Merge pull request #4236 from Automattic/fix/structure-ordering-cache

Fix structure ordering cache

includes/class-sensei-admin.php

@@ -1581,7 +1581,7 @@ public function save_lesson_order( $order_string = '', $course_id = 0 ) {
 	}
 
 	/**
-	 * Get course structure.
+	 * Get or filter course structure for lesson ordering.
 	 *
 	 * @param int|array   $course_structure Structure array or course ID to get the structure.
 	 * @param null|string $type             Optional type to filter the content.
@@ -1591,7 +1591,7 @@ public function save_lesson_order( $order_string = '', $course_id = 0 ) {
 	private function get_course_structure( $course_structure = null, $type = null ) {
 		$course_structure = is_array( $course_structure )
 			? $course_structure
-			: Sensei_Course_Structure::instance( $course_structure )->get( 'edit' );
+			: Sensei_Course_Structure::instance( $course_structure )->get( 'edit', wp_using_ext_object_cache() );
 
 		if ( isset( $type ) ) {
 			$course_structure = array_filter(

includes/class-sensei-course-structure.php

@@ -61,7 +61,8 @@ private function __construct( int $course_id ) {
 	 * @see Sensei_Course_Structure::prepare_lesson()
 	 * @see Sensei_Course_Structure::prepare_module()
 	 *
-	 * @param string $context Context that structure is being retrieved for. Possible values: edit, view.
+	 * @param string  $context  Context that structure is being retrieved for. Possible values: edit, view.
+	 * @param boolean $no_cache Avoid query cache.
 	 *
 	 * @return array {
 	 *     An array which has course structure information.
@@ -70,7 +71,11 @@ private function __construct( int $course_id ) {
 	 *                 and prepare_module().
 	 * }
 	 */
-	public function get( $context = 'view' ) {
+	public function get( $context = 'view', $no_cache = false ) {
+		if ( $no_cache ) {
+			add_filter( 'posts_where', [ $this, 'filter_no_cache_where' ] );
+		}
+
 		$context = in_array( $context, [ 'view', 'edit' ], true ) ? $context : 'view';
 
 		$structure = [];
@@ -97,9 +102,28 @@ public function get( $context = 'view' ) {
 			$structure[] = $this->prepare_lesson( $lesson );
 		}
 
+		if ( $no_cache ) {
+			remove_filter( 'posts_where', [ $this, 'filter_no_cache_where' ] );
+		}
+
 		return $structure;
 	}
 
+	/**
+	 * Filter where adding an extra condition to avoid cache.
+	 *
+	 * @access private
+	 *
+	 * @param string $where Current where.
+	 *
+	 * @return string Where with extra condition to avoid cache.
+	 */
+	public function filter_no_cache_where( $where ) {
+		$time = time();
+
+		return $where . ' AND ' . $time . ' = ' . $time;
+	}
+
 	/**
 	 * Prepare the result for a module.
 	 *

includes/rest-api/class-sensei-rest-api-course-structure-controller.php

@@ -189,7 +189,7 @@ public function save_course_structure( WP_REST_Request $request ) {
 		}
 
 		$response = new WP_REST_Response();
-		$response->set_data( $course_structure->get( 'edit' ) );
+		$response->set_data( $course_structure->get( 'edit', wp_using_ext_object_cache() ) );
 
 		return $response;
 	}