Start the analysis.

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
        )