feat: add mu-plugin preventing transients to be saved into database, and cleaning up existing transients from database weekly.

Author: Rahe

default-no-transients.php

@@ -0,0 +1,146 @@
+<?php
+/*
+Plugin Name: No transients
+Version: 1.0.0
+Plugin URI: https://beapi.fr
+Author: Be API
+Author URI: https://beapi.fr
+
+----
+
+Copyright 2025 Be API Technical team ([email protected])
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+namespace BeAPI;
+
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+/**
+ * Class to prevent transients from being stored in the database
+ * since we're using Redis for object caching
+ */
+class NoTransients {
+	/**
+	 * Initialize the class and set up hooks
+	 */
+	public function __construct() {
+
+		
+		// Prevent transients from being retrieved
+		add_filter( 'pre_option', [ $this, 'prevent_transient_retrieval' ], 10, 2 );
+
+		// Remove transients from alloptions
+		add_filter( 'alloptions', [ $this, 'remove_transients_from_alloptions' ] );
+
+		// Prevent new transients from being added
+		add_action( 'added_option', [ $this, 'delete_transient_option' ] );
+
+		// Prevent transients from being updated
+		add_action( 'updated_option', [ $this, 'delete_transient_option' ] );
+		
+		// Set up cleanup cron job
+		add_action( 'init', [ $this, 'setup_cleanup_cron' ] );
+
+		// Show admin notice if no external object cache is being used
+		add_action( 'admin_notices', [ $this, 'show_admin_notice' ] );
+
+		add_action( 'beapi_clean_transients', [ $this, 'cleanup_transients' ] );
+	}
+
+	/**
+	 * Make transients appear expired by returning 0 for timeout options
+	 *
+	 * @param mixed $pre The pre-option value
+	 * @param string $option The option name
+	 * @return mixed The modified pre-option value
+	 */
+	public function prevent_transient_retrieval( $pre, $option ) {
+		// If it's a transient timeout, return 0 to make it appear expired
+		if ( str_starts_with( $option, '_transient_timeout' ) ) {
+			return 0;
+		}
+
+		return $pre;
+	}
+
+	/**
+	 * Remove transients from alloptions array and delete them from database
+	 * This is because alloptions is called into the get_transient function, and expiration is not checked if the transient is in alloptions.
+	 *
+	 * @param array $alloptions The array of all autoloaded options
+	 * @return array The filtered options array
+	 */
+	public function remove_transients_from_alloptions( $alloptions ) {
+		foreach ( $alloptions as $option => $value ) {
+			if ( ! str_starts_with( $option, '_transient' ) ) {
+				continue;
+			}
+
+			unset( $alloptions[ $option ] );
+			delete_option( $option );
+		}
+
+		return $alloptions;
+	}
+
+	/**
+	 * Delete transient options when they're added or updated
+	 *
+	 * @param string $option The option name
+	 * @param mixed $value The option value
+	 */
+	public function delete_transient_option( $option ) {
+		if ( str_starts_with( $option, '_transient' ) ) {
+			delete_option( $option );
+		}
+	}
+
+	/**
+	 * Set up weekly cron job to clean up transients
+	 */
+	public function setup_cleanup_cron() {
+		if ( ! wp_next_scheduled( 'beapi_clean_transients' ) ) {
+			wp_schedule_event( time(), 'weekly', 'beapi_clean_transients' );
+		}
+	}
+
+	/**
+	 * Clean up all transients from the database
+	 */
+	public function cleanup_transients() {
+		global $wpdb;
+
+		// Delete all transients
+		$wpdb->query( "DELETE FROM $wpdb->options WHERE option_name LIKE '_transient_%'" );
+	}
+
+	/**
+	 * Show admin notice if no external object cache is being used
+	 * The removal of transients when not object cache is a big performance issue
+	 */
+	public function show_admin_notice() {
+		if ( wp_using_ext_object_cache() || ! current_user_can( 'manage_options' ) ) {
+			return;
+		}
+
+		echo '<div class="notice notice-error"><p style="font-size: 40px;">Beware transients are not written in database. Please remove <strong>' . esc_html( wp_basename( __FILE__ ) ) . '</strong> from the mu-plugins folder.</p></div>';
+	}
+}
+
+// Initialize the class
+new NoTransients();