ViewController.url = ""
              ViewController.issn = url
              AlephISSNReaderAdapter.start()
              return
  
          ViewController.urlbox_error.hide()
  
          # normalize the `url`
          if not (url.startswith("http://") or url.startswith("https://")):
              url = "http://" + url
              ViewController.url = url  # store normalized url back to input
  
          make_request(
              url=join(settings.API_PATH, "analyze"),
              data={'url': url},
              on_complete=cls.on_complete
          )