Airship\Cabin\Bridge\Landing\Admin::notaryDiscovery PHP Method

    protected function notaryDiscovery(string $url) : array
    {
        $state = State::instance();
        if (IDE_HACKS) {
            $state->hail = new Hail(new Client());
        }
        $body = $state->hail->getReturnBody($url);
        $pos = \strpos($body, '<meta name="airship-notary" content="');
        if ($pos === false) {
            // Notary not enabled:
            return [];
        }
        $body = Util::subString($body, $pos + 37);
        $end = \strpos($body, '"');
        if (!$end) {
            // Invalid
            return [];
        }
        $tag = \explode('; ', Util::subString($body, 0, $end));
        $channel = null;
        $notary_url = null;
        foreach ($tag as $t) {
            list($k, $v) = \explode('=', $t);
            if ($k === 'channel') {
                $channel = $v;
            } elseif ($k === 'url') {
                $notary_url = $v;
            }
        }
        return ['public_key' => $tag[0], 'channel' => $channel, 'url' => $notary_url];
    }