Issue #3303538 by DamienMcKenna: Channel image link is empty.

CHANGELOG.txt

@@ -4,6 +4,7 @@ Advanced Views RSS Feed 8.x-2.x, 2023-xx-xx
   available on the filesystem.
 #3383734 by DamienMcKenna, idebr: Warning: filesize(): stat failed for [image
   url] when using a static image as the feed thumbnail.
+#3303538 by DamienMcKenna: Channel image link is empty.
 
 
 Advanced Views RSS Feed 8.x-2.1, 2023-07-11

README.md

@@ -33,6 +33,26 @@ feeds.
 * Review the output and continue making changes as necessary.
 
 
+## Troubleshooting
+
+### The channel image link tag is incorrect
+
+If the channel->image->link tag outputs as `imagelink` instead of just `link`,
+the problem is that the module's custom `views-view-rss.html.twig` file is not
+being used. To fix this, either copy that file to the theme's "templates"
+directory, or update the theme's twig file to match the following:
+
+    {{ channel_elements|render|replace({"imagelink": "link"})|raw }}
+
+This is safe to do as the content passes through Drupal's render system first,
+which will filter out any security concerns.
+
+
+### RSS validators complain of an invalid "imagelink" tag
+
+See "The channel image link tag is incorrect" above.
+
+
 ## Support
 
 Please post questions, bug reports and feature reports to the [project's issue

modules/views_rss_core/views_rss_core.inc

@@ -118,10 +118,19 @@ function views_rss_core_preprocess_channel_image(&$variables) {
   }
 
   // The image's link element identifies the URL of the web site represented by
-  // the image, not the feed URL.
+  // the image, not the feed URL. The first problem is that Drupal's normal Twig
+  // filtering strips out LINK tag values as it is supposed to be a self-closing
+  // tag, e.g. "<link src="something" />" and not "<link>something</link>". The
+  // second problem is that LINK tags are also normally filtered out entirely
+  // because a LINK tag is normally considered a security problem. Therefore,
+  // output the tag with a custom tag name that is then adjusted in the template
+  // file. Yes, this is super hacky, but there aren't too many ways around it.
+  // @see \Drupal\Core\Render\Element\HtmlTag::$voidElements
+  // @see \Drupal\Core\Render\Renderer::xssFilterAdminIfUnsafe()
+  // @see views-view-rss.html.twig
   $variables['elements'][0]['value']['link'] = [
     '#type' => 'html_tag',
-    '#tag' => 'link',
+    '#tag' => 'imagelink',
     '#value' => views_rss_link_to_front_page(),
   ];
 

templates/views-view-rss.html.twig

+{#
+/**
+ * @file
+ * Default template for feed displays that use the RSS style.
+ *
+ * Available variables:
+ * - link: The link to the feed (the view path).
+ * - namespaces: The XML namespaces (added automatically).
+ * - title: The title of the feed (as set in the view).
+ * - description: The feed description (from feed settings).
+ * - langcode: The language encoding.
+ * - channel_elements: The formatted channel elements.
+ * - items: The feed items themselves.
+ *
+ * @see template_preprocess_views_view_rss()
+ *
+ * @ingroup themeable
+ */
+#}
+<?xml version="1.0" encoding="utf-8"?>
+<rss version="2.0" xml:base="{{ link }}"{{ namespaces }}>
+  <channel>
+    <title>{{ title }}</title>
+    <link>{{ link }}</link>
+    <description>{{ description }}</description>
+    <language>{{ langcode }}</language>
+    {##
+     # Output the channel elements as a raw tag so that the included HTML tags
+     # are not converted to HTML entities. Also rename the "imagelink" tag to
+     # just "link" to avoid it being filtered out by Drupal's normal rendering
+     # system. This is safe to do as any security concerns are taken care of
+     # by the render function.
+     #}
+    {{ channel_elements|render|replace({"imagelink": "link"})|raw }}
+    {{ items }}
+  </channel>
+</rss>

tests/src/Functional/DisplayFeedTest.php

@@ -189,8 +189,7 @@ class DisplayFeedTest extends BrowserTestBase {
     // $this->assertEquals($site_image_url, $driver->getText('//rss/channel/image/url'));
     $this->assertEquals('https://www.drupal.org/misc/druplicon.png', $driver->getText('//rss/channel/image/url'));
     $this->assertEquals('Test feed', $driver->getText('//rss/channel/image/title'));
-    // @todo This should be the main site URL.
-    // $this->assertEquals('', $driver->getText('//rss/channel/image/link'));
+    $this->assertEquals($front_page, $driver->getText('//rss/channel/image/link'));
     // @todo Work out a better approach for this.
     // $this->assertEquals('', $driver->getText('//rss/channel/image/width'));
     // $this->assertEquals('', $driver->getText('//rss/channel/image/height'));

views_rss.module

@@ -169,10 +169,15 @@ function views_rss_map_assoc($array) {
  * Implemenents hook_theme_registry_alter().
  */
 function views_rss_theme_registry_alter(array &$registry) {
+  $module_dir = \Drupal::service('extension.list.module')->getPath('views_rss');
+
   // Use the twig file that comes with this module so that the CDATA wrapper can
   // be added.
-  $module_dir = \Drupal::service('extension.list.module')->getPath('views_rss');
   $registry['views_view_row_rss']['path'] = $module_dir . '/templates';
+
+  // Use the custom twig file for the main RSS output to work around problems
+  // outputting a LINK tag in Twig.
+  $registry['views_view_rss']['path'] = $module_dir . '/templates';
 }
 
 /**