feat: Add garbage collection cleanup admin and cron job

src/Admin/Settings.php

@@ -102,6 +102,49 @@ function () {
 					]
 				);
 
+				register_graphql_settings_field(
+					'graphql_persisted_queries_section',
+					[
+						'name'              => 'garbage_collection_toggle',
+						'label'             => __( 'Clean Up Queries', 'wp-graphql-smart-cache' ),
+						'desc'              => __( 'Toggle on to enable garbage collection of saved queries older than number of days specified below', 'wp-graphql-smart-cache' ),
+						'type'              => 'checkbox',
+						'default'           => 'off',
+						'sanitize_callback' => function ( $value ) {
+							/**
+							 * When enable garbage collection,
+							 * schedule the garbage collection action/event to run once daily.
+							 * Otherwise remove it.
+							 */
+							if ( 'on' === $value ) {
+								if ( ! wp_next_scheduled( 'wp_graphql_smart_cache_query_cleanup' ) ) {
+									// Add scheduled job to run in one minute
+									wp_schedule_event( time() + 60, 'daily', 'wp_graphql_smart_cache_query_cleanup' );
+								}
+							} else {
+								wp_clear_scheduled_hook( 'wp_graphql_smart_cache_query_cleanup' );
+							}
+							return $value;
+						},
+					]
+				);
+
+				register_graphql_settings_field(
+					'graphql_persisted_queries_section',
+					[
+						'name'              => 'garbage_collection_age',
+						'desc'              => __( 'Age, in number of days, of saved query when it will be removed', 'wp-graphql-smart-cache' ),
+						'type'              => 'number',
+						'default'           => '30',
+						'sanitize_callback' => function ( $value ) {
+							if ( 1 > $value || ! is_numeric( $value ) ) {
+								return null;
+							}
+							return (int) $value;
+						},
+					]
+				);
+
 				// Add a tab section to the graphql admin settings page
 				register_graphql_settings_section(
 					'graphql_cache_section',

src/Utils.php

@@ -43,6 +43,30 @@ public static function getPostByTermName( $query_id, $type, $taxonomy ) {
 		return $post;
 	}
 
+	/**
+	 * @param integer $days_ago  Posts older than this many days ago will be deleted.
+	 *
+	 * @return [WP_Post]
+	 */
+	public static function getDocumentsBeforeDays( $days_ago = 30 ) {
+		$wp_query = new \WP_Query(
+			[
+				'post_type'      => Document::TYPE_NAME,
+				'post_status'    => 'publish',
+				'posts_per_page' => -1,
+				'fields'         => 'ids',
+				'date_query'     => [
+					[
+						'column' => 'post_modified_gmt',
+						'before' => $days_ago . ' days ago',
+					],
+				],
+			]
+		);
+
+		return $wp_query->get_posts();
+	}
+
 	/**
 	 * Generate query hash for graphql query string
 	 *

wp-graphql-smart-cache.php

@@ -273,3 +273,29 @@ function appsero_init_tracker_wpgraphql_smart_cache() {
 }
 
 appsero_init_tracker_wpgraphql_smart_cache();
+
+/**
+ * When the garbage collection event runs daily, cleanup aged out jobs.
+ */
+add_action( 'wp_graphql_smart_cache_query_cleanup', function() {
+	// Check that the clean up toggle is still enabled.
+	$garbage_toggle = get_graphql_setting( 'garbage_collection_toggle', null, 'graphql_persisted_queries_section' );
+
+	// Only run the event when the toggle is enabled.
+	if ( 'on' !== $garbage_toggle ) {
+		// Remove the scheduled cron job from firing again if the toggle is not on.
+		wp_clear_scheduled_hook( 'wp_graphql_smart_cache_query_cleanup' );
+		return;
+	}
+
+	$age = get_graphql_setting( 'garbage_collection_age', null, 'graphql_persisted_queries_section' );
+	if ( 1 >= $age || ! is_numeric( $age )) {
+		return;
+	}
+
+	$posts = Utils::getDocumentsBeforeDays( $age );
+	foreach ( $posts as $post_id ) {
+		wp_delete_post( $post_id );
+	}
+
+}, 10);