MDL-81144 core: Convert before_http_headers

lib/classes/hook/output/before_http_headers.php

@@ -0,0 +1,54 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core\hook\output;
+
+/**
+ * Class before_http_headers
+ *
+ * @package    core
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @property-read \renderer_base $renderer The page renderer object
+ */
+#[\core\attribute\tags('output')]
+#[\core\attribute\label('Allows plugins to make changes before headers are sent')]
+#[\core\attribute\hook\replaces_callbacks('before_http_headers')]
+class before_http_headers {
+    /**
+     * Hook to allow subscribers to modify the process before headers are sent.
+     *
+     * @param \renderer_base $renderer
+     */
+    public function __construct(
+        /** @var \renderer_base The page renderer object */
+        public readonly \renderer_base $renderer,
+    ) {
+    }
+
+
+    /**
+     * Process legacy callbacks.
+     */
+    public function process_legacy_callbacks(): void {
+        $pluginswithfunction = get_plugins_with_function(function: 'before_http_headers', migratedtohook: true);
+        foreach ($pluginswithfunction as $plugins) {
+            foreach ($plugins as $function) {
+                $function();
+            }
+        }
+    }
+}

lib/outputrenderers.php

@@ -40,6 +40,7 @@
 use core\hook\output\after_standard_main_region_html_generation;
 use core\hook\output\before_footer_html_generation;
 use core\hook\output\before_html_attributes;
+use core\hook\output\before_http_headers;
 use core\hook\output\before_standard_footer_html_generation;
 use core\hook\output\before_standard_top_of_body_html_generation;
 use core\output\named_templatable;
@@ -1359,14 +1360,12 @@ public function redirect_message($encodedurl, $message, $delay, $debugdisablered
     public function header() {
         global $USER, $CFG, $SESSION;
 
-        // Give plugins an opportunity touch things before the http headers are sent
-        // such as adding additional headers. The return value is ignored.
-        $pluginswithfunction = get_plugins_with_function('before_http_headers', 'lib.php');
-        foreach ($pluginswithfunction as $plugins) {
-            foreach ($plugins as $function) {
-                $function();
-            }
-        }
+        // Ensure that the callback exists prior to cache purge.
+        // This is a critical page path.
+        // TODO MDL-81134 Remove after LTS+1.
+        require_once(__DIR__ . '/classes/hook/output/before_http_headers.php');
+
+        di::get(hook_manager::class)->dispatch(new before_http_headers($this));
 
         if (\core\session\manager::is_loggedinas()) {
             $this->page->add_body_class('userloggedinas');

lib/upgrade.txt

@@ -39,14 +39,11 @@ information provided here is intended especially for developers.
 * The following callbacks have been migrated to hooks:
   - before_standard_html_head() -> core\hook\output\before_standard_head_html_generation
   - bulk_user_actions() -> core_user\hook\extend_bulk_user_actions
+  - before_http_headers() -> core\hook\output\before_http_headers
   - before_standard_top_of_body_html() -> core\hook\output\before_standard_top_of_body_html_generation
   - standard_after_main_region_html() -> core\hook\output\after_standard_main_region_html_generation
-<<<<<<< HEAD
-  - standard_footer_html() -> core\hook\output\before_standard_footer_html_generation
-=======
   - before_footer() -> core\hook\output\before_footer_html_generation
   - standard_footer_html() -> core\hook\output\before_standard_footer_html_generation
->>>>>>> 3516753f3a (MDL-81144 core: Convert before_footer to hook)
   - add_htmlattributes() -> core\hook\output\before_html_attributes
 * Deprecated PARAM_ types with the exception of PARAM_CLEAN now emit a deprecation exception. These were all deprecated in Moodle 2.0.
 * A new \core\attribute\deprecated attribute can be used to more clearly describe deprecated methods.