schedule migration because it takes quite some time

activitypub.php

@@ -35,7 +35,6 @@ function init() {
 	require_once \dirname( __FILE__ ) . '/includes/class-http.php';
 	require_once \dirname( __FILE__ ) . '/includes/class-signature.php';
 	require_once \dirname( __FILE__ ) . '/includes/class-webfinger.php';
-	require_once \dirname( __FILE__ ) . '/includes/class-migration.php';
 	require_once \dirname( __FILE__ ) . '/includes/peer/class-followers.php';
 	require_once \dirname( __FILE__ ) . '/includes/functions.php';
 
@@ -43,6 +42,9 @@ function init() {
 	require_once \dirname( __FILE__ ) . '/includes/model/class-post.php';
 	require_once \dirname( __FILE__ ) . '/includes/model/class-follower.php';
 
+	require_once \dirname( __FILE__ ) . '/includes/class-migration.php';
+	Migration::init();
+
 	require_once \dirname( __FILE__ ) . '/includes/class-activity-dispatcher.php';
 	Activity_Dispatcher::init();
 

includes/class-activity-dispatcher.php

@@ -61,6 +61,9 @@ class Activity_Dispatcher {
 	 * @return void
 	 */
 	public static function send_activity( Post $activitypub_post, $activity_type ) {
+		// check if a migration is needed before sending new posts
+		\Activitypub\Migration::maybe_migrate();
+
 		// get latest version of post
 		$user_id = $activitypub_post->get_post_author();
 

includes/class-admin.php

@@ -13,6 +13,7 @@ class Admin {
 	public static function init() {
 		\add_action( 'admin_menu', array( self::class, 'admin_menu' ) );
 		\add_action( 'admin_init', array( self::class, 'register_settings' ) );
+		\add_action( 'admin_init', array( self::class, 'schedule_migration' ) );
 		\add_action( 'show_user_profile', array( self::class, 'add_profile' ) );
 		\add_action( 'admin_enqueue_scripts', array( self::class, 'enqueue_scripts' ) );
 	}
@@ -144,6 +145,12 @@ class Admin {
 		);
 	}
 
+	public static function schedule_migration() {
+		if ( ! \wp_next_scheduled( 'activitypub_schedule_migration' ) ) {
+			\wp_schedule_single_event( \time(), 'activitypub_schedule_migration' );
+		}
+	}
+
 	public static function add_settings_help_tab() {
 		require_once \dirname( __FILE__ ) . '/help.php';
 	}

includes/class-migration.php

@@ -9,6 +9,10 @@ class Migration {
 	 */
 	private static $target_version = '1.0.0';
 
+	public static function init() {
+		\add_action( 'activitypub_schedule_migration', array( self::class, 'maybe_migrate' ) );
+	}
+
 	public static function get_target_version() {
 		return self::$target_version;
 	}