MDL-78294 core_tag: New 'viewurl' property in tag_item_exporter

New additional property 'viewurl' has been added to the pre-defined
structure in tag_item_exporter. This property represents the URL to
view a given tag.

tag/classes/external/tag_item_exporter.php

@@ -27,6 +27,7 @@
 defined('MOODLE_INTERNAL') || die();
 
 use core\external\exporter;
+use renderer_base;
 
 /**
  * Contains related class for displaying information of a tag item.
@@ -89,4 +90,33 @@ protected static function define_properties() {
             ],
         ];
     }
+
+    /**
+     * Return the list of additional properties used only for display.
+     *
+     * @return array
+     */
+    protected static function define_other_properties() {
+        return [
+            'viewurl' => [
+                'type' => PARAM_URL,
+                'description' => 'The url to view the tag.',
+                'optional' => true,
+                'default' => null,
+                'null' => NULL_ALLOWED,
+            ],
+        ];
+    }
+
+    /**
+     * Get the additional values to inject while exporting.
+     *
+     * @param renderer_base $output The renderer.
+     * @return array Keys are the property names, values are their values.
+     */
+    protected function get_other_values(renderer_base $output) {
+        return [
+            'viewurl' => \core_tag_tag::make_url($this->data->tagcollid, $this->data->rawname)->out(false),
+        ];
+    }
 }

tag/upgrade.txt

@@ -1,6 +1,11 @@
 This files describes API changes in tagging, information provided
 here is intended especially for developers.
 
+=== 4.4 ===
+
+* New additional property 'viewurl' has been added to the pre-defined structure in tag_item_exporter. This property
+  represents the URL to view a given tag.
+
 === 3.6 ===
 
 * The following functions have been finally deprecated and can not be used anymore: