Save Navigation Block data to a wp_navigation post type

lib/navigation.php

@@ -384,3 +384,54 @@ function gutenberg_add_block_menu_item_styles_to_nav_menus( $hook ) {
 	}
 }
 add_action( 'admin_enqueue_scripts', 'gutenberg_add_block_menu_item_styles_to_nav_menus' );
+
+
+/**
+ * Registers block editor 'wp_navigation' post type.
+ */
+function gutenberg_register_navigation_post_type() {
+	$labels = array(
+		'name'                  => __( 'Navigation Menus', 'gutenberg' ),
+		'singular_name'         => __( 'Navigation Menu', 'gutenberg' ),
+		'menu_name'             => _x( 'Navigation Menus', 'Admin Menu text', 'gutenberg' ),
+		'add_new'               => _x( 'Add New', 'Navigation Menu', 'gutenberg' ),
+		'add_new_item'          => __( 'Add New Navigation Menu', 'gutenberg' ),
+		'new_item'              => __( 'New Navigation Menu', 'gutenberg' ),
+		'edit_item'             => __( 'Edit Navigation Menu', 'gutenberg' ),
+		'view_item'             => __( 'View Navigation Menu', 'gutenberg' ),
+		'all_items'             => __( 'All Navigation Menus', 'gutenberg' ),
+		'search_items'          => __( 'Search Navigation Menus', 'gutenberg' ),
+		'parent_item_colon'     => __( 'Parent Navigation Menu:', 'gutenberg' ),
+		'not_found'             => __( 'No Navigation Menu found.', 'gutenberg' ),
+		'not_found_in_trash'    => __( 'No Navigation Menu found in Trash.', 'gutenberg' ),
+		'archives'              => __( 'Navigation Menu archives', 'gutenberg' ),
+		'insert_into_item'      => __( 'Insert into Navigation Menu', 'gutenberg' ),
+		'uploaded_to_this_item' => __( 'Uploaded to this Navigation Menu', 'gutenberg' ),
+		// Some of these are a bit weird, what are they for?
+		'filter_items_list'     => __( 'Filter Navigation Menu list', 'gutenberg' ),
+		'items_list_navigation' => __( 'Navigation Menus list navigation', 'gutenberg' ),
+		'items_list'            => __( 'Navigation Menus list', 'gutenberg' ),
+	);
+
+	$args = array(
+		'labels'                => $labels,
+		'description'           => __( 'Navigation menus.', 'gutenberg' ),
+		'public'                => false,
+		'has_archive'           => false,
+		'show_ui'               => false,
+		'show_in_menu'          => 'themes.php',
+		'show_in_admin_bar'     => false,
+		'show_in_rest'          => true,
+		'map_meta_cap'          => true,
+		'rest_base'             => 'navigation',
+		'rest_controller_class' => 'WP_REST_Posts_Controller',
+		'supports'              => array(
+			'title',
+			'editor',
+			'revisions',
+		),
+	);
+
+	register_post_type( 'wp_navigation', $args );
+}
+add_action( 'init', 'gutenberg_register_navigation_post_type' );

packages/block-library/src/navigation/block.json

@@ -11,6 +11,9 @@
 	],
 	"textdomain": "default",
 	"attributes": {
+		"navigationMenuId": {
+			"type": "number"
+		},
 		"orientation": {
 			"type": "string",
 			"default": "horizontal"