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    <h3>Editing: SimplePie.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

/**
 * SimplePie
 *
 * A PHP-Based RSS and Atom Feed Framework.
 * Takes the hard work out of managing a complete RSS/Atom solution.
 *
 * Copyright (c) 2004-2022, Ryan Parman, Sam Sneddon, Ryan McCue, and contributors
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
 *
 * 	* Redistributions of source code must retain the above copyright notice, this list of
 * 	  conditions and the following disclaimer.
 *
 * 	* Redistributions in binary form must reproduce the above copyright notice, this list
 * 	  of conditions and the following disclaimer in the documentation and/or other materials
 * 	  provided with the distribution.
 *
 * 	* Neither the name of the SimplePie Team nor the names of its contributors may be used
 * 	  to endorse or promote products derived from this software without specific prior
 * 	  written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS &quot;AS IS&quot; AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
 * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @package SimplePie
 * @copyright 2004-2016 Ryan Parman, Sam Sneddon, Ryan McCue
 * @author Ryan Parman
 * @author Sam Sneddon
 * @author Ryan McCue
 * @link http://simplepie.org/ SimplePie
 * @license http://www.opensource.org/licenses/bsd-license.php BSD License
 */

namespace SimplePie;

use InvalidArgumentException;
use Psr\SimpleCache\CacheInterface;
use SimplePie\Cache\Base;
use SimplePie\Cache\BaseDataCache;
use SimplePie\Cache\CallableNameFilter;
use SimplePie\Cache\DataCache;
use SimplePie\Cache\NameFilter;
use SimplePie\Cache\Psr16;
use SimplePie\Content\Type\Sniffer;

/**
 * SimplePie
 *
 * @package SimplePie
 * @subpackage API
 */
class SimplePie
{
    /**
     * SimplePie Name
     */
    public const NAME = 'SimplePie';

    /**
     * SimplePie Version
     */
    public const VERSION = '1.8.0';

    /**
     * SimplePie Website URL
     */
    public const URL = 'http://simplepie.org';

    /**
     * SimplePie Linkback
     */
    public const LINKBACK = '&lt;a href=&quot;' . self::URL . '&quot; title=&quot;' . self::NAME . ' ' . self::VERSION . '&quot;&gt;' . self::NAME . '&lt;/a&gt;';

    /**
     * No Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_NONE = 0;

    /**
     * Feed Link Element Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_AUTODISCOVERY = 1;

    /**
     * Local Feed Extension Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_LOCAL_EXTENSION = 2;

    /**
     * Local Feed Body Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_LOCAL_BODY = 4;

    /**
     * Remote Feed Extension Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_REMOTE_EXTENSION = 8;

    /**
     * Remote Feed Body Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_REMOTE_BODY = 16;

    /**
     * All Feed Autodiscovery
     * @see SimplePie::set_autodiscovery_level()
     */
    public const LOCATOR_ALL = 31;

    /**
     * No known feed type
     */
    public const TYPE_NONE = 0;

    /**
     * RSS 0.90
     */
    public const TYPE_RSS_090 = 1;

    /**
     * RSS 0.91 (Netscape)
     */
    public const TYPE_RSS_091_NETSCAPE = 2;

    /**
     * RSS 0.91 (Userland)
     */
    public const TYPE_RSS_091_USERLAND = 4;

    /**
     * RSS 0.91 (both Netscape and Userland)
     */
    public const TYPE_RSS_091 = 6;

    /**
     * RSS 0.92
     */
    public const TYPE_RSS_092 = 8;

    /**
     * RSS 0.93
     */
    public const TYPE_RSS_093 = 16;

    /**
     * RSS 0.94
     */
    public const TYPE_RSS_094 = 32;

    /**
     * RSS 1.0
     */
    public const TYPE_RSS_10 = 64;

    /**
     * RSS 2.0
     */
    public const TYPE_RSS_20 = 128;

    /**
     * RDF-based RSS
     */
    public const TYPE_RSS_RDF = 65;

    /**
     * Non-RDF-based RSS (truly intended as syndication format)
     */
    public const TYPE_RSS_SYNDICATION = 190;

    /**
     * All RSS
     */
    public const TYPE_RSS_ALL = 255;

    /**
     * Atom 0.3
     */
    public const TYPE_ATOM_03 = 256;

    /**
     * Atom 1.0
     */
    public const TYPE_ATOM_10 = 512;

    /**
     * All Atom
     */
    public const TYPE_ATOM_ALL = 768;

    /**
     * All feed types
     */
    public const TYPE_ALL = 1023;

    /**
     * No construct
     */
    public const CONSTRUCT_NONE = 0;

    /**
     * Text construct
     */
    public const CONSTRUCT_TEXT = 1;

    /**
     * HTML construct
     */
    public const CONSTRUCT_HTML = 2;

    /**
     * XHTML construct
     */
    public const CONSTRUCT_XHTML = 4;

    /**
     * base64-encoded construct
     */
    public const CONSTRUCT_BASE64 = 8;

    /**
     * IRI construct
     */
    public const CONSTRUCT_IRI = 16;

    /**
     * A construct that might be HTML
     */
    public const CONSTRUCT_MAYBE_HTML = 32;

    /**
     * All constructs
     */
    public const CONSTRUCT_ALL = 63;

    /**
     * Don't change case
     */
    public const SAME_CASE = 1;

    /**
     * Change to lowercase
     */
    public const LOWERCASE = 2;

    /**
     * Change to uppercase
     */
    public const UPPERCASE = 4;

    /**
     * PCRE for HTML attributes
     */
    public const PCRE_HTML_ATTRIBUTE = '((?:[\x09\x0A\x0B\x0C\x0D\x20]+[^\x09\x0A\x0B\x0C\x0D\x20\x2F\x3E][^\x09\x0A\x0B\x0C\x0D\x20\x2F\x3D\x3E]*(?:[\x09\x0A\x0B\x0C\x0D\x20]*=[\x09\x0A\x0B\x0C\x0D\x20]*(?:&quot;(?:[^&quot;]*)&quot;|\'(?:[^\']*)\'|(?:[^\x09\x0A\x0B\x0C\x0D\x20\x22\x27\x3E][^\x09\x0A\x0B\x0C\x0D\x20\x3E]*)?))?)*)[\x09\x0A\x0B\x0C\x0D\x20]*';

    /**
     * PCRE for XML attributes
     */
    public const PCRE_XML_ATTRIBUTE = '((?:\s+(?:(?:[^\s:]+:)?[^\s:]+)\s*=\s*(?:&quot;(?:[^&quot;]*)&quot;|\'(?:[^\']*)\'))*)\s*';

    /**
     * XML Namespace
     */
    public const NAMESPACE_XML = 'http://www.w3.org/XML/1998/namespace';

    /**
     * Atom 1.0 Namespace
     */
    public const NAMESPACE_ATOM_10 = 'http://www.w3.org/2005/Atom';

    /**
     * Atom 0.3 Namespace
     */
    public const NAMESPACE_ATOM_03 = 'http://purl.org/atom/ns#';

    /**
     * RDF Namespace
     */
    public const NAMESPACE_RDF = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';

    /**
     * RSS 0.90 Namespace
     */
    public const NAMESPACE_RSS_090 = 'http://my.netscape.com/rdf/simple/0.9/';

    /**
     * RSS 1.0 Namespace
     */
    public const NAMESPACE_RSS_10 = 'http://purl.org/rss/1.0/';

    /**
     * RSS 1.0 Content Module Namespace
     */
    public const NAMESPACE_RSS_10_MODULES_CONTENT = 'http://purl.org/rss/1.0/modules/content/';

    /**
     * RSS 2.0 Namespace
     * (Stupid, I know, but I'm certain it will confuse people less with support.)
     */
    public const NAMESPACE_RSS_20 = '';

    /**
     * DC 1.0 Namespace
     */
    public const NAMESPACE_DC_10 = 'http://purl.org/dc/elements/1.0/';

    /**
     * DC 1.1 Namespace
     */
    public const NAMESPACE_DC_11 = 'http://purl.org/dc/elements/1.1/';

    /**
     * W3C Basic Geo (WGS84 lat/long) Vocabulary Namespace
     */
    public const NAMESPACE_W3C_BASIC_GEO = 'http://www.w3.org/2003/01/geo/wgs84_pos#';

    /**
     * GeoRSS Namespace
     */
    public const NAMESPACE_GEORSS = 'http://www.georss.org/georss';

    /**
     * Media RSS Namespace
     */
    public const NAMESPACE_MEDIARSS = 'http://search.yahoo.com/mrss/';

    /**
     * Wrong Media RSS Namespace. Caused by a long-standing typo in the spec.
     */
    public const NAMESPACE_MEDIARSS_WRONG = 'http://search.yahoo.com/mrss';

    /**
     * Wrong Media RSS Namespace #2. New namespace introduced in Media RSS 1.5.
     */
    public const NAMESPACE_MEDIARSS_WRONG2 = 'http://video.search.yahoo.com/mrss';

    /**
     * Wrong Media RSS Namespace #3. A possible typo of the Media RSS 1.5 namespace.
     */
    public const NAMESPACE_MEDIARSS_WRONG3 = 'http://video.search.yahoo.com/mrss/';

    /**
     * Wrong Media RSS Namespace #4. New spec location after the RSS Advisory Board takes it over, but not a valid namespace.
     */
    public const NAMESPACE_MEDIARSS_WRONG4 = 'http://www.rssboard.org/media-rss';

    /**
     * Wrong Media RSS Namespace #5. A possible typo of the RSS Advisory Board URL.
     */
    public const NAMESPACE_MEDIARSS_WRONG5 = 'http://www.rssboard.org/media-rss/';

    /**
     * iTunes RSS Namespace
     */
    public const NAMESPACE_ITUNES = 'http://www.itunes.com/dtds/podcast-1.0.dtd';

    /**
     * XHTML Namespace
     */
    public const NAMESPACE_XHTML = 'http://www.w3.org/1999/xhtml';

    /**
     * IANA Link Relations Registry
     */
    public const IANA_LINK_RELATIONS_REGISTRY = 'http://www.iana.org/assignments/relation/';

    /**
     * No file source
     */
    public const FILE_SOURCE_NONE = 0;

    /**
     * Remote file source
     */
    public const FILE_SOURCE_REMOTE = 1;

    /**
     * Local file source
     */
    public const FILE_SOURCE_LOCAL = 2;

    /**
     * fsockopen() file source
     */
    public const FILE_SOURCE_FSOCKOPEN = 4;

    /**
     * cURL file source
     */
    public const FILE_SOURCE_CURL = 8;

    /**
     * file_get_contents() file source
     */
    public const FILE_SOURCE_FILE_GET_CONTENTS = 16;

    /**
     * @var array Raw data
     * @access private
     */
    public $data = [];

    /**
     * @var mixed Error string
     * @access private
     */
    public $error;

    /**
     * @var int HTTP status code
     * @see SimplePie::status_code()
     * @access private
     */
    public $status_code = 0;

    /**
     * @var object Instance of \SimplePie\Sanitize (or other class)
     * @see SimplePie::set_sanitize_class()
     * @access private
     */
    public $sanitize;

    /**
     * @var string SimplePie Useragent
     * @see SimplePie::set_useragent()
     * @access private
     */
    public $useragent = '';

    /**
     * @var string Feed URL
     * @see SimplePie::set_feed_url()
     * @access private
     */
    public $feed_url;

    /**
     * @var string Original feed URL, or new feed URL iff HTTP 301 Moved Permanently
     * @see SimplePie::subscribe_url()
     * @access private
     */
    public $permanent_url = null;

    /**
     * @var object Instance of \SimplePie\File to use as a feed
     * @see SimplePie::set_file()
     * @access private
     */
    public $file;

    /**
     * @var string Raw feed data
     * @see SimplePie::set_raw_data()
     * @access private
     */
    public $raw_data;

    /**
     * @var int Timeout for fetching remote files
     * @see SimplePie::set_timeout()
     * @access private
     */
    public $timeout = 10;

    /**
     * @var array Custom curl options
     * @see SimplePie::set_curl_options()
     * @access private
     */
    public $curl_options = [];

    /**
     * @var bool Forces fsockopen() to be used for remote files instead
     * of cURL, even if a new enough version is installed
     * @see SimplePie::force_fsockopen()
     * @access private
     */
    public $force_fsockopen = false;

    /**
     * @var bool Force the given data/URL to be treated as a feed no matter what
     * it appears like
     * @see SimplePie::force_feed()
     * @access private
     */
    public $force_feed = false;

    /**
     * @var bool Enable/Disable Caching
     * @see SimplePie::enable_cache()
     * @access private
     */
    private $enable_cache = true;

    /**
     * @var DataCache|null
     * @see SimplePie::set_cache()
     */
    private $cache = null;

    /**
     * @var NameFilter
     * @see SimplePie::set_cache_namefilter()
     */
    private $cache_namefilter;

    /**
     * @var bool Force SimplePie to fallback to expired cache, if enabled,
     * when feed is unavailable.
     * @see SimplePie::force_cache_fallback()
     * @access private
     */
    public $force_cache_fallback = false;

    /**
     * @var int Cache duration (in seconds)
     * @see SimplePie::set_cache_duration()
     * @access private
     */
    public $cache_duration = 3600;

    /**
     * @var int Auto-discovery cache duration (in seconds)
     * @see SimplePie::set_autodiscovery_cache_duration()
     * @access private
     */
    public $autodiscovery_cache_duration = 604800; // 7 Days.

    /**
     * @var string Cache location (relative to executing script)
     * @see SimplePie::set_cache_location()
     * @access private
     */
    public $cache_location = './cache';

    /**
     * @var string Function that creates the cache filename
     * @see SimplePie::set_cache_name_function()
     * @access private
     */
    public $cache_name_function = 'md5';

    /**
     * @var bool Reorder feed by date descending
     * @see SimplePie::enable_order_by_date()
     * @access private
     */
    public $order_by_date = true;

    /**
     * @var mixed Force input encoding to be set to the follow value
     * (false, or anything type-cast to false, disables this feature)
     * @see SimplePie::set_input_encoding()
     * @access private
     */
    public $input_encoding = false;

    /**
     * @var int Feed Autodiscovery Level
     * @see SimplePie::set_autodiscovery_level()
     * @access private
     */
    public $autodiscovery = self::LOCATOR_ALL;

    /**
     * Class registry object
     *
     * @var \SimplePie\Registry
     */
    public $registry;

    /**
     * @var int Maximum number of feeds to check with autodiscovery
     * @see SimplePie::set_max_checked_feeds()
     * @access private
     */
    public $max_checked_feeds = 10;

    /**
     * @var array All the feeds found during the autodiscovery process
     * @see SimplePie::get_all_discovered_feeds()
     * @access private
     */
    public $all_discovered_feeds = [];

    /**
     * @var string Web-accessible path to the handler_image.php file.
     * @see SimplePie::set_image_handler()
     * @access private
     */
    public $image_handler = '';

    /**
     * @var array Stores the URLs when multiple feeds are being initialized.
     * @see SimplePie::set_feed_url()
     * @access private
     */
    public $multifeed_url = [];

    /**
     * @var array Stores SimplePie objects when multiple feeds initialized.
     * @access private
     */
    public $multifeed_objects = [];

    /**
     * @var array Stores the get_object_vars() array for use with multifeeds.
     * @see SimplePie::set_feed_url()
     * @access private
     */
    public $config_settings = null;

    /**
     * @var integer Stores the number of items to return per-feed with multifeeds.
     * @see SimplePie::set_item_limit()
     * @access private
     */
    public $item_limit = 0;

    /**
     * @var bool Stores if last-modified and/or etag headers were sent with the
     * request when checking a feed.
     */
    public $check_modified = false;

    /**
     * @var array Stores the default attributes to be stripped by strip_attributes().
     * @see SimplePie::strip_attributes()
     * @access private
     */
    public $strip_attributes = ['bgsound', 'class', 'expr', 'id', 'style', 'onclick', 'onerror', 'onfinish', 'onmouseover', 'onmouseout', 'onfocus', 'onblur', 'lowsrc', 'dynsrc'];

    /**
     * @var array Stores the default attributes to add to different tags by add_attributes().
     * @see SimplePie::add_attributes()
     * @access private
     */
    public $add_attributes = ['audio' =&gt; ['preload' =&gt; 'none'], 'iframe' =&gt; ['sandbox' =&gt; 'allow-scripts allow-same-origin'], 'video' =&gt; ['preload' =&gt; 'none']];

    /**
     * @var array Stores the default tags to be stripped by strip_htmltags().
     * @see SimplePie::strip_htmltags()
     * @access private
     */
    public $strip_htmltags = ['base', 'blink', 'body', 'doctype', 'embed', 'font', 'form', 'frame', 'frameset', 'html', 'iframe', 'input', 'marquee', 'meta', 'noscript', 'object', 'param', 'script', 'style'];

    /**
     * @var array Stores the default attributes to be renamed by rename_attributes().
     * @see SimplePie::rename_attributes()
     * @access private
     */
    public $rename_attributes = [];

    /**
     * @var bool Should we throw exceptions, or use the old-style error property?
     * @access private
     */
    public $enable_exceptions = false;

    /**
     * The SimplePie class contains feed level data and options
     *
     * To use SimplePie, create the SimplePie object with no parameters. You can
     * then set configuration options using the provided methods. After setting
     * them, you must initialise the feed using $feed-&gt;init(). At that point the
     * object's methods and properties will be available to you.
     *
     * Previously, it was possible to pass in the feed URL along with cache
     * options directly into the constructor. This has been removed as of 1.3 as
     * it caused a lot of confusion.
     *
     * @since 1.0 Preview Release
     */
    public function __construct()
    {
        if (version_compare(PHP_VERSION, '7.2', '&lt;')) {
            exit('Please upgrade to PHP 7.2 or newer.');
        }

        $this-&gt;set_useragent();

        $this-&gt;set_cache_namefilter(new CallableNameFilter($this-&gt;cache_name_function));

        // Other objects, instances created here so we can set options on them
        $this-&gt;sanitize = new \SimplePie\Sanitize();
        $this-&gt;registry = new \SimplePie\Registry();

        if (func_num_args() &gt; 0) {
            trigger_error('Passing parameters to the constructor is no longer supported. Please use set_feed_url(), set_cache_location(), and set_cache_duration() directly.', \E_USER_DEPRECATED);

            $args = func_get_args();
            switch (count($args)) {
                case 3:
                    $this-&gt;set_cache_duration($args[2]);
                    // no break
                case 2:
                    $this-&gt;set_cache_location($args[1]);
                    // no break
                case 1:
                    $this-&gt;set_feed_url($args[0]);
                    $this-&gt;init();
            }
        }
    }

    /**
     * Used for converting object to a string
     */
    public function __toString()
    {
        return md5(serialize($this-&gt;data));
    }

    /**
     * Remove items that link back to this before destroying this object
     */
    public function __destruct()
    {
        if (!gc_enabled()) {
            if (!empty($this-&gt;data['items'])) {
                foreach ($this-&gt;data['items'] as $item) {
                    $item-&gt;__destruct();
                }
                unset($item, $this-&gt;data['items']);
            }
            if (!empty($this-&gt;data['ordered_items'])) {
                foreach ($this-&gt;data['ordered_items'] as $item) {
                    $item-&gt;__destruct();
                }
                unset($item, $this-&gt;data['ordered_items']);
            }
        }
    }

    /**
     * Force the given data/URL to be treated as a feed
     *
     * This tells SimplePie to ignore the content-type provided by the server.
     * Be careful when using this option, as it will also disable autodiscovery.
     *
     * @since 1.1
     * @param bool $enable Force the given data/URL to be treated as a feed
     */
    public function force_feed($enable = false)
    {
        $this-&gt;force_feed = (bool) $enable;
    }

    /**
     * Set the URL of the feed you want to parse
     *
     * This allows you to enter the URL of the feed you want to parse, or the
     * website you want to try to use auto-discovery on. This takes priority
     * over any set raw data.
     *
     * You can set multiple feeds to mash together by passing an array instead
     * of a string for the $url. Remember that with each additional feed comes
     * additional processing and resources.
     *
     * @since 1.0 Preview Release
     * @see set_raw_data()
     * @param string|array $url This is the URL (or array of URLs) that you want to parse.
     */
    public function set_feed_url($url)
    {
        $this-&gt;multifeed_url = [];
        if (is_array($url)) {
            foreach ($url as $value) {
                $this-&gt;multifeed_url[] = $this-&gt;registry-&gt;call(Misc::class, 'fix_protocol', [$value, 1]);
            }
        } else {
            $this-&gt;feed_url = $this-&gt;registry-&gt;call(Misc::class, 'fix_protocol', [$url, 1]);
            $this-&gt;permanent_url = $this-&gt;feed_url;
        }
    }

    /**
     * Set an instance of {@see \SimplePie\File} to use as a feed
     *
     * @param \SimplePie\File &amp;$file
     * @return bool True on success, false on failure
     */
    public function set_file(&amp;$file)
    {
        if ($file instanceof \SimplePie\File) {
            $this-&gt;feed_url = $file-&gt;url;
            $this-&gt;permanent_url = $this-&gt;feed_url;
            $this-&gt;file = &amp;$file;
            return true;
        }
        return false;
    }

    /**
     * Set the raw XML data to parse
     *
     * Allows you to use a string of RSS/Atom data instead of a remote feed.
     *
     * If you have a feed available as a string in PHP, you can tell SimplePie
     * to parse that data string instead of a remote feed. Any set feed URL
     * takes precedence.
     *
     * @since 1.0 Beta 3
     * @param string $data RSS or Atom data as a string.
     * @see set_feed_url()
     */
    public function set_raw_data($data)
    {
        $this-&gt;raw_data = $data;
    }

    /**
     * Set the default timeout for fetching remote feeds
     *
     * This allows you to change the maximum time the feed's server to respond
     * and send the feed back.
     *
     * @since 1.0 Beta 3
     * @param int $timeout The maximum number of seconds to spend waiting to retrieve a feed.
     */
    public function set_timeout($timeout = 10)
    {
        $this-&gt;timeout = (int) $timeout;
    }

    /**
     * Set custom curl options
     *
     * This allows you to change default curl options
     *
     * @since 1.0 Beta 3
     * @param array $curl_options Curl options to add to default settings
     */
    public function set_curl_options(array $curl_options = [])
    {
        $this-&gt;curl_options = $curl_options;
    }

    /**
     * Force SimplePie to use fsockopen() instead of cURL
     *
     * @since 1.0 Beta 3
     * @param bool $enable Force fsockopen() to be used
     */
    public function force_fsockopen($enable = false)
    {
        $this-&gt;force_fsockopen = (bool) $enable;
    }

    /**
     * Enable/disable caching in SimplePie.
     *
     * This option allows you to disable caching all-together in SimplePie.
     * However, disabling the cache can lead to longer load times.
     *
     * @since 1.0 Preview Release
     * @param bool $enable Enable caching
     */
    public function enable_cache($enable = true)
    {
        $this-&gt;enable_cache = (bool) $enable;
    }

    /**
     * Set a PSR-16 implementation as cache
     *
     * @param CacheInterface $psr16cache The PSR-16 cache implementation
     *
     * @return void
     */
    public function set_cache(CacheInterface $cache)
    {
        $this-&gt;cache = new Psr16($cache);
    }

    /**
     * SimplePie to continue to fall back to expired cache, if enabled, when
     * feed is unavailable.
     *
     * This tells SimplePie to ignore any file errors and fall back to cache
     * instead. This only works if caching is enabled and cached content
     * still exists.
     *
     * @deprecated since SimplePie 1.8.0, expired cache will not be used anymore.
     *
     * @param bool $enable Force use of cache on fail.
     */
    public function force_cache_fallback($enable = false)
    {
        // @trigger_error(sprintf('SimplePie\SimplePie::force_cache_fallback() is deprecated since SimplePie 1.8.0, expired cache will not be used anymore.'), \E_USER_DEPRECATED);
        $this-&gt;force_cache_fallback = (bool) $enable;
    }

    /**
     * Set the length of time (in seconds) that the contents of a feed will be
     * cached
     *
     * @param int $seconds The feed content cache duration
     */
    public function set_cache_duration($seconds = 3600)
    {
        $this-&gt;cache_duration = (int) $seconds;
    }

    /**
     * Set the length of time (in seconds) that the autodiscovered feed URL will
     * be cached
     *
     * @param int $seconds The autodiscovered feed URL cache duration.
     */
    public function set_autodiscovery_cache_duration($seconds = 604800)
    {
        $this-&gt;autodiscovery_cache_duration = (int) $seconds;
    }

    /**
     * Set the file system location where the cached files should be stored
     *
     * @deprecated since SimplePie 1.8.0, use \SimplePie\SimplePie::set_cache() instead.
     *
     * @param string $location The file system location.
     */
    public function set_cache_location($location = './cache')
    {
        // @trigger_error(sprintf('SimplePie\SimplePie::set_cache_location() is deprecated since SimplePie 1.8.0, please use &quot;SimplePie\SimplePie::set_cache()&quot; instead.'), \E_USER_DEPRECATED);
        $this-&gt;cache_location = (string) $location;
    }

    /**
     * Return the filename (i.e. hash, without path and without extension) of the file to cache a given URL.
     *
     * @param string $url The URL of the feed to be cached.
     * @return string A filename (i.e. hash, without path and without extension).
     */
    public function get_cache_filename($url)
    {
        // Append custom parameters to the URL to avoid cache pollution in case of multiple calls with different parameters.
        $url .= $this-&gt;force_feed ? '#force_feed' : '';
        $options = [];
        if ($this-&gt;timeout != 10) {
            $options[CURLOPT_TIMEOUT] = $this-&gt;timeout;
        }
        if ($this-&gt;useragent !== \SimplePie\Misc::get_default_useragent()) {
            $options[CURLOPT_USERAGENT] = $this-&gt;useragent;
        }
        if (!empty($this-&gt;curl_options)) {
            foreach ($this-&gt;curl_options as $k =&gt; $v) {
                $options[$k] = $v;
            }
        }
        if (!empty($options)) {
            ksort($options);
            $url .= '#' . urlencode(var_export($options, true));
        }

        return $this-&gt;cache_namefilter-&gt;filter($url);
    }

    /**
     * Set whether feed items should be sorted into reverse chronological order
     *
     * @param bool $enable Sort as reverse chronological order.
     */
    public function enable_order_by_date($enable = true)
    {
        $this-&gt;order_by_date = (bool) $enable;
    }

    /**
     * Set the character encoding used to parse the feed
     *
     * This overrides the encoding reported by the feed, however it will fall
     * back to the normal encoding detection if the override fails
     *
     * @param string $encoding Character encoding
     */
    public function set_input_encoding($encoding = false)
    {
        if ($encoding) {
            $this-&gt;input_encoding = (string) $encoding;
        } else {
            $this-&gt;input_encoding = false;
        }
    }

    /**
     * Set how much feed autodiscovery to do
     *
     * @see \SimplePie\SimplePie::LOCATOR_NONE
     * @see \SimplePie\SimplePie::LOCATOR_AUTODISCOVERY
     * @see \SimplePie\SimplePie::LOCATOR_LOCAL_EXTENSION
     * @see \SimplePie\SimplePie::LOCATOR_LOCAL_BODY
     * @see \SimplePie\SimplePie::LOCATOR_REMOTE_EXTENSION
     * @see \SimplePie\SimplePie::LOCATOR_REMOTE_BODY
     * @see \SimplePie\SimplePie::LOCATOR_ALL
     * @param int $level Feed Autodiscovery Level (level can be a combination of the above constants, see bitwise OR operator)
     */
    public function set_autodiscovery_level($level = self::LOCATOR_ALL)
    {
        $this-&gt;autodiscovery = (int) $level;
    }

    /**
     * Get the class registry
     *
     * Use this to override SimplePie's default classes
     * @see \SimplePie\Registry
     *
     * @return Registry
     */
    public function &amp;get_registry()
    {
        return $this-&gt;registry;
    }

    /**
     * Set which class SimplePie uses for caching
     *
     * @deprecated since SimplePie 1.3, use {@see set_cache()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_cache_class($class = Cache::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::set_cache()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Cache::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for auto-discovery
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_locator_class($class = Locator::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Locator::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for XML parsing
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_parser_class($class = Parser::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Parser::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for remote file fetching
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_file_class($class = File::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(File::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for data sanitization
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_sanitize_class($class = Sanitize::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Sanitize::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for handling feed items
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_item_class($class = Item::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Item::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for handling author data
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_author_class($class = Author::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Author::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for handling category data
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_category_class($class = Category::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Category::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for feed enclosures
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_enclosure_class($class = Enclosure::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Enclosure::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for `&lt;media:text&gt;` captions
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_caption_class($class = Caption::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Caption::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for `&lt;media:copyright&gt;`
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_copyright_class($class = Copyright::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Copyright::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for `&lt;media:credit&gt;`
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_credit_class($class = Credit::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Credit::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for `&lt;media:rating&gt;`
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_rating_class($class = Rating::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Rating::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for `&lt;media:restriction&gt;`
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_restriction_class($class = Restriction::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Restriction::class, $class, true);
    }

    /**
     * Set which class SimplePie uses for content-type sniffing
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_content_type_sniffer_class($class = Sniffer::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Sniffer::class, $class, true);
    }

    /**
     * Set which class SimplePie uses item sources
     *
     * @deprecated since SimplePie 1.3, use {@see get_registry()} instead
     *
     * @param string $class Name of custom class
     *
     * @return boolean True on success, false otherwise
     */
    public function set_source_class($class = Source::class)
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.3, please use &quot;SimplePie\SimplePie::get_registry()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        return $this-&gt;registry-&gt;register(Source::class, $class, true);
    }

    /**
     * Set the user agent string
     *
     * @param string $ua New user agent string.
     */
    public function set_useragent($ua = null)
    {
        if ($ua === null) {
            $ua = \SimplePie\Misc::get_default_useragent();
        }

        $this-&gt;useragent = (string) $ua;
    }

    /**
     * Set a namefilter to modify the cache filename with
     *
     * @param NameFilter $filter
     *
     * @return void
     */
    public function set_cache_namefilter(NameFilter $filter): void
    {
        $this-&gt;cache_namefilter = $filter;
    }

    /**
     * Set callback function to create cache filename with
     *
     * @deprecated since SimplePie 1.8.0, use {@see set_cache_namefilter()} instead
     *
     * @param mixed $function Callback function
     */
    public function set_cache_name_function($function = 'md5')
    {
        // trigger_error(sprintf('&quot;%s()&quot; is deprecated since SimplePie 1.8.0, please use &quot;SimplePie\SimplePie::set_cache_namefilter()&quot; instead.', __METHOD__), \E_USER_DEPRECATED);

        if (is_callable($function)) {
            $this-&gt;cache_name_function = $function;

            $this-&gt;set_cache_namefilter(new CallableNameFilter($this-&gt;cache_name_function));
        }
    }

    /**
     * Set options to make SP as fast as possible
     *
     * Forgoes a substantial amount of data sanitization in favor of speed. This
     * turns SimplePie into a dumb parser of feeds.
     *
     * @param bool $set Whether to set them or not
     */
    public function set_stupidly_fast($set = false)
    {
        if ($set) {
            $this-&gt;enable_order_by_date(false);
            $this-&gt;remove_div(false);
            $this-&gt;strip_comments(false);
            $this-&gt;strip_htmltags(false);
            $this-&gt;strip_attributes(false);
            $this-&gt;add_attributes(false);
            $this-&gt;set_image_handler(false);
            $this-&gt;set_https_domains([]);
        }
    }

    /**
     * Set maximum number of feeds to check with autodiscovery
     *
     * @param int $max Maximum number of feeds to check
     */
    public function set_max_checked_feeds($max = 10)
    {
        $this-&gt;max_checked_feeds = (int) $max;
    }

    public function remove_div($enable = true)
    {
        $this-&gt;sanitize-&gt;remove_div($enable);
    }

    public function strip_htmltags($tags = '', $encode = null)
    {
        if ($tags === '') {
            $tags = $this-&gt;strip_htmltags;
        }
        $this-&gt;sanitize-&gt;strip_htmltags($tags);
        if ($encode !== null) {
            $this-&gt;sanitize-&gt;encode_instead_of_strip($tags);
        }
    }

    public function encode_instead_of_strip($enable = true)
    {
        $this-&gt;sanitize-&gt;encode_instead_of_strip($enable);
    }

    public function rename_attributes($attribs = '')
    {
        if ($attribs === '') {
            $attribs = $this-&gt;rename_attributes;
        }
        $this-&gt;sanitize-&gt;rename_attributes($attribs);
    }

    public function strip_attributes($attribs = '')
    {
        if ($attribs === '') {
            $attribs = $this-&gt;strip_attributes;
        }
        $this-&gt;sanitize-&gt;strip_attributes($attribs);
    }

    public function add_attributes($attribs = '')
    {
        if ($attribs === '') {
            $attribs = $this-&gt;add_attributes;
        }
        $this-&gt;sanitize-&gt;add_attributes($attribs);
    }

    /**
     * Set the output encoding
     *
     * Allows you to override SimplePie's output to match that of your webpage.
     * This is useful for times when your webpages are not being served as
     * UTF-8. This setting will be obeyed by {@see handle_content_type()}, and
     * is similar to {@see set_input_encoding()}.
     *
     * It should be noted, however, that not all character encodings can support
     * all characters. If your page is being served as ISO-8859-1 and you try
     * to display a Japanese feed, you'll likely see garbled characters.
     * Because of this, it is highly recommended to ensure that your webpages
     * are served as UTF-8.
     *
     * The number of supported character encodings depends on whether your web
     * host supports {@link http://php.net/mbstring mbstring},
     * {@link http://php.net/iconv iconv}, or both. See
     * {@link http://simplepie.org/wiki/faq/Supported_Character_Encodings} for
     * more information.
     *
     * @param string $encoding
     */
    public function set_output_encoding($encoding = 'UTF-8')
    {
        $this-&gt;sanitize-&gt;set_output_encoding($encoding);
    }

    public function strip_comments($strip = false)
    {
        $this-&gt;sanitize-&gt;strip_comments($strip);
    }

    /**
     * Set element/attribute key/value pairs of HTML attributes
     * containing URLs that need to be resolved relative to the feed
     *
     * Defaults to |a|@href, |area|@href, |blockquote|@cite, |del|@cite,
     * |form|@action, |img|@longdesc, |img|@src, |input|@src, |ins|@cite,
     * |q|@cite
     *
     * @since 1.0
     * @param array|null $element_attribute Element/attribute key/value pairs, null for default
     */
    public function set_url_replacements($element_attribute = null)
    {
        $this-&gt;sanitize-&gt;set_url_replacements($element_attribute);
    }

    /**
     * Set the list of domains for which to force HTTPS.
     * @see \SimplePie\Sanitize::set_https_domains()
     * @param array List of HTTPS domains. Example array('biz', 'example.com', 'example.org', 'www.example.net').
     */
    public function set_https_domains($domains = [])
    {
        if (is_array($domains)) {
            $this-&gt;sanitize-&gt;set_https_domains($domains);
        }
    }

    /**
     * Set the handler to enable the display of cached images.
     *
     * @param string $page Web-accessible path to the handler_image.php file.
     * @param string $qs The query string that the value should be passed to.
     */
    public function set_image_handler($page = false, $qs = 'i')
    {
        if ($page !== false) {
            $this-&gt;sanitize-&gt;set_image_handler($page . '?' . $qs . '=');
        } else {
            $this-&gt;image_handler = '';
        }
    }

    /**
     * Set the limit for items returned per-feed with multifeeds
     *
     * @param integer $limit The maximum number of items to return.
     */
    public function set_item_limit($limit = 0)
    {
        $this-&gt;item_limit = (int) $limit;
    }

    /**
     * Enable throwing exceptions
     *
     * @param boolean $enable Should we throw exceptions, or use the old-style error property?
     */
    public function enable_exceptions($enable = true)
    {
        $this-&gt;enable_exceptions = $enable;
    }

    /**
     * Initialize the feed object
     *
     * This is what makes everything happen. Period. This is where all of the
     * configuration options get processed, feeds are fetched, cached, and
     * parsed, and all of that other good stuff.
     *
     * @return boolean True if successful, false otherwise
     */
    public function init()
    {
        // Check absolute bare minimum requirements.
        if (!extension_loaded('xml') || !extension_loaded('pcre')) {
            $this-&gt;error = 'XML or PCRE extensions not loaded!';
            return false;
        }
        // Then check the xml extension is sane (i.e., libxml 2.7.x issue on PHP &lt; 5.2.9 and libxml 2.7.0 to 2.7.2 on any version) if we don't have xmlreader.
        elseif (!extension_loaded('xmlreader')) {
            static $xml_is_sane = null;
            if ($xml_is_sane === null) {
                $parser_check = xml_parser_create();
                xml_parse_into_struct($parser_check, '&lt;foo&gt;&amp;amp;&lt;/foo&gt;', $values);
                xml_parser_free($parser_check);
                $xml_is_sane = isset($values[0]['value']);
            }
            if (!$xml_is_sane) {
                return false;
            }
        }

        // The default sanitize class gets set in the constructor, check if it has
        // changed.
        if ($this-&gt;registry-&gt;get_class(Sanitize::class) !== 'SimplePie\Sanitize') {
            $this-&gt;sanitize = $this-&gt;registry-&gt;create(Sanitize::class);
        }
        if (method_exists($this-&gt;sanitize, 'set_registry')) {
            $this-&gt;sanitize-&gt;set_registry($this-&gt;registry);
        }

        // Pass whatever was set with config options over to the sanitizer.
        // Pass the classes in for legacy support; new classes should use the registry instead
        $this-&gt;sanitize-&gt;pass_cache_data(
            $this-&gt;enable_cache,
            $this-&gt;cache_location,
            $this-&gt;cache_namefilter,
            $this-&gt;registry-&gt;get_class(Cache::class),
            $this-&gt;cache
        );
        $this-&gt;sanitize-&gt;pass_file_data($this-&gt;registry-&gt;get_class(File::class), $this-&gt;timeout, $this-&gt;useragent, $this-&gt;force_fsockopen, $this-&gt;curl_options);

        if (!empty($this-&gt;multifeed_url)) {
            $i = 0;
            $success = 0;
            $this-&gt;multifeed_objects = [];
            $this-&gt;error = [];
            foreach ($this-&gt;multifeed_url as $url) {
                $this-&gt;multifeed_objects[$i] = clone $this;
                $this-&gt;multifeed_objects[$i]-&gt;set_feed_url($url);
                $single_success = $this-&gt;multifeed_objects[$i]-&gt;init();
                $success |= $single_success;
                if (!$single_success) {
                    $this-&gt;error[$i] = $this-&gt;multifeed_objects[$i]-&gt;error();
                }
                $i++;
            }
            return (bool) $success;
        } elseif ($this-&gt;feed_url === null &amp;&amp; $this-&gt;raw_data === null) {
            return false;
        }

        $this-&gt;error = null;
        $this-&gt;data = [];
        $this-&gt;check_modified = false;
        $this-&gt;multifeed_objects = [];
        $cache = false;

        if ($this-&gt;feed_url !== null) {
            $parsed_feed_url = $this-&gt;registry-&gt;call(Misc::class, 'parse_url', [$this-&gt;feed_url]);

            // Decide whether to enable caching
            if ($this-&gt;enable_cache &amp;&amp; $parsed_feed_url['scheme'] !== '') {
                $cache = $this-&gt;get_cache($this-&gt;feed_url);
            }

            // Fetch the data via \SimplePie\File into $this-&gt;raw_data
            if (($fetched = $this-&gt;fetch_data($cache)) === true) {
                return true;
            } elseif ($fetched === false) {
                return false;
            }

            [$headers, $sniffed] = $fetched;
        }

        // Empty response check
        if (empty($this-&gt;raw_data)) {
            $this-&gt;error = &quot;A feed could not be found at `$this-&gt;feed_url`. Empty body.&quot;;
            $this-&gt;registry-&gt;call(Misc::class, 'error', [$this-&gt;error, E_USER_NOTICE, __FILE__, __LINE__]);
            return false;
        }

        // Set up array of possible encodings
        $encodings = [];

        // First check to see if input has been overridden.
        if ($this-&gt;input_encoding !== false) {
            $encodings[] = strtoupper($this-&gt;input_encoding);
        }

        $application_types = ['application/xml', 'application/xml-dtd', 'application/xml-external-parsed-entity'];
        $text_types = ['text/xml', 'text/xml-external-parsed-entity'];

        // RFC 3023 (only applies to sniffed content)
        if (isset($sniffed)) {
            if (in_array($sniffed, $application_types) || substr($sniffed, 0, 12) === 'application/' &amp;&amp; substr($sniffed, -4) === '+xml') {
                if (isset($headers['content-type']) &amp;&amp; preg_match('/;\x20?charset=([^;]*)/i', $headers['content-type'], $charset)) {
                    $encodings[] = strtoupper($charset[1]);
                }
                $encodings = array_merge($encodings, $this-&gt;registry-&gt;call(Misc::class, 'xml_encoding', [$this-&gt;raw_data, &amp;$this-&gt;registry]));
                $encodings[] = 'UTF-8';
            } elseif (in_array($sniffed, $text_types) || substr($sniffed, 0, 5) === 'text/' &amp;&amp; substr($sniffed, -4) === '+xml') {
                if (isset($headers['content-type']) &amp;&amp; preg_match('/;\x20?charset=([^;]*)/i', $headers['content-type'], $charset)) {
                    $encodings[] = strtoupper($charset[1]);
                }
                $encodings[] = 'US-ASCII';
            }
            // Text MIME-type default
            elseif (substr($sniffed, 0, 5) === 'text/') {
                $encodings[] = 'UTF-8';
            }
        }

        // Fallback to XML 1.0 Appendix F.1/UTF-8/ISO-8859-1
        $encodings = array_merge($encodings, $this-&gt;registry-&gt;call(Misc::class, 'xml_encoding', [$this-&gt;raw_data, &amp;$this-&gt;registry]));
        $encodings[] = 'UTF-8';
        $encodings[] = 'ISO-8859-1';

        // There's no point in trying an encoding twice
        $encodings = array_unique($encodings);

        // Loop through each possible encoding, till we return something, or run out of possibilities
        foreach ($encodings as $encoding) {
            // Change the encoding to UTF-8 (as we always use UTF-8 internally)
            if ($utf8_data = $this-&gt;registry-&gt;call(Misc::class, 'change_encoding', [$this-&gt;raw_data, $encoding, 'UTF-8'])) {
                // Create new parser
                $parser = $this-&gt;registry-&gt;create(Parser::class);

                // If it's parsed fine
                if ($parser-&gt;parse($utf8_data, 'UTF-8', $this-&gt;permanent_url)) {
                    $this-&gt;data = $parser-&gt;get_data();
                    if (!($this-&gt;get_type() &amp; ~self::TYPE_NONE)) {
                        $this-&gt;error = &quot;A feed could not be found at `$this-&gt;feed_url`. This does not appear to be a valid RSS or Atom feed.&quot;;
                        $this-&gt;registry-&gt;call(Misc::class, 'error', [$this-&gt;error, E_USER_NOTICE, __FILE__, __LINE__]);
                        return false;
                    }

                    if (isset($headers)) {
                        $this-&gt;data['headers'] = $headers;
                    }
                    $this-&gt;data['build'] = \SimplePie\Misc::get_build();

                    // Cache the file if caching is enabled
                    $this-&gt;data['cache_expiration_time'] = $this-&gt;cache_duration + time();
                    if ($cache &amp;&amp; !$cache-&gt;set_data($this-&gt;get_cache_filename($this-&gt;feed_url), $this-&gt;data, $this-&gt;cache_duration)) {
                        trigger_error(&quot;$this-&gt;cache_location is not writable. Make sure you've set the correct relative or absolute path, and that the location is server-writable.&quot;, E_USER_WARNING);
                    }
                    return true;
                }
            }
        }

        if (isset($parser)) {
            // We have an error, just set \SimplePie\Misc::error to it and quit
            $this-&gt;error = $this-&gt;feed_url;
            $this-&gt;error .= sprintf(' is invalid XML, likely due to invalid characters. XML error: %s at line %d, column %d', $parser-&gt;get_error_string(), $parser-&gt;get_current_line(), $parser-&gt;get_current_column());
        } else {
            $this-&gt;error = 'The data could not be converted to UTF-8.';
            if (!extension_loaded('mbstring') &amp;&amp; !extension_loaded('iconv') &amp;&amp; !class_exists('\UConverter')) {
                $this-&gt;error .= ' You MUST have either the iconv, mbstring or intl (PHP 5.5+) extension installed and enabled.';
            } else {
                $missingExtensions = [];
                if (!extension_loaded('iconv')) {
                    $missingExtensions[] = 'iconv';
                }
                if (!extension_loaded('mbstring')) {
                    $missingExtensions[] = 'mbstring';
                }
                if (!class_exists('\UConverter')) {
                    $missingExtensions[] = 'intl (PHP 5.5+)';
                }
                $this-&gt;error .= ' Try installing/enabling the ' . implode(' or ', $missingExtensions) . ' extension.';
            }
        }

        $this-&gt;registry-&gt;call(Misc::class, 'error', [$this-&gt;error, E_USER_NOTICE, __FILE__, __LINE__]);

        return false;
    }

    /**
     * Fetch the data via \SimplePie\File
     *
     * If the data is already cached, attempt to fetch it from there instead
     * @param Base|DataCache|false $cache Cache handler, or false to not load from the cache
     * @return array|true Returns true if the data was loaded from the cache, or an array of HTTP headers and sniffed type
     */
    protected function fetch_data(&amp;$cache)
    {
        if (is_object($cache) &amp;&amp; $cache instanceof Base) {
            // @trigger_error(sprintf('Providing $cache as &quot;\SimplePie\Cache\Base&quot; in %s() is deprecated since SimplePie 1.8.0, please provide &quot;\SimplePie\Cache\DataCache&quot; implementation instead.', __METHOD__), \E_USER_DEPRECATED);
            $cache = new BaseDataCache($cache);
        }

        if ($cache !== false &amp;&amp; !$cache instanceof DataCache) {
            throw new InvalidArgumentException(sprintf(
                '%s(): Argument #1 ($cache) must be of type %s|false',
                __METHOD__,
                DataCache::class
            ), 1);
        }

        $cacheKey = $this-&gt;get_cache_filename($this-&gt;feed_url);

        // If it's enabled, use the cache
        if ($cache) {
            // Load the Cache
            $this-&gt;data = $cache-&gt;get_data($cacheKey, []);

            if (!empty($this-&gt;data)) {
                // If the cache is for an outdated build of SimplePie
                if (!isset($this-&gt;data['build']) || $this-&gt;data['build'] !== \SimplePie\Misc::get_build()) {
                    $cache-&gt;delete_data($cacheKey);
                    $this-&gt;data = [];
                }
                // If we've hit a collision just rerun it with caching disabled
                elseif (isset($this-&gt;data['url']) &amp;&amp; $this-&gt;data['url'] !== $this-&gt;feed_url) {
                    $cache = false;
                    $this-&gt;data = [];
                }
                // If we've got a non feed_url stored (if the page isn't actually a feed, or is a redirect) use that URL.
                elseif (isset($this-&gt;data['feed_url'])) {
                    // Do not need to do feed autodiscovery yet.
                    if ($this-&gt;data['feed_url'] !== $this-&gt;data['url']) {
                        $this-&gt;set_feed_url($this-&gt;data['feed_url']);
                        $this-&gt;data['url'] = $this-&gt;data['feed_url'];

                        $cache-&gt;set_data($this-&gt;get_cache_filename($this-&gt;feed_url), $this-&gt;data, $this-&gt;autodiscovery_cache_duration);

                        return $this-&gt;init();
                    }

                    $cache-&gt;delete_data($this-&gt;get_cache_filename($this-&gt;feed_url));
                    $this-&gt;data = [];
                }
                // Check if the cache has been updated
                elseif (isset($this-&gt;data['cache_expiration_time']) &amp;&amp; $this-&gt;data['cache_expiration_time'] &gt; time()) {
                    // Want to know if we tried to send last-modified and/or etag headers
                    // when requesting this file. (Note that it's up to the file to
                    // support this, but we don't always send the headers either.)
                    $this-&gt;check_modified = true;
                    if (isset($this-&gt;data['headers']['last-modified']) || isset($this-&gt;data['headers']['etag'])) {
                        $headers = [
                            'Accept' =&gt; 'application/atom+xml, application/rss+xml, application/rdf+xml;q=0.9, application/xml;q=0.8, text/xml;q=0.8, text/html;q=0.7, unknown/unknown;q=0.1, application/unknown;q=0.1, */*;q=0.1',
                        ];
                        if (isset($this-&gt;data['headers']['last-modified'])) {
                            $headers['if-modified-since'] = $this-&gt;data['headers']['last-modified'];
                        }
                        if (isset($this-&gt;data['headers']['etag'])) {
                            $headers['if-none-match'] = $this-&gt;data['headers']['etag'];
                        }

                        $file = $this-&gt;registry-&gt;create(File::class, [$this-&gt;feed_url, $this-&gt;timeout / 10, 5, $headers, $this-&gt;useragent, $this-&gt;force_fsockopen, $this-&gt;curl_options]);
                        $this-&gt;status_code = $file-&gt;status_code;

                        if ($file-&gt;success) {
                            if ($file-&gt;status_code === 304) {
                                // Set raw_data to false here too, to signify that the cache
                                // is still valid.
                                $this-&gt;raw_data = false;
                                $cache-&gt;set_data($cacheKey, $this-&gt;data, $this-&gt;cache_duration);
                                return true;
                            }
                        } else {
                            $this-&gt;check_modified = false;
                            if ($this-&gt;force_cache_fallback) {
                                $cache-&gt;set_data($cacheKey, $this-&gt;data, $this-&gt;cache_duration);
                                return true;
                            }

                            unset($file);
                        }
                    }
                }
                // If the cache is still valid, just return true
                else {
                    $this-&gt;raw_data = false;
                    return true;
                }
            }
            // If the cache is empty
            else {
                $this-&gt;data = [];
            }
        }

        // If we don't already have the file (it'll only exist if we've opened it to check if the cache has been modified), open it.
        if (!isset($file)) {
            if ($this-&gt;file instanceof \SimplePie\File &amp;&amp; $this-&gt;file-&gt;url === $this-&gt;feed_url) {
                $file = &amp;$this-&gt;file;
            } else {
                $headers = [
                    'Accept' =&gt; 'application/atom+xml, application/rss+xml, application/rdf+xml;q=0.9, application/xml;q=0.8, text/xml;q=0.8, text/html;q=0.7, unknown/unknown;q=0.1, application/unknown;q=0.1, */*;q=0.1',
                ];
                $file = $this-&gt;registry-&gt;create(File::class, [$this-&gt;feed_url, $this-&gt;timeout, 5, $headers, $this-&gt;useragent, $this-&gt;force_fsockopen, $this-&gt;curl_options]);
            }
        }
        $this-&gt;status_code = $file-&gt;status_code;

        // If the file connection has an error, set SimplePie::error to that and quit
        if (!$file-&gt;success &amp;&amp; !($file-&gt;method &amp; self::FILE_SOURCE_REMOTE === 0 || ($file-&gt;status_code === 200 || $file-&gt;status_code &gt; 206 &amp;&amp; $file-&gt;status_code &lt; 300))) {
            $this-&gt;error = $file-&gt;error;
            return !empty($this-&gt;data);
        }

        if (!$this-&gt;force_feed) {
            // Check if the supplied URL is a feed, if it isn't, look for it.
            $locate = $this-&gt;registry-&gt;create(Locator::class, [&amp;$file, $this-&gt;timeout, $this-&gt;useragent, $this-&gt;max_checked_feeds, $this-&gt;force_fsockopen, $this-&gt;curl_options]);

            if (!$locate-&gt;is_feed($file)) {
                $copyStatusCode = $file-&gt;status_code;
                $copyContentType = $file-&gt;headers['content-type'];
                try {
                    $microformats = false;
                    if (class_exists('DOMXpath') &amp;&amp; function_exists('Mf2\parse')) {
                        $doc = new \DOMDocument();
                        @$doc-&gt;loadHTML($file-&gt;body);
                        $xpath = new \DOMXpath($doc);
                        // Check for both h-feed and h-entry, as both a feed with no entries
                        // and a list of entries without an h-feed wrapper are both valid.
                        $query = '//*[contains(concat(&quot; &quot;, @class, &quot; &quot;), &quot; h-feed &quot;) or '.
                            'contains(concat(&quot; &quot;, @class, &quot; &quot;), &quot; h-entry &quot;)]';
                        $result = $xpath-&gt;query($query);
                        $microformats = $result-&gt;length !== 0;
                    }
                    // Now also do feed discovery, but if microformats were found don't
                    // overwrite the current value of file.
                    $discovered = $locate-&gt;find(
                        $this-&gt;autodiscovery,
                        $this-&gt;all_discovered_feeds
                    );
                    if ($microformats) {
                        if ($hub = $locate-&gt;get_rel_link('hub')) {
                            $self = $locate-&gt;get_rel_link('self');
                            $this-&gt;store_links($file, $hub, $self);
                        }
                        // Push the current file onto all_discovered feeds so the user can
                        // be shown this as one of the options.
                        if (isset($this-&gt;all_discovered_feeds)) {
                            $this-&gt;all_discovered_feeds[] = $file;
                        }
                    } else {
                        if ($discovered) {
                            $file = $discovered;
                        } else {
                            // We need to unset this so that if SimplePie::set_file() has
                            // been called that object is untouched
                            unset($file);
                            $this-&gt;error = &quot;A feed could not be found at `$this-&gt;feed_url`; the status code is `$copyStatusCode` and content-type is `$copyContentType`&quot;;
                            $this-&gt;registry-&gt;call(Misc::class, 'error', [$this-&gt;error, E_USER_NOTICE, __FILE__, __LINE__]);
                            return false;
                        }
                    }
                } catch (\SimplePie\Exception $e) {
                    // We need to unset this so that if SimplePie::set_file() has been called that object is untouched
                    unset($file);
                    // This is usually because DOMDocument doesn't exist
                    $this-&gt;error = $e-&gt;getMessage();
                    $this-&gt;registry-&gt;call(Misc::class, 'error', [$this-&gt;error, E_USER_NOTICE, $e-&gt;getFile(), $e-&gt;getLine()]);
                    return false;
                }

                if ($cache) {
                    $this-&gt;data = [
                        'url' =&gt; $this-&gt;feed_url,
                        'feed_url' =&gt; $file-&gt;url,
                        'build' =&gt; \SimplePie\Misc::get_build(),
                        'cache_expiration_time' =&gt; $this-&gt;cache_duration + time(),
                    ];

                    if (!$cache-&gt;set_data($cacheKey, $this-&gt;data, $this-&gt;cache_duration)) {
                        trigger_error(&quot;$this-&gt;cache_location is not writable. Make sure you've set the correct relative or absolute path, and that the location is server-writable.&quot;, E_USER_WARNING);
                    }
                }
            }
            $this-&gt;feed_url = $file-&gt;url;
            $locate = null;
        }

        $this-&gt;raw_data = $file-&gt;body;
        $this-&gt;permanent_url = $file-&gt;permanent_url;
        $headers = $file-&gt;headers;
        $sniffer = $this-&gt;registry-&gt;create(Sniffer::class, [&amp;$file]);
        $sniffed = $sniffer-&gt;get_type();

        return [$headers, $sniffed];
    }

    /**
     * Get the error message for the occurred error
     *
     * @return string|array Error message, or array of messages for multifeeds
     */
    public function error()
    {
        return $this-&gt;error;
    }

    /**
     * Get the last HTTP status code
     *
     * @return int Status code
     */
    public function status_code()
    {
        return $this-&gt;status_code;
    }

    /**
     * Get the raw XML
     *
     * This is the same as the old `$feed-&gt;enable_xml_dump(true)`, but returns
     * the data instead of printing it.
     *
     * @return string|boolean Raw XML data, false if the cache is used
     */
    public function get_raw_data()
    {
        return $this-&gt;raw_data;
    }

    /**
     * Get the character encoding used for output
     *
     * @since Preview Release
     * @return string
     */
    public function get_encoding()
    {
        return $this-&gt;sanitize-&gt;output_encoding;
    }

    /**
     * Send the content-type header with correct encoding
     *
     * This method ensures that the SimplePie-enabled page is being served with
     * the correct {@link http://www.iana.org/assignments/media-types/ mime-type}
     * and character encoding HTTP headers (character encoding determined by the
     * {@see set_output_encoding} config option).
     *
     * This won't work properly if any content or whitespace has already been
     * sent to the browser, because it relies on PHP's
     * {@link http://php.net/header header()} function, and these are the
     * circumstances under which the function works.
     *
     * Because it's setting these settings for the entire page (as is the nature
     * of HTTP headers), this should only be used once per page (again, at the
     * top).
     *
     * @param string $mime MIME type to serve the page as
     */
    public function handle_content_type($mime = 'text/html')
    {
        if (!headers_sent()) {
            $header = &quot;Content-type: $mime;&quot;;
            if ($this-&gt;get_encoding()) {
                $header .= ' charset=' . $this-&gt;get_encoding();
            } else {
                $header .= ' charset=UTF-8';
            }
            header($header);
        }
    }

    /**
     * Get the type of the feed
     *
     * This returns a \SimplePie\SimplePie::TYPE_* constant, which can be tested against
     * using {@link http://php.net/language.operators.bitwise bitwise operators}
     *
     * @since 0.8 (usage changed to using constants in 1.0)
     * @see \SimplePie\SimplePie::TYPE_NONE Unknown.
     * @see \SimplePie\SimplePie::TYPE_RSS_090 RSS 0.90.
     * @see \SimplePie\SimplePie::TYPE_RSS_091_NETSCAPE RSS 0.91 (Netscape).
     * @see \SimplePie\SimplePie::TYPE_RSS_091_USERLAND RSS 0.91 (Userland).
     * @see \SimplePie\SimplePie::TYPE_RSS_091 RSS 0.91.
     * @see \SimplePie\SimplePie::TYPE_RSS_092 RSS 0.92.
     * @see \SimplePie\SimplePie::TYPE_RSS_093 RSS 0.93.
     * @see \SimplePie\SimplePie::TYPE_RSS_094 RSS 0.94.
     * @see \SimplePie\SimplePie::TYPE_RSS_10 RSS 1.0.
     * @see \SimplePie\SimplePie::TYPE_RSS_20 RSS 2.0.x.
     * @see \SimplePie\SimplePie::TYPE_RSS_RDF RDF-based RSS.
     * @see \SimplePie\SimplePie::TYPE_RSS_SYNDICATION Non-RDF-based RSS (truly intended as syndication format).
     * @see \SimplePie\SimplePie::TYPE_RSS_ALL Any version of RSS.
     * @see \SimplePie\SimplePie::TYPE_ATOM_03 Atom 0.3.
     * @see \SimplePie\SimplePie::TYPE_ATOM_10 Atom 1.0.
     * @see \SimplePie\SimplePie::TYPE_ATOM_ALL Any version of Atom.
     * @see \SimplePie\SimplePie::TYPE_ALL Any known/supported feed type.
     * @return int \SimplePie\SimplePie::TYPE_* constant
     */
    public function get_type()
    {
        if (!isset($this-&gt;data['type'])) {
            $this-&gt;data['type'] = self::TYPE_ALL;
            if (isset($this-&gt;data['child'][self::NAMESPACE_ATOM_10]['feed'])) {
                $this-&gt;data['type'] &amp;= self::TYPE_ATOM_10;
            } elseif (isset($this-&gt;data['child'][self::NAMESPACE_ATOM_03]['feed'])) {
                $this-&gt;data['type'] &amp;= self::TYPE_ATOM_03;
            } elseif (isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'])) {
                if (isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_10]['channel'])
                || isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_10]['image'])
                || isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_10]['item'])
                || isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_10]['textinput'])) {
                    $this-&gt;data['type'] &amp;= self::TYPE_RSS_10;
                }
                if (isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_090]['channel'])
                || isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_090]['image'])
                || isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_090]['item'])
                || isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][self::NAMESPACE_RSS_090]['textinput'])) {
                    $this-&gt;data['type'] &amp;= self::TYPE_RSS_090;
                }
            } elseif (isset($this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'])) {
                $this-&gt;data['type'] &amp;= self::TYPE_RSS_ALL;
                if (isset($this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'][0]['attribs']['']['version'])) {
                    switch (trim($this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'][0]['attribs']['']['version'])) {
                        case '0.91':
                            $this-&gt;data['type'] &amp;= self::TYPE_RSS_091;
                            if (isset($this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'][0]['child'][self::NAMESPACE_RSS_20]['skiphours']['hour'][0]['data'])) {
                                switch (trim($this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'][0]['child'][self::NAMESPACE_RSS_20]['skiphours']['hour'][0]['data'])) {
                                    case '0':
                                        $this-&gt;data['type'] &amp;= self::TYPE_RSS_091_NETSCAPE;
                                        break;

                                    case '24':
                                        $this-&gt;data['type'] &amp;= self::TYPE_RSS_091_USERLAND;
                                        break;
                                }
                            }
                            break;

                        case '0.92':
                            $this-&gt;data['type'] &amp;= self::TYPE_RSS_092;
                            break;

                        case '0.93':
                            $this-&gt;data['type'] &amp;= self::TYPE_RSS_093;
                            break;

                        case '0.94':
                            $this-&gt;data['type'] &amp;= self::TYPE_RSS_094;
                            break;

                        case '2.0':
                            $this-&gt;data['type'] &amp;= self::TYPE_RSS_20;
                            break;
                    }
                }
            } else {
                $this-&gt;data['type'] = self::TYPE_NONE;
            }
        }
        return $this-&gt;data['type'];
    }

    /**
     * Get the URL for the feed
     *
     * When the 'permanent' mode is enabled, returns the original feed URL,
     * except in the case of an `HTTP 301 Moved Permanently` status response,
     * in which case the location of the first redirection is returned.
     *
     * When the 'permanent' mode is disabled (default),
     * may or may not be different from the URL passed to {@see set_feed_url()},
     * depending on whether auto-discovery was used, and whether there were
     * any redirects along the way.
     *
     * @since Preview Release (previously called `get_feed_url()` since SimplePie 0.8.)
     * @todo Support &lt;itunes:new-feed-url&gt;
     * @todo Also, |atom:link|@rel=self
     * @param bool $permanent Permanent mode to return only the original URL or the first redirection
     * iff it is a 301 redirection
     * @return string|null
     */
    public function subscribe_url($permanent = false)
    {
        if ($permanent) {
            if ($this-&gt;permanent_url !== null) {
                // sanitize encodes ampersands which are required when used in a url.
                return str_replace(
                    '&amp;amp;',
                    '&amp;',
                    $this-&gt;sanitize(
                        $this-&gt;permanent_url,
                        self::CONSTRUCT_IRI
                    )
                );
            }
        } else {
            if ($this-&gt;feed_url !== null) {
                return str_replace(
                    '&amp;amp;',
                    '&amp;',
                    $this-&gt;sanitize(
                        $this-&gt;feed_url,
                        self::CONSTRUCT_IRI
                    )
                );
            }
        }
        return null;
    }

    /**
     * Get data for an feed-level element
     *
     * This method allows you to get access to ANY element/attribute that is a
     * sub-element of the opening feed tag.
     *
     * The return value is an indexed array of elements matching the given
     * namespace and tag name. Each element has `attribs`, `data` and `child`
     * subkeys. For `attribs` and `child`, these contain namespace subkeys.
     * `attribs` then has one level of associative name =&gt; value data (where
     * `value` is a string) after the namespace. `child` has tag-indexed keys
     * after the namespace, each member of which is an indexed array matching
     * this same format.
     *
     * For example:
     * &lt;pre&gt;
     * // This is probably a bad example because we already support
     * // &lt;media:content&gt; natively, but it shows you how to parse through
     * // the nodes.
     * $group = $item-&gt;get_item_tags(\SimplePie\SimplePie::NAMESPACE_MEDIARSS, 'group');
     * $content = $group[0]['child'][\SimplePie\SimplePie::NAMESPACE_MEDIARSS]['content'];
     * $file = $content[0]['attribs']['']['url'];
     * echo $file;
     * &lt;/pre&gt;
     *
     * @since 1.0
     * @see http://simplepie.org/wiki/faq/supported_xml_namespaces
     * @param string $namespace The URL of the XML namespace of the elements you're trying to access
     * @param string $tag Tag name
     * @return array
     */
    public function get_feed_tags($namespace, $tag)
    {
        $type = $this-&gt;get_type();
        if ($type &amp; self::TYPE_ATOM_10) {
            if (isset($this-&gt;data['child'][self::NAMESPACE_ATOM_10]['feed'][0]['child'][$namespace][$tag])) {
                return $this-&gt;data['child'][self::NAMESPACE_ATOM_10]['feed'][0]['child'][$namespace][$tag];
            }
        }
        if ($type &amp; self::TYPE_ATOM_03) {
            if (isset($this-&gt;data['child'][self::NAMESPACE_ATOM_03]['feed'][0]['child'][$namespace][$tag])) {
                return $this-&gt;data['child'][self::NAMESPACE_ATOM_03]['feed'][0]['child'][$namespace][$tag];
            }
        }
        if ($type &amp; self::TYPE_RSS_RDF) {
            if (isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][$namespace][$tag])) {
                return $this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['child'][$namespace][$tag];
            }
        }
        if ($type &amp; self::TYPE_RSS_SYNDICATION) {
            if (isset($this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'][0]['child'][$namespace][$tag])) {
                return $this-&gt;data['child'][self::NAMESPACE_RSS_20]['rss'][0]['child'][$namespace][$tag];
            }
        }
        return null;
    }

    /**
     * Get data for an channel-level element
     *
     * This method allows you to get access to ANY element/attribute in the
     * channel/header section of the feed.
     *
     * See {@see SimplePie::get_feed_tags()} for a description of the return value
     *
     * @since 1.0
     * @see http://simplepie.org/wiki/faq/supported_xml_namespaces
     * @param string $namespace The URL of the XML namespace of the elements you're trying to access
     * @param string $tag Tag name
     * @return array
     */
    public function get_channel_tags($namespace, $tag)
    {
        $type = $this-&gt;get_type();
        if ($type &amp; self::TYPE_ATOM_ALL) {
            if ($return = $this-&gt;get_feed_tags($namespace, $tag)) {
                return $return;
            }
        }
        if ($type &amp; self::TYPE_RSS_10) {
            if ($channel = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_10, 'channel')) {
                if (isset($channel[0]['child'][$namespace][$tag])) {
                    return $channel[0]['child'][$namespace][$tag];
                }
            }
        }
        if ($type &amp; self::TYPE_RSS_090) {
            if ($channel = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_090, 'channel')) {
                if (isset($channel[0]['child'][$namespace][$tag])) {
                    return $channel[0]['child'][$namespace][$tag];
                }
            }
        }
        if ($type &amp; self::TYPE_RSS_SYNDICATION) {
            if ($channel = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_20, 'channel')) {
                if (isset($channel[0]['child'][$namespace][$tag])) {
                    return $channel[0]['child'][$namespace][$tag];
                }
            }
        }
        return null;
    }

    /**
     * Get data for an channel-level element
     *
     * This method allows you to get access to ANY element/attribute in the
     * image/logo section of the feed.
     *
     * See {@see SimplePie::get_feed_tags()} for a description of the return value
     *
     * @since 1.0
     * @see http://simplepie.org/wiki/faq/supported_xml_namespaces
     * @param string $namespace The URL of the XML namespace of the elements you're trying to access
     * @param string $tag Tag name
     * @return array
     */
    public function get_image_tags($namespace, $tag)
    {
        $type = $this-&gt;get_type();
        if ($type &amp; self::TYPE_RSS_10) {
            if ($image = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_10, 'image')) {
                if (isset($image[0]['child'][$namespace][$tag])) {
                    return $image[0]['child'][$namespace][$tag];
                }
            }
        }
        if ($type &amp; self::TYPE_RSS_090) {
            if ($image = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_090, 'image')) {
                if (isset($image[0]['child'][$namespace][$tag])) {
                    return $image[0]['child'][$namespace][$tag];
                }
            }
        }
        if ($type &amp; self::TYPE_RSS_SYNDICATION) {
            if ($image = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'image')) {
                if (isset($image[0]['child'][$namespace][$tag])) {
                    return $image[0]['child'][$namespace][$tag];
                }
            }
        }
        return null;
    }

    /**
     * Get the base URL value from the feed
     *
     * Uses `&lt;xml:base&gt;` if available, otherwise uses the first link in the
     * feed, or failing that, the URL of the feed itself.
     *
     * @see get_link
     * @see subscribe_url
     *
     * @param array $element
     * @return string
     */
    public function get_base($element = [])
    {
        if (!empty($element['xml_base_explicit']) &amp;&amp; isset($element['xml_base'])) {
            return $element['xml_base'];
        } elseif ($this-&gt;get_link() !== null) {
            return $this-&gt;get_link();
        }

        return $this-&gt;subscribe_url();
    }

    /**
     * Sanitize feed data
     *
     * @access private
     * @see \SimplePie\Sanitize::sanitize()
     * @param string $data Data to sanitize
     * @param int $type One of the \SimplePie\SimplePie::CONSTRUCT_* constants
     * @param string $base Base URL to resolve URLs against
     * @return string Sanitized data
     */
    public function sanitize($data, $type, $base = '')
    {
        try {
            return $this-&gt;sanitize-&gt;sanitize($data, $type, $base);
        } catch (\SimplePie\Exception $e) {
            if (!$this-&gt;enable_exceptions) {
                $this-&gt;error = $e-&gt;getMessage();
                $this-&gt;registry-&gt;call(Misc::class, 'error', [$this-&gt;error, E_USER_WARNING, $e-&gt;getFile(), $e-&gt;getLine()]);
                return '';
            }

            throw $e;
        }
    }

    /**
     * Get the title of the feed
     *
     * Uses `&lt;atom:title&gt;`, `&lt;title&gt;` or `&lt;dc:title&gt;`
     *
     * @since 1.0 (previously called `get_feed_title` since 0.8)
     * @return string|null
     */
    public function get_title()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], $this-&gt;registry-&gt;call(Misc::class, 'atom_10_construct_type', [$return[0]['attribs']]), $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_03, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], $this-&gt;registry-&gt;call(Misc::class, 'atom_03_construct_type', [$return[0]['attribs']]), $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_10, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_MAYBE_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_090, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_MAYBE_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_MAYBE_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_11, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_10, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        }

        return null;
    }

    /**
     * Get a category for the feed
     *
     * @since Unknown
     * @param int $key The category that you want to return. Remember that arrays begin with 0, not 1
     * @return \SimplePie\Category|null
     */
    public function get_category($key = 0)
    {
        $categories = $this-&gt;get_categories();
        if (isset($categories[$key])) {
            return $categories[$key];
        }

        return null;
    }

    /**
     * Get all categories for the feed
     *
     * Uses `&lt;atom:category&gt;`, `&lt;category&gt;` or `&lt;dc:subject&gt;`
     *
     * @since Unknown
     * @return array|null List of {@see \SimplePie\Category} objects
     */
    public function get_categories()
    {
        $categories = [];

        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'category') as $category) {
            $term = null;
            $scheme = null;
            $label = null;
            if (isset($category['attribs']['']['term'])) {
                $term = $this-&gt;sanitize($category['attribs']['']['term'], self::CONSTRUCT_TEXT);
            }
            if (isset($category['attribs']['']['scheme'])) {
                $scheme = $this-&gt;sanitize($category['attribs']['']['scheme'], self::CONSTRUCT_TEXT);
            }
            if (isset($category['attribs']['']['label'])) {
                $label = $this-&gt;sanitize($category['attribs']['']['label'], self::CONSTRUCT_TEXT);
            }
            $categories[] = $this-&gt;registry-&gt;create(Category::class, [$term, $scheme, $label]);
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'category') as $category) {
            // This is really the label, but keep this as the term also for BC.
            // Label will also work on retrieving because that falls back to term.
            $term = $this-&gt;sanitize($category['data'], self::CONSTRUCT_TEXT);
            if (isset($category['attribs']['']['domain'])) {
                $scheme = $this-&gt;sanitize($category['attribs']['']['domain'], self::CONSTRUCT_TEXT);
            } else {
                $scheme = null;
            }
            $categories[] = $this-&gt;registry-&gt;create(Category::class, [$term, $scheme, null]);
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_DC_11, 'subject') as $category) {
            $categories[] = $this-&gt;registry-&gt;create(Category::class, [$this-&gt;sanitize($category['data'], self::CONSTRUCT_TEXT), null, null]);
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_DC_10, 'subject') as $category) {
            $categories[] = $this-&gt;registry-&gt;create(Category::class, [$this-&gt;sanitize($category['data'], self::CONSTRUCT_TEXT), null, null]);
        }

        if (!empty($categories)) {
            return array_unique($categories);
        }

        return null;
    }

    /**
     * Get an author for the feed
     *
     * @since 1.1
     * @param int $key The author that you want to return. Remember that arrays begin with 0, not 1
     * @return \SimplePie\Author|null
     */
    public function get_author($key = 0)
    {
        $authors = $this-&gt;get_authors();
        if (isset($authors[$key])) {
            return $authors[$key];
        }

        return null;
    }

    /**
     * Get all authors for the feed
     *
     * Uses `&lt;atom:author&gt;`, `&lt;author&gt;`, `&lt;dc:creator&gt;` or `&lt;itunes:author&gt;`
     *
     * @since 1.1
     * @return array|null List of {@see \SimplePie\Author} objects
     */
    public function get_authors()
    {
        $authors = [];
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'author') as $author) {
            $name = null;
            $uri = null;
            $email = null;
            if (isset($author['child'][self::NAMESPACE_ATOM_10]['name'][0]['data'])) {
                $name = $this-&gt;sanitize($author['child'][self::NAMESPACE_ATOM_10]['name'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if (isset($author['child'][self::NAMESPACE_ATOM_10]['uri'][0]['data'])) {
                $uri = $this-&gt;sanitize($author['child'][self::NAMESPACE_ATOM_10]['uri'][0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($author['child'][self::NAMESPACE_ATOM_10]['uri'][0]));
            }
            if (isset($author['child'][self::NAMESPACE_ATOM_10]['email'][0]['data'])) {
                $email = $this-&gt;sanitize($author['child'][self::NAMESPACE_ATOM_10]['email'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if ($name !== null || $email !== null || $uri !== null) {
                $authors[] = $this-&gt;registry-&gt;create(Author::class, [$name, $uri, $email]);
            }
        }
        if ($author = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_03, 'author')) {
            $name = null;
            $url = null;
            $email = null;
            if (isset($author[0]['child'][self::NAMESPACE_ATOM_03]['name'][0]['data'])) {
                $name = $this-&gt;sanitize($author[0]['child'][self::NAMESPACE_ATOM_03]['name'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if (isset($author[0]['child'][self::NAMESPACE_ATOM_03]['url'][0]['data'])) {
                $url = $this-&gt;sanitize($author[0]['child'][self::NAMESPACE_ATOM_03]['url'][0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($author[0]['child'][self::NAMESPACE_ATOM_03]['url'][0]));
            }
            if (isset($author[0]['child'][self::NAMESPACE_ATOM_03]['email'][0]['data'])) {
                $email = $this-&gt;sanitize($author[0]['child'][self::NAMESPACE_ATOM_03]['email'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if ($name !== null || $email !== null || $url !== null) {
                $authors[] = $this-&gt;registry-&gt;create(Author::class, [$name, $url, $email]);
            }
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_DC_11, 'creator') as $author) {
            $authors[] = $this-&gt;registry-&gt;create(Author::class, [$this-&gt;sanitize($author['data'], self::CONSTRUCT_TEXT), null, null]);
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_DC_10, 'creator') as $author) {
            $authors[] = $this-&gt;registry-&gt;create(Author::class, [$this-&gt;sanitize($author['data'], self::CONSTRUCT_TEXT), null, null]);
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_ITUNES, 'author') as $author) {
            $authors[] = $this-&gt;registry-&gt;create(Author::class, [$this-&gt;sanitize($author['data'], self::CONSTRUCT_TEXT), null, null]);
        }

        if (!empty($authors)) {
            return array_unique($authors);
        }

        return null;
    }

    /**
     * Get a contributor for the feed
     *
     * @since 1.1
     * @param int $key The contrbutor that you want to return. Remember that arrays begin with 0, not 1
     * @return \SimplePie\Author|null
     */
    public function get_contributor($key = 0)
    {
        $contributors = $this-&gt;get_contributors();
        if (isset($contributors[$key])) {
            return $contributors[$key];
        }

        return null;
    }

    /**
     * Get all contributors for the feed
     *
     * Uses `&lt;atom:contributor&gt;`
     *
     * @since 1.1
     * @return array|null List of {@see \SimplePie\Author} objects
     */
    public function get_contributors()
    {
        $contributors = [];
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'contributor') as $contributor) {
            $name = null;
            $uri = null;
            $email = null;
            if (isset($contributor['child'][self::NAMESPACE_ATOM_10]['name'][0]['data'])) {
                $name = $this-&gt;sanitize($contributor['child'][self::NAMESPACE_ATOM_10]['name'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if (isset($contributor['child'][self::NAMESPACE_ATOM_10]['uri'][0]['data'])) {
                $uri = $this-&gt;sanitize($contributor['child'][self::NAMESPACE_ATOM_10]['uri'][0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($contributor['child'][self::NAMESPACE_ATOM_10]['uri'][0]));
            }
            if (isset($contributor['child'][self::NAMESPACE_ATOM_10]['email'][0]['data'])) {
                $email = $this-&gt;sanitize($contributor['child'][self::NAMESPACE_ATOM_10]['email'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if ($name !== null || $email !== null || $uri !== null) {
                $contributors[] = $this-&gt;registry-&gt;create(Author::class, [$name, $uri, $email]);
            }
        }
        foreach ((array) $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_03, 'contributor') as $contributor) {
            $name = null;
            $url = null;
            $email = null;
            if (isset($contributor['child'][self::NAMESPACE_ATOM_03]['name'][0]['data'])) {
                $name = $this-&gt;sanitize($contributor['child'][self::NAMESPACE_ATOM_03]['name'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if (isset($contributor['child'][self::NAMESPACE_ATOM_03]['url'][0]['data'])) {
                $url = $this-&gt;sanitize($contributor['child'][self::NAMESPACE_ATOM_03]['url'][0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($contributor['child'][self::NAMESPACE_ATOM_03]['url'][0]));
            }
            if (isset($contributor['child'][self::NAMESPACE_ATOM_03]['email'][0]['data'])) {
                $email = $this-&gt;sanitize($contributor['child'][self::NAMESPACE_ATOM_03]['email'][0]['data'], self::CONSTRUCT_TEXT);
            }
            if ($name !== null || $email !== null || $url !== null) {
                $contributors[] = $this-&gt;registry-&gt;create(Author::class, [$name, $url, $email]);
            }
        }

        if (!empty($contributors)) {
            return array_unique($contributors);
        }

        return null;
    }

    /**
     * Get a single link for the feed
     *
     * @since 1.0 (previously called `get_feed_link` since Preview Release, `get_feed_permalink()` since 0.8)
     * @param int $key The link that you want to return. Remember that arrays begin with 0, not 1
     * @param string $rel The relationship of the link to return
     * @return string|null Link URL
     */
    public function get_link($key = 0, $rel = 'alternate')
    {
        $links = $this-&gt;get_links($rel);
        if (isset($links[$key])) {
            return $links[$key];
        }

        return null;
    }

    /**
     * Get the permalink for the item
     *
     * Returns the first link available with a relationship of &quot;alternate&quot;.
     * Identical to {@see get_link()} with key 0
     *
     * @see get_link
     * @since 1.0 (previously called `get_feed_link` since Preview Release, `get_feed_permalink()` since 0.8)
     * @internal Added for parity between the parent-level and the item/entry-level.
     * @return string|null Link URL
     */
    public function get_permalink()
    {
        return $this-&gt;get_link(0);
    }

    /**
     * Get all links for the feed
     *
     * Uses `&lt;atom:link&gt;` or `&lt;link&gt;`
     *
     * @since Beta 2
     * @param string $rel The relationship of links to return
     * @return array|null Links found for the feed (strings)
     */
    public function get_links($rel = 'alternate')
    {
        if (!isset($this-&gt;data['links'])) {
            $this-&gt;data['links'] = [];
            if ($links = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'link')) {
                foreach ($links as $link) {
                    if (isset($link['attribs']['']['href'])) {
                        $link_rel = (isset($link['attribs']['']['rel'])) ? $link['attribs']['']['rel'] : 'alternate';
                        $this-&gt;data['links'][$link_rel][] = $this-&gt;sanitize($link['attribs']['']['href'], self::CONSTRUCT_IRI, $this-&gt;get_base($link));
                    }
                }
            }
            if ($links = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_03, 'link')) {
                foreach ($links as $link) {
                    if (isset($link['attribs']['']['href'])) {
                        $link_rel = (isset($link['attribs']['']['rel'])) ? $link['attribs']['']['rel'] : 'alternate';
                        $this-&gt;data['links'][$link_rel][] = $this-&gt;sanitize($link['attribs']['']['href'], self::CONSTRUCT_IRI, $this-&gt;get_base($link));
                    }
                }
            }
            if ($links = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_10, 'link')) {
                $this-&gt;data['links']['alternate'][] = $this-&gt;sanitize($links[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($links[0]));
            }
            if ($links = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_090, 'link')) {
                $this-&gt;data['links']['alternate'][] = $this-&gt;sanitize($links[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($links[0]));
            }
            if ($links = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'link')) {
                $this-&gt;data['links']['alternate'][] = $this-&gt;sanitize($links[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($links[0]));
            }

            $keys = array_keys($this-&gt;data['links']);
            foreach ($keys as $key) {
                if ($this-&gt;registry-&gt;call(Misc::class, 'is_isegment_nz_nc', [$key])) {
                    if (isset($this-&gt;data['links'][self::IANA_LINK_RELATIONS_REGISTRY . $key])) {
                        $this-&gt;data['links'][self::IANA_LINK_RELATIONS_REGISTRY . $key] = array_merge($this-&gt;data['links'][$key], $this-&gt;data['links'][self::IANA_LINK_RELATIONS_REGISTRY . $key]);
                        $this-&gt;data['links'][$key] = &amp;$this-&gt;data['links'][self::IANA_LINK_RELATIONS_REGISTRY . $key];
                    } else {
                        $this-&gt;data['links'][self::IANA_LINK_RELATIONS_REGISTRY . $key] = &amp;$this-&gt;data['links'][$key];
                    }
                } elseif (substr($key, 0, 41) === self::IANA_LINK_RELATIONS_REGISTRY) {
                    $this-&gt;data['links'][substr($key, 41)] = &amp;$this-&gt;data['links'][$key];
                }
                $this-&gt;data['links'][$key] = array_unique($this-&gt;data['links'][$key]);
            }
        }

        if (isset($this-&gt;data['headers']['link'])) {
            $link_headers = $this-&gt;data['headers']['link'];
            if (is_array($link_headers)) {
                $link_headers = implode(',', $link_headers);
            }
            // https://datatracker.ietf.org/doc/html/rfc8288
            if (is_string($link_headers) &amp;&amp;
                preg_match_all('/&lt;(?P&lt;uri&gt;[^&gt;]+)&gt;\s*;\s*rel\s*=\s*(?P&lt;quote&gt;&quot;?)' . preg_quote($rel) . '(?P=quote)\s*(?=,|$)/i', $link_headers, $matches)) {
                return $matches['uri'];
            }
        }

        if (isset($this-&gt;data['links'][$rel])) {
            return $this-&gt;data['links'][$rel];
        }

        return null;
    }

    public function get_all_discovered_feeds()
    {
        return $this-&gt;all_discovered_feeds;
    }

    /**
     * Get the content for the item
     *
     * Uses `&lt;atom:subtitle&gt;`, `&lt;atom:tagline&gt;`, `&lt;description&gt;`,
     * `&lt;dc:description&gt;`, `&lt;itunes:summary&gt;` or `&lt;itunes:subtitle&gt;`
     *
     * @since 1.0 (previously called `get_feed_description()` since 0.8)
     * @return string|null
     */
    public function get_description()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'subtitle')) {
            return $this-&gt;sanitize($return[0]['data'], $this-&gt;registry-&gt;call(Misc::class, 'atom_10_construct_type', [$return[0]['attribs']]), $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_03, 'tagline')) {
            return $this-&gt;sanitize($return[0]['data'], $this-&gt;registry-&gt;call(Misc::class, 'atom_03_construct_type', [$return[0]['attribs']]), $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_10, 'description')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_MAYBE_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_090, 'description')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_MAYBE_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'description')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_11, 'description')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_10, 'description')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ITUNES, 'summary')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_HTML, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ITUNES, 'subtitle')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_HTML, $this-&gt;get_base($return[0]));
        }

        return null;
    }

    /**
     * Get the copyright info for the feed
     *
     * Uses `&lt;atom:rights&gt;`, `&lt;atom:copyright&gt;` or `&lt;dc:rights&gt;`
     *
     * @since 1.0 (previously called `get_feed_copyright()` since 0.8)
     * @return string|null
     */
    public function get_copyright()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'rights')) {
            return $this-&gt;sanitize($return[0]['data'], $this-&gt;registry-&gt;call(Misc::class, 'atom_10_construct_type', [$return[0]['attribs']]), $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_03, 'copyright')) {
            return $this-&gt;sanitize($return[0]['data'], $this-&gt;registry-&gt;call(Misc::class, 'atom_03_construct_type', [$return[0]['attribs']]), $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'copyright')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_11, 'rights')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_10, 'rights')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        }

        return null;
    }

    /**
     * Get the language for the feed
     *
     * Uses `&lt;language&gt;`, `&lt;dc:language&gt;`, or @xml_lang
     *
     * @since 1.0 (previously called `get_feed_language()` since 0.8)
     * @return string|null
     */
    public function get_language()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'language')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_11, 'language')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_DC_10, 'language')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif (isset($this-&gt;data['child'][self::NAMESPACE_ATOM_10]['feed'][0]['xml_lang'])) {
            return $this-&gt;sanitize($this-&gt;data['child'][self::NAMESPACE_ATOM_10]['feed'][0]['xml_lang'], self::CONSTRUCT_TEXT);
        } elseif (isset($this-&gt;data['child'][self::NAMESPACE_ATOM_03]['feed'][0]['xml_lang'])) {
            return $this-&gt;sanitize($this-&gt;data['child'][self::NAMESPACE_ATOM_03]['feed'][0]['xml_lang'], self::CONSTRUCT_TEXT);
        } elseif (isset($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['xml_lang'])) {
            return $this-&gt;sanitize($this-&gt;data['child'][self::NAMESPACE_RDF]['RDF'][0]['xml_lang'], self::CONSTRUCT_TEXT);
        } elseif (isset($this-&gt;data['headers']['content-language'])) {
            return $this-&gt;sanitize($this-&gt;data['headers']['content-language'], self::CONSTRUCT_TEXT);
        }

        return null;
    }

    /**
     * Get the latitude coordinates for the item
     *
     * Compatible with the W3C WGS84 Basic Geo and GeoRSS specifications
     *
     * Uses `&lt;geo:lat&gt;` or `&lt;georss:point&gt;`
     *
     * @since 1.0
     * @link http://www.w3.org/2003/01/geo/ W3C WGS84 Basic Geo
     * @link http://www.georss.org/ GeoRSS
     * @return string|null
     */
    public function get_latitude()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_W3C_BASIC_GEO, 'lat')) {
            return (float) $return[0]['data'];
        } elseif (($return = $this-&gt;get_channel_tags(self::NAMESPACE_GEORSS, 'point')) &amp;&amp; preg_match('/^((?:-)?[0-9]+(?:\.[0-9]+)) ((?:-)?[0-9]+(?:\.[0-9]+))$/', trim($return[0]['data']), $match)) {
            return (float) $match[1];
        }

        return null;
    }

    /**
     * Get the longitude coordinates for the feed
     *
     * Compatible with the W3C WGS84 Basic Geo and GeoRSS specifications
     *
     * Uses `&lt;geo:long&gt;`, `&lt;geo:lon&gt;` or `&lt;georss:point&gt;`
     *
     * @since 1.0
     * @link http://www.w3.org/2003/01/geo/ W3C WGS84 Basic Geo
     * @link http://www.georss.org/ GeoRSS
     * @return string|null
     */
    public function get_longitude()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_W3C_BASIC_GEO, 'long')) {
            return (float) $return[0]['data'];
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_W3C_BASIC_GEO, 'lon')) {
            return (float) $return[0]['data'];
        } elseif (($return = $this-&gt;get_channel_tags(self::NAMESPACE_GEORSS, 'point')) &amp;&amp; preg_match('/^((?:-)?[0-9]+(?:\.[0-9]+)) ((?:-)?[0-9]+(?:\.[0-9]+))$/', trim($return[0]['data']), $match)) {
            return (float) $match[2];
        }

        return null;
    }

    /**
     * Get the feed logo's title
     *
     * RSS 0.9.0, 1.0 and 2.0 feeds are allowed to have a &quot;feed logo&quot; title.
     *
     * Uses `&lt;image&gt;&lt;title&gt;` or `&lt;image&gt;&lt;dc:title&gt;`
     *
     * @return string|null
     */
    public function get_image_title()
    {
        if ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_10, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_090, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_DC_11, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_DC_10, 'title')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_TEXT);
        }

        return null;
    }

    /**
     * Get the feed logo's URL
     *
     * RSS 0.9.0, 2.0, Atom 1.0, and feeds with iTunes RSS tags are allowed to
     * have a &quot;feed logo&quot; URL. This points directly to the image itself.
     *
     * Uses `&lt;itunes:image&gt;`, `&lt;atom:logo&gt;`, `&lt;atom:icon&gt;`,
     * `&lt;image&gt;&lt;title&gt;` or `&lt;image&gt;&lt;dc:title&gt;`
     *
     * @return string|null
     */
    public function get_image_url()
    {
        if ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ITUNES, 'image')) {
            return $this-&gt;sanitize($return[0]['attribs']['']['href'], self::CONSTRUCT_IRI);
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'logo')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_channel_tags(self::NAMESPACE_ATOM_10, 'icon')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_10, 'url')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_090, 'url')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'url')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        }

        return null;
    }


    /**
     * Get the feed logo's link
     *
     * RSS 0.9.0, 1.0 and 2.0 feeds are allowed to have a &quot;feed logo&quot; link. This
     * points to a human-readable page that the image should link to.
     *
     * Uses `&lt;itunes:image&gt;`, `&lt;atom:logo&gt;`, `&lt;atom:icon&gt;`,
     * `&lt;image&gt;&lt;title&gt;` or `&lt;image&gt;&lt;dc:title&gt;`
     *
     * @return string|null
     */
    public function get_image_link()
    {
        if ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_10, 'link')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_090, 'link')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        } elseif ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'link')) {
            return $this-&gt;sanitize($return[0]['data'], self::CONSTRUCT_IRI, $this-&gt;get_base($return[0]));
        }

        return null;
    }

    /**
     * Get the feed logo's link
     *
     * RSS 2.0 feeds are allowed to have a &quot;feed logo&quot; width.
     *
     * Uses `&lt;image&gt;&lt;width&gt;` or defaults to 88 if no width is specified and
     * the feed is an RSS 2.0 feed.
     *
     * @return int|null
     */
    public function get_image_width()
    {
        if ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'width')) {
            return intval($return[0]['data']);
        } elseif ($this-&gt;get_type() &amp; self::TYPE_RSS_SYNDICATION &amp;&amp; $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'url')) {
            return 88;
        }

        return null;
    }

    /**
     * Get the feed logo's height
     *
     * RSS 2.0 feeds are allowed to have a &quot;feed logo&quot; height.
     *
     * Uses `&lt;image&gt;&lt;height&gt;` or defaults to 31 if no height is specified and
     * the feed is an RSS 2.0 feed.
     *
     * @return int|null
     */
    public function get_image_height()
    {
        if ($return = $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'height')) {
            return intval($return[0]['data']);
        } elseif ($this-&gt;get_type() &amp; self::TYPE_RSS_SYNDICATION &amp;&amp; $this-&gt;get_image_tags(self::NAMESPACE_RSS_20, 'url')) {
            return 31;
        }

        return null;
    }

    /**
     * Get the number of items in the feed
     *
     * This is well-suited for {@link http://php.net/for for()} loops with
     * {@see get_item()}
     *
     * @param int $max Maximum value to return. 0 for no limit
     * @return int Number of items in the feed
     */
    public function get_item_quantity($max = 0)
    {
        $max = (int) $max;
        $qty = count($this-&gt;get_items());
        if ($max === 0) {
            return $qty;
        }

        return ($qty &gt; $max) ? $max : $qty;
    }

    /**
     * Get a single item from the feed
     *
     * This is better suited for {@link http://php.net/for for()} loops, whereas
     * {@see get_items()} is better suited for
     * {@link http://php.net/foreach foreach()} loops.
     *
     * @see get_item_quantity()
     * @since Beta 2
     * @param int $key The item that you want to return. Remember that arrays begin with 0, not 1
     * @return \SimplePie\Item|null
     */
    public function get_item($key = 0)
    {
        $items = $this-&gt;get_items();
        if (isset($items[$key])) {
            return $items[$key];
        }

        return null;
    }

    /**
     * Get all items from the feed
     *
     * This is better suited for {@link http://php.net/for for()} loops, whereas
     * {@see get_items()} is better suited for
     * {@link http://php.net/foreach foreach()} loops.
     *
     * @see get_item_quantity
     * @since Beta 2
     * @param int $start Index to start at
     * @param int $end Number of items to return. 0 for all items after `$start`
     * @return \SimplePie\Item[]|null List of {@see \SimplePie\Item} objects
     */
    public function get_items($start = 0, $end = 0)
    {
        if (!isset($this-&gt;data['items'])) {
            if (!empty($this-&gt;multifeed_objects)) {
                $this-&gt;data['items'] = SimplePie::merge_items($this-&gt;multifeed_objects, $start, $end, $this-&gt;item_limit);
                if (empty($this-&gt;data['items'])) {
                    return [];
                }
                return $this-&gt;data['items'];
            }
            $this-&gt;data['items'] = [];
            if ($items = $this-&gt;get_feed_tags(self::NAMESPACE_ATOM_10, 'entry')) {
                $keys = array_keys($items);
                foreach ($keys as $key) {
                    $this-&gt;data['items'][] = $this-&gt;registry-&gt;create(Item::class, [$this, $items[$key]]);
                }
            }
            if ($items = $this-&gt;get_feed_tags(self::NAMESPACE_ATOM_03, 'entry')) {
                $keys = array_keys($items);
                foreach ($keys as $key) {
                    $this-&gt;data['items'][] = $this-&gt;registry-&gt;create(Item::class, [$this, $items[$key]]);
                }
            }
            if ($items = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_10, 'item')) {
                $keys = array_keys($items);
                foreach ($keys as $key) {
                    $this-&gt;data['items'][] = $this-&gt;registry-&gt;create(Item::class, [$this, $items[$key]]);
                }
            }
            if ($items = $this-&gt;get_feed_tags(self::NAMESPACE_RSS_090, 'item')) {
                $keys = array_keys($items);
                foreach ($keys as $key) {
                    $this-&gt;data['items'][] = $this-&gt;registry-&gt;create(Item::class, [$this, $items[$key]]);
                }
            }
            if ($items = $this-&gt;get_channel_tags(self::NAMESPACE_RSS_20, 'item')) {
                $keys = array_keys($items);
                foreach ($keys as $key) {
                    $this-&gt;data['items'][] = $this-&gt;registry-&gt;create(Item::class, [$this, $items[$key]]);
                }
            }
        }

        if (empty($this-&gt;data['items'])) {
            return [];
        }

        if ($this-&gt;order_by_date) {
            if (!isset($this-&gt;data['ordered_items'])) {
                $this-&gt;data['ordered_items'] = $this-&gt;data['items'];
                usort($this-&gt;data['ordered_items'], [get_class($this), 'sort_items']);
            }
            $items = $this-&gt;data['ordered_items'];
        } else {
            $items = $this-&gt;data['items'];
        }
        // Slice the data as desired
        if ($end === 0) {
            return array_slice($items, $start);
        }

        return array_slice($items, $start, $end);
    }

    /**
     * Set the favicon handler
     *
     * @deprecated Use your own favicon handling instead
     */
    public function set_favicon_handler($page = false, $qs = 'i')
    {
        trigger_error('Favicon handling has been removed, please use your own handling', \E_USER_DEPRECATED);
        return false;
    }

    /**
     * Get the favicon for the current feed
     *
     * @deprecated Use your own favicon handling instead
     */
    public function get_favicon()
    {
        trigger_error('Favicon handling has been removed, please use your own handling', \E_USER_DEPRECATED);

        if (($url = $this-&gt;get_link()) !== null) {
            return 'https://www.google.com/s2/favicons?domain=' . urlencode($url);
        }

        return false;
    }

    /**
     * Magic method handler
     *
     * @param string $method Method name
     * @param array $args Arguments to the method
     * @return mixed
     */
    public function __call($method, $args)
    {
        if (strpos($method, 'subscribe_') === 0) {
            trigger_error('subscribe_*() has been deprecated, implement the callback yourself', \E_USER_DEPRECATED);
            return '';
        }
        if ($method === 'enable_xml_dump') {
            trigger_error('enable_xml_dump() has been deprecated, use get_raw_data() instead', \E_USER_DEPRECATED);
            return false;
        }

        $class = get_class($this);
        $trace = debug_backtrace(); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
        $file = $trace[0]['file'];
        $line = $trace[0]['line'];
        throw new SimplePieException(&quot;Call to undefined method $class::$method() in $file on line $line&quot;);
    }

    /**
     * Sorting callback for items
     *
     * @access private
     * @param SimplePie $a
     * @param SimplePie $b
     * @return boolean
     */
    public static function sort_items($a, $b)
    {
        $a_date = $a-&gt;get_date('U');
        $b_date = $b-&gt;get_date('U');
        if ($a_date &amp;&amp; $b_date) {
            return $a_date &gt; $b_date ? -1 : 1;
        }
        // Sort items without dates to the top.
        if ($a_date) {
            return 1;
        }
        if ($b_date) {
            return -1;
        }
        return 0;
    }

    /**
     * Merge items from several feeds into one
     *
     * If you're merging multiple feeds together, they need to all have dates
     * for the items or else SimplePie will refuse to sort them.
     *
     * @link http://simplepie.org/wiki/tutorial/sort_multiple_feeds_by_time_and_date#if_feeds_require_separate_per-feed_settings
     * @param array $urls List of SimplePie feed objects to merge
     * @param int $start Starting item
     * @param int $end Number of items to return
     * @param int $limit Maximum number of items per feed
     * @return array
     */
    public static function merge_items($urls, $start = 0, $end = 0, $limit = 0)
    {
        if (is_array($urls) &amp;&amp; sizeof($urls) &gt; 0) {
            $items = [];
            foreach ($urls as $arg) {
                if ($arg instanceof SimplePie) {
                    $items = array_merge($items, $arg-&gt;get_items(0, $limit));
                } else {
                    trigger_error('Arguments must be SimplePie objects', E_USER_WARNING);
                }
            }

            usort($items, [get_class($urls[0]), 'sort_items']);

            if ($end === 0) {
                return array_slice($items, $start);
            }

            return array_slice($items, $start, $end);
        }

        trigger_error('Cannot merge zero SimplePie objects', E_USER_WARNING);
        return [];
    }

    /**
     * Store PubSubHubbub links as headers
     *
     * There is no way to find PuSH links in the body of a microformats feed,
     * so they are added to the headers when found, to be used later by get_links.
     * @param \SimplePie\File $file
     * @param string $hub
     * @param string $self
     */
    private function store_links(&amp;$file, $hub, $self)
    {
        if (isset($file-&gt;headers['link']['hub']) ||
              (isset($file-&gt;headers['link']) &amp;&amp;
               preg_match('/rel=hub/', $file-&gt;headers['link']))) {
            return;
        }

        if ($hub) {
            if (isset($file-&gt;headers['link'])) {
                if ($file-&gt;headers['link'] !== '') {
                    $file-&gt;headers['link'] = ', ';
                }
            } else {
                $file-&gt;headers['link'] = '';
            }
            $file-&gt;headers['link'] .= '&lt;'.$hub.'&gt;; rel=hub';
            if ($self) {
                $file-&gt;headers['link'] .= ', &lt;'.$self.'&gt;; rel=self';
            }
        }
    }

    /**
     * Get a DataCache
     *
     * @param string $feed_url Only needed for BC, can be removed in SimplePie 2.0.0
     *
     * @return DataCache
     */
    private function get_cache($feed_url = '')
    {
        if ($this-&gt;cache === null) {
            // @trigger_error(sprintf('Not providing as PSR-16 cache implementation is deprecated since SimplePie 1.8.0, please use &quot;SimplePie\SimplePie::set_cache()&quot;.'), \E_USER_DEPRECATED);
            $cache = $this-&gt;registry-&gt;call(Cache::class, 'get_handler', [
                $this-&gt;cache_location,
                $this-&gt;get_cache_filename($feed_url),
                Base::TYPE_FEED
            ]);

            return new BaseDataCache($cache);
        }

        return $this-&gt;cache;
    }
}

class_alias('SimplePie\SimplePie', 'SimplePie');
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