[BUG] Cannot add RSS feed on v4.1.3

[GH0STDATA]

Please complete the following tasks.

• Web browser cache cleared
• Link provided to install script if applicable
• Web browser, ruTorrent, PHP and OS version provided

Tell us about your environment

Web Browser: Brave 1.50.121 (Chromium 112.0.5615.138)
ruTorrent: v4.1.3
PHP: PHP 8.1.18
OS: Ubuntu 20.04.6 LTS

Tell us how you installed ruTorrent

I installed ruTorrent via this docker image: https://github.com/crazy-max/docker-rtorrent-rutorrent

Describe the bug

I cannot add new RSS feeds, and RSS feeds do not update at the interval I have set.

I get this error in the dev console when trying to add a new RSS feed:

Additional logs from Docker:

2023/04/30 02:00:49 [error] 557#557: *89 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught Error: Class "DOMDocument" not found in /var/www/rutorrent/plugins/rss/rss_reader.php:124

Stack trace:
#0 /var/www/rutorrent/plugins/rss/rss.php(169): rssXpath()
#1 /var/www/rutorrent/plugins/rss/rss.php(940): rRSS->fetch()
#2 /var/www/rutorrent/plugins/rss/rss.php(1157): rRSSManager->tryFetch()
#3 /var/www/rutorrent/plugins/rss/action.php(30): rRSSManager->add()

thrown in /var/www/rutorrent/plugins/rss/rss_reader.php on line 124" while reading response header from upstream, client: 172.20.0.6, server: , request: "POST /plugins/rss/action.php HTTP/1.1", upstream: "fastcgi://unix:/var/run/php-fpm/php-fpm.sock:", host: "REDACTED", referrer: "https://REDACTED/"

I've reverted back to v4.0.4 for the time being until this issue has been resolved.

Steps to reproduce

1. Install rtorrent-rutorrent via Docker
2. Log into rutorrent
3. Try to add RSS feed

Expected behavior

RSS feeds should be added successfully and updated at the interval that I have chosen.

Additional context

No response

[GH0STDATA]

This bug be related to #2496, but I'm not 100% sure.

[boomboxnation]

While the new commit does now let me add new RSS and update existing, it is trying to load the <guid> rather than the <link> from the feed's <item> section, which in my case fails to load.

[TrimmingFool]

Before, <guid> was only used if <link> did not exist.

ruTorrent/plugins/rss/rss.php

Lines 208 to 219 in 6429984

	$href = '';
	if(array_key_exists('enclosure',$item))
	$href = $item['enclosure'];
	else
	if(array_key_exists('link',$item))
	$href = $item['link'];
	else
	if(array_key_exists('guid',$item))
	$href = $item['guid'];
	else
	if(array_key_exists('source',$item))
	$href = $item['source'];

Now, if <guid> is a valid url (i.e. matching a (http) url pattern) and <link> is not, <guid> is used.

ruTorrent/plugins/rss/rss.php

Lines 210 to 223 in 81d360b

	// expect permalink in guid and normal link in url
	$httpLinkExpr = '|^http(s)?://[a-z0-9-]+(.[a-z0-9-]+)*(:[0-9]+)?(/.*)?$|i';
	$validPermalink = preg_match($httpLinkExpr, $item['guid']);
	if (preg_match($httpLinkExpr, $item['link']) ) {
	if (!$validPermalink) {
	$item['guid'] = $item['link'];
	}
	} elseif ($validPermalink) {
	$item['link'] = $item['guid'];
	}
	$link = $item['link'];
	if (!empty($link)) {
	$this->items[$link] = $item;
	}

Either the matching for valid <link> values should improve or <link> should never be replaced by <guid> (as before).

@boomboxnation Thanks for reporting this. What is the link that isn't working?

[boomboxnation]

Something in my torrent IDs isn't matching then:

https://www.BLARGH.net/tor/download.php/7W0pSLI4asiHLzxtEm83RzUKmn8yM6cjUuQGwdG5rrnXZjjibq,,yt6jo7Db+LBNBHXZ,6+tx9iGxqY,j,beUD9oJO,Ej4+yt+N8g6xJxxbF2ji9riA++libga39A7d6KuWJfsPKAnfAeqk3oylBjr8EuJqmSzfrJ6Va0GqtjMCMsSBj87bayo4=

This makes sense as like 3 out of 100 did load properly. Here is the URL for one I think loaded properly:

https://www.BLARGH.net/tor/download.php/qCc7UKnOT0nQIE+MfYeVO9zfJfe2++xYUTAq0IyMELTwB2iICoeH5hx9pwQwQPOvgGDp1,C9Ydv7ms12y0ai7BEpnFQbSPWgrgwC7CC+Q78lvU840bk2gMl3e94MqLVdN3UFbhADX5BDIEexzxZbgEzwYSfovbVX9plLCDPeP0WclkKKAao9umQ=

Entire <item> section for a non-loading one...

<item>
<guid>https://www.BLARGH.net/t/928108</guid>
<title>Just another linux iso</title>
<link>https://www.BLARGH.net/tor/download.php/7W0pSLI4asiHLzxtEm83RzUKmn8yM6cjUuQGwdG5rrnXZjjibq,,yt6jo7Db+LBNBHXZ,6+tx9iGxqY,j,beUD9oJO,Ej4+yt+N8g6xJxxbF2ji9riA++libga39A7d6KuWJfsPKAnfAeqk3oylBjr8EuJqmSzfrJ6Va0GqtjMCMsSBj87bayo4=</link>
<category>LINUX ISO</category>
<description>A single script to build a minimal live Linux operating system from source code that runs Doom on boot. <br/></description>
<pubDate>Sun, 30 Apr 2023 12:36:28 +0000</pubDate>
</item>

[stickz]

While the new commit does now let me add new RSS and update existing, it is trying to load the <guid> rather than the <link> from the feed's <item> section, which in my case fails to load.

@boomboxnation Please create a new issue report to further discuss this separate issue with @TrimmingFool. We need to close this one off and reference a new issue report when a fix is created.

We want to be able to say: This issue was fixed in v4.1.x. Then document changes, so people know which version to use. Developers need to reference the detailed issue report as well, in-case we accidentally introduce a bug trying to fix a problem.