SimplePie::get_feed_tags PHP Method

    public function get_feed_tags($namespace, $tag)
    {
        $type = $this->get_type();
        if ($type & SIMPLEPIE_TYPE_ATOM_10) {
            if (isset($this->data['child'][SIMPLEPIE_NAMESPACE_ATOM_10]['feed'][0]['child'][$namespace][$tag])) {
                return $this->data['child'][SIMPLEPIE_NAMESPACE_ATOM_10]['feed'][0]['child'][$namespace][$tag];
            }
        }
        if ($type & SIMPLEPIE_TYPE_ATOM_03) {
            if (isset($this->data['child'][SIMPLEPIE_NAMESPACE_ATOM_03]['feed'][0]['child'][$namespace][$tag])) {
                return $this->data['child'][SIMPLEPIE_NAMESPACE_ATOM_03]['feed'][0]['child'][$namespace][$tag];
            }
        }
        if ($type & SIMPLEPIE_TYPE_RSS_RDF) {
            if (isset($this->data['child'][SIMPLEPIE_NAMESPACE_RDF]['RDF'][0]['child'][$namespace][$tag])) {
                return $this->data['child'][SIMPLEPIE_NAMESPACE_RDF]['RDF'][0]['child'][$namespace][$tag];
            }
        }
        if ($type & SIMPLEPIE_TYPE_RSS_SYNDICATION) {
            if (isset($this->data['child'][SIMPLEPIE_NAMESPACE_RSS_20]['rss'][0]['child'][$namespace][$tag])) {
                return $this->data['child'][SIMPLEPIE_NAMESPACE_RSS_20]['rss'][0]['child'][$namespace][$tag];
            }
        }
        return null;
    }

function discover_by_url($url, $arr = null)
{
    require_once 'library/HTML5/Parser.php';
    $x = scrape_feed($url);
    if (!$x) {
        if (!$arr) {
            return false;
        }
        $network = $arr['network'] ? $arr['network'] : 'unknown';
        $name = $arr['name'] ? $arr['name'] : 'unknown';
        $photo = $arr['photo'] ? $arr['photo'] : '';
        $addr = $arr['addr'] ? $arr['addr'] : '';
        $guid = $url;
    }
    $profile = $url;
    logger('scrape_feed results: ' . print_r($x, true));
    if ($x['feed_atom']) {
        $guid = $x['feed_atom'];
    }
    if ($x['feed_rss']) {
        $guid = $x['feed_rss'];
    }
    if (!$guid) {
        return false;
    }
    // try and discover stuff from the feeed
    require_once 'library/simplepie/simplepie.inc';
    $feed = new SimplePie();
    $level = 0;
    $x = z_fetch_url($guid, false, $level, array('novalidate' => true));
    if (!$x['success']) {
        logger('probe_url: feed fetch failed for ' . $poll);
        return false;
    }
    $xml = $x['body'];
    logger('probe_url: fetch feed: ' . $guid . ' returns: ' . $xml, LOGGER_DATA);
    logger('probe_url: scrape_feed: headers: ' . $x['header'], LOGGER_DATA);
    // Don't try and parse an empty string
    $feed->set_raw_data($xml ? $xml : '<?xml version="1.0" encoding="utf-8" ?><xml></xml>');
    $feed->init();
    if ($feed->error()) {
        logger('probe_url: scrape_feed: Error parsing XML: ' . $feed->error());
    }
    $name = unxmlify(trim($feed->get_title()));
    $photo = $feed->get_image_url();
    $author = $feed->get_author();
    if ($author) {
        if (!$name) {
            $name = unxmlify(trim($author->get_name()));
        }
        if (!$name) {
            $name = trim(unxmlify($author->get_email()));
            if (strpos($name, '@') !== false) {
                $name = substr($name, 0, strpos($name, '@'));
            }
        }
        if (!$profile && $author->get_link()) {
            $profile = trim(unxmlify($author->get_link()));
        }
        if (!$photo) {
            $rawtags = $feed->get_feed_tags(SIMPLEPIE_NAMESPACE_ATOM_10, 'author');
            if ($rawtags) {
                $elems = $rawtags[0]['child'][SIMPLEPIE_NAMESPACE_ATOM_10];
                if (x($elems, 'link') && $elems['link'][0]['attribs']['']['rel'] === 'photo') {
                    $photo = $elems['link'][0]['attribs']['']['href'];
                }
            }
        }
    } else {
        $item = $feed->get_item(0);
        if ($item) {
            $author = $item->get_author();
            if ($author) {
                if (!$name) {
                    $name = trim(unxmlify($author->get_name()));
                    if (!$name) {
                        $name = trim(unxmlify($author->get_email()));
                    }
                    if (strpos($name, '@') !== false) {
                        $name = substr($name, 0, strpos($name, '@'));
                    }
                }
                if (!$profile && $author->get_link()) {
                    $profile = trim(unxmlify($author->get_link()));
                }
            }
            if (!$photo) {
                $rawmedia = $item->get_item_tags('http://search.yahoo.com/mrss/', 'thumbnail');
                if ($rawmedia && $rawmedia[0]['attribs']['']['url']) {
                    $photo = unxmlify($rawmedia[0]['attribs']['']['url']);
                }
            }
            if (!$photo) {
                $rawtags = $item->get_item_tags(SIMPLEPIE_NAMESPACE_ATOM_10, 'author');
                if ($rawtags) {
                    $elems = $rawtags[0]['child'][SIMPLEPIE_NAMESPACE_ATOM_10];
                    if (x($elems, 'link') && $elems['link'][0]['attribs']['']['rel'] === 'photo') {
                        $photo = $elems['link'][0]['attribs']['']['href'];
                    }
                }
            }
        }
    }
    if ($poll === $profile) {
        $lnk = $feed->get_permalink();
    }
    if (isset($lnk) && strlen($lnk)) {
        $profile = $lnk;
    }
    if (!$network) {
        $network = 'rss';
    }
    if (!$name) {
        $name = notags($feed->get_description());
    }
    if (!$guid) {
        return false;
    }
    $r = q("select * from xchan where xchan_hash = '%s' limit 1", dbesc($guid));
    if ($r) {
        return true;
    }
    if (!$photo) {
        $photo = z_root() . '/images/rss_icon.png';
    }
    $r = q("insert into xchan ( xchan_hash, xchan_guid, xchan_pubkey, xchan_addr, xchan_url, xchan_name, xchan_network, xchan_instance_url, xchan_name_date ) values ('%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s') ", dbesc($guid), dbesc($guid), dbesc($pubkey), dbesc($addr), dbesc($profile), dbesc($name), dbesc($network), dbesc(z_root()), dbesc(datetime_convert()));
    $photos = import_xchan_photo($photo, $guid);
    $r = q("update xchan set xchan_photo_date = '%s', xchan_photo_l = '%s', xchan_photo_m = '%s', xchan_photo_s = '%s', xchan_photo_mimetype = '%s' where xchan_hash = '%s'", dbesc(datetime_convert()), dbesc($photos[0]), dbesc($photos[1]), dbesc($photos[2]), dbesc($photos[3]), dbesc($guid));
    return true;
}