Add singleton-based plugin loading mechanism

README.md

@@ -5,7 +5,7 @@
 - Tags: nodeinfo, fediverse, ostatus, diaspora, activitypub
 - Requires at least: 6.6
 - Tested up to: 6.9
-- Stable tag: 3.0.0
+- Stable tag: 3.1.0
 - Requires PHP: 7.2
 - License: MIT
 - License URI: https://opensource.org/licenses/MIT
@@ -81,6 +81,11 @@ If either check fails, you'll see recommendations on how to fix the issue.
 
 Project and support maintained on github at [pfefferle/wordpress-nodeinfo](https://github.com/pfefferle/wordpress-nodeinfo).
 
+### 3.1.0
+
+* Added singleton-based plugin loading mechanism for better extensibility
+* Added backwards compatibility handler for deprecated `wellknown_nodeinfo_data` filter
+
 ### 3.0.0
 
 * Refactored to filter-based architecture for better extensibility

includes/class-nodeinfo.php

@@ -0,0 +1,183 @@
+<?php
+/**
+ * Nodeinfo Class
+ *
+ * @package Nodeinfo
+ */
+
+namespace Nodeinfo;
+
+use Nodeinfo\Controller\Nodeinfo as Controller_Nodeinfo;
+use Nodeinfo\Controller\Nodeinfo2 as Controller_Nodeinfo2;
+use Nodeinfo\Integration\Nodeinfo10;
+use Nodeinfo\Integration\Nodeinfo11;
+use Nodeinfo\Integration\Nodeinfo20;
+use Nodeinfo\Integration\Nodeinfo21;
+use Nodeinfo\Integration\Nodeinfo22;
+
+/**
+ * Nodeinfo Class
+ *
+ * @package Nodeinfo
+ */
+class Nodeinfo {
+	/**
+	 * Instance of the class.
+	 *
+	 * @var Nodeinfo
+	 */
+	private static $instance;
+
+	/**
+	 * Whether the class has been initialized.
+	 *
+	 * @var boolean
+	 */
+	private $initialized = false;
+
+	/**
+	 * Get the instance of the class.
+	 *
+	 * @return Nodeinfo
+	 */
+	public static function get_instance() {
+		if ( null === self::$instance ) {
+			self::$instance = new self();
+		}
+
+		return self::$instance;
+	}
+
+	/**
+	 * Do not allow multiple instances of the class.
+	 */
+	private function __construct() {
+		// Do nothing.
+	}
+
+	/**
+	 * Initialize the plugin.
+	 */
+	public function init() {
+		if ( $this->initialized ) {
+			return;
+		}
+
+		$this->register_integrations();
+		$this->register_hooks();
+
+		if ( \is_admin() ) {
+			$this->register_admin_hooks();
+		}
+
+		$this->initialized = true;
+	}
+
+	/**
+	 * Register NodeInfo version integrations.
+	 *
+	 * These only register filters, so they can be called directly.
+	 */
+	public function register_integrations() {
+		Nodeinfo10::init();
+		Nodeinfo11::init();
+		Nodeinfo20::init();
+		Nodeinfo21::init();
+		Nodeinfo22::init();
+	}
+
+	/**
+	 * Register hooks.
+	 */
+	public function register_hooks() {
+		// Register REST routes.
+		\add_action( 'rest_api_init', array( $this, 'register_routes' ) );
+
+		// Add WebFinger and Host-Meta discovery.
+		\add_filter( 'webfinger_user_data', array( Controller_Nodeinfo::class, 'jrd' ), 10, 3 );
+		\add_filter( 'webfinger_post_data', array( Controller_Nodeinfo::class, 'jrd' ), 10, 3 );
+		\add_filter( 'host_meta', array( Controller_Nodeinfo::class, 'jrd' ) );
+
+		// Add rewrite rules for well-known endpoints (only during flush).
+		\add_filter( 'rewrite_rules_array', array( $this, 'add_rewrite_rules' ) );
+
+		// Register deprecated filter handlers.
+		\add_filter( 'nodeinfo_discovery', array( $this, 'deprecated_wellknown_nodeinfo_data' ), 99 );
+	}
+
+	/**
+	 * Handles the deprecated wellknown_nodeinfo_data filter.
+	 *
+	 * @param array $discovery The discovery document.
+	 * @return array The filtered discovery document.
+	 */
+	public function deprecated_wellknown_nodeinfo_data( $discovery ) {
+		/**
+		 * Filters the NodeInfo discovery document.
+		 *
+		 * @deprecated 3.0.0 Use nodeinfo_discovery instead.
+		 *
+		 * @param array $discovery The discovery document.
+		 */
+		return \apply_filters_deprecated(
+			'wellknown_nodeinfo_data',
+			array( $discovery ),
+			'3.0.0',
+			'nodeinfo_discovery'
+		);
+	}
+
+	/**
+	 * Register admin hooks.
+	 */
+	public function register_admin_hooks() {
+		// Initialize Site Health checks.
+		\add_action( 'admin_init', array( Health_Check::class, 'init' ) );
+	}
+
+	/**
+	 * Register REST API routes.
+	 */
+	public function register_routes() {
+		$nodeinfo_controller = new Controller_Nodeinfo();
+		$nodeinfo_controller->register_routes();
+
+		$nodeinfo2_controller = new Controller_Nodeinfo2();
+		$nodeinfo2_controller->register_routes();
+	}
+
+	/**
+	 * Add rewrite rules for well-known endpoints.
+	 *
+	 * @param array $rules The existing rewrite rules.
+	 * @return array The modified rewrite rules.
+	 */
+	public function add_rewrite_rules( $rules ) {
+		$new_rules = array(
+			'^.well-known/nodeinfo'    => 'index.php?rest_route=/nodeinfo/discovery',
+			'^.well-known/x-nodeinfo2' => 'index.php?rest_route=/nodeinfo2/1.0',
+		);
+
+		return \array_merge( $new_rules, $rules );
+	}
+
+	/**
+	 * Handle plugin activation.
+	 *
+	 * Initializes the plugin and flushes rewrite rules. The rewrite_rules_array
+	 * filter will add our rules during the flush.
+	 */
+	public static function activate() {
+		self::get_instance()->init();
+		\flush_rewrite_rules();
+	}
+
+	/**
+	 * Handle plugin deactivation.
+	 *
+	 * Should be called on plugin deactivation.
+	 */
+	public static function deactivate() {
+		\flush_rewrite_rules();
+	}
+}

nodeinfo.php

@@ -3,13 +3,12 @@
  * Plugin Name: NodeInfo
  * Plugin URI: https://github.com/pfefferle/wordpress-nodeinfo/
  * Description: NodeInfo is an effort to create a standardized way of exposing metadata about a server running one of the distributed social networks.
- * Version: 3.0.0
+ * Version: 3.1.0
  * Author: Matthias Pfefferle
  * Author URI: https://notiz.blog/
  * License: MIT
  * License URI: http://opensource.org/licenses/MIT
  * Text Domain: nodeinfo
- * Domain Path: /languages
  *
  * @package Nodeinfo
  */
@@ -32,65 +31,22 @@
 require_once NODEINFO_PLUGIN_DIR . 'includes/class-nodeinfo-endpoint.php';
 
 /**
- * Initialize the plugin.
- */
-function nodeinfo_init() {
-	// Initialize NodeInfo version integrations.
-	Nodeinfo\Integration\Nodeinfo10::init();
-	Nodeinfo\Integration\Nodeinfo11::init();
-	Nodeinfo\Integration\Nodeinfo20::init();
-	Nodeinfo\Integration\Nodeinfo21::init();
-	Nodeinfo\Integration\Nodeinfo22::init();
-
-	// Register REST routes.
-	add_action( 'rest_api_init', 'nodeinfo_register_routes' );
-
-	// Add WebFinger and Host-Meta discovery.
-	add_filter( 'webfinger_user_data', array( Nodeinfo\Controller\Nodeinfo::class, 'jrd' ), 10, 3 );
-	add_filter( 'webfinger_post_data', array( Nodeinfo\Controller\Nodeinfo::class, 'jrd' ), 10, 3 );
-	add_filter( 'host_meta', array( Nodeinfo\Controller\Nodeinfo::class, 'jrd' ) );
-}
-add_action( 'init', 'nodeinfo_init', 9 );
-
-/**
- * Initialize admin-only features.
- */
-function nodeinfo_admin_init() {
-	// Initialize Site Health checks.
-	Nodeinfo\Health_Check::init();
-}
-add_action( 'admin_init', 'nodeinfo_admin_init' );
-
-/**
- * Register REST API routes.
- */
-function nodeinfo_register_routes() {
-	$nodeinfo_controller = new Nodeinfo\Controller\Nodeinfo();
-	$nodeinfo_controller->register_routes();
-
-	$nodeinfo2_controller = new Nodeinfo\Controller\Nodeinfo2();
-	$nodeinfo2_controller->register_routes();
-}
-
-/**
- * Add rewrite rules for well-known endpoints.
- */
-function nodeinfo_add_rewrite_rules() {
-	add_rewrite_rule( '^.well-known/nodeinfo', 'index.php?rest_route=/nodeinfo/discovery', 'top' );
-	add_rewrite_rule( '^.well-known/x-nodeinfo2', 'index.php?rest_route=/nodeinfo2/1.0', 'top' );
-}
-add_action( 'init', 'nodeinfo_add_rewrite_rules', 1 );
-
-/**
- * Flush rewrite rules on activation.
+ * Plugin initialization function.
+ *
+ * @return Nodeinfo\Nodeinfo The plugin instance.
  */
-function nodeinfo_activate() {
-	nodeinfo_add_rewrite_rules();
-	flush_rewrite_rules();
+function nodeinfo_plugin() {
+	return Nodeinfo\Nodeinfo::get_instance();
 }
-register_activation_hook( __FILE__, 'nodeinfo_activate' );
 
-/**
- * Flush rewrite rules on deactivation.
- */
-register_deactivation_hook( __FILE__, 'flush_rewrite_rules' );
+// Initialize the plugin after all plugins are loaded.
+add_action(
+	'plugins_loaded',
+	function () {
+		nodeinfo_plugin()->init();
+	}
+);
+
+// Register activation and deactivation hooks.
+register_activation_hook( __FILE__, array( Nodeinfo\Nodeinfo::class, 'activate' ) );
+register_deactivation_hook( __FILE__, array( Nodeinfo\Nodeinfo::class, 'deactivate' ) );