Improve Nav block loading UX by preloading Navigation menu requests (#…

…48683)

* Scaffold out preloading

* All GET and OPTIONS preloading

* Make preload paths more readable via add_query_arg

* Add comment to unusual usage

* Resolve PHPCS

* Fix formatting

* Rename away from “permissions”

* Limit to Site Editor

* Add context to doc block

* Preload Browse Mode sidebar Navigation

* Remove redundant preload

* Use int not string for numeric

lib/compat/wordpress-6.3/navigation-block-preloading.php

@@ -0,0 +1,63 @@
+<?php
+/**
+ * Patches resources loaded by the block editor page
+ * to include Navigation posts.
+ *
+ * @package gutenberg
+ */
+
+/**
+ * Preloads requests needed for Navigation posts
+ *
+ * @param array                   $preload_paths    Preload paths to be filtered.
+ * @param WP_Block_Editor_Context $context          The current block editor context.
+ * @return array
+ */
+function gutenberg_preload_navigation_posts( $preload_paths, $context ) {
+
+	// Limit to the Site Editor.
+	if ( ! empty( $context->name ) && 'core/edit-site' !== $context->name ) {
+		return $preload_paths;
+	}
+
+	$navigation_rest_route = rest_get_route_for_post_type_items(
+		'wp_navigation'
+	);
+
+	// Preload the OPTIONS request for all Navigation posts request.
+	$preload_paths[] = array( $navigation_rest_route, 'OPTIONS' );
+
+	// Preload the GET request for ALL 'published' or 'draft' Navigation posts.
+	$preload_paths[] = array(
+		add_query_arg(
+			array(
+				'context'   => 'edit',
+				'per_page'  => 100,
+				'_locale'   => 'user',
+				// array indices are required to avoid query being encoded and not matching in cache.
+				'status[0]' => 'publish',
+				'status[1]' => 'draft',
+			),
+			$navigation_rest_route
+		),
+		'GET',
+	);
+
+	// Preload request for Browse Mode sidebar "Navigation" section.
+	$preload_paths[] = array(
+		add_query_arg(
+			array(
+				'context'  => 'edit',
+				'per_page' => 1,
+				'status'   => 'publish',
+				'order'    => 'desc',
+				'orderby'  => 'date',
+			),
+			$navigation_rest_route
+		),
+		'GET',
+	);
+
+	return $preload_paths;
+}
+add_filter( 'block_editor_rest_api_preload_paths', 'gutenberg_preload_navigation_posts', 10, 2 );

lib/load.php

@@ -49,6 +49,7 @@ function gutenberg_is_experiment_enabled( $name ) {
 	require_once __DIR__ . '/compat/wordpress-6.3/class-gutenberg-rest-global-styles-controller-6-3.php';
 	require_once __DIR__ . '/compat/wordpress-6.3/rest-api.php';
 	require_once __DIR__ . '/compat/wordpress-6.3/theme-previews.php';
+	require_once __DIR__ . '/compat/wordpress-6.3/navigation-block-preloading.php';
 
 	// Experimental.
 	if ( ! class_exists( 'WP_Rest_Customizer_Nonces' ) ) {