akismet.php

<?php
/*
Plugin Name: Akismet Anti-Spam
Plugin URI: https://akismet.com/
Description: Used by millions, Akismet is quite possibly the best way in the world to <strong>protect your blog from spam</strong>. It keeps your site protected even while you sleep. To get started: activate the Akismet plugin and then go to your Akismet Settings page to set up your API key.
Version: 5.1
Author: Automattic
Author URI: https://automattic.com/wordpress-plugins/
License: GPLv2 or later
Text Domain: akismet
*/

// Avoid loading Akismet altogether if VIP_JETPACK_SKIP_LOAD is set to true (Jetpack is required for Akismet to work in VIP)
if ( defined( 'VIP_JETPACK_SKIP_LOAD' ) && true === VIP_JETPACK_SKIP_LOAD ) {
	return;
}

// Avoid loading Akismet if VIP_AKISMET_SKIP_LOAD is set to true
if ( defined( 'VIP_AKISMET_SKIP_LOAD' ) && true === VIP_AKISMET_SKIP_LOAD ) {
	return;
}

// Load the core Akismet plugin
require_once __DIR__ . '/akismet/akismet.php';

// By default, Akismet tries to delete batches of 10,000 at a time.
// That's way too high. Let's set a more reasonable limit.
function wpcom_vip_akismet_delete_limit() {
	return 500;
}
add_filter( 'akismet_delete_comment_limit', 'wpcom_vip_akismet_delete_limit' );

// Identify outgoing requests as coming from VIP Go
function wpcom_vip_akismet_ua( $ua ) {
	return $ua . ' | platform:vipgo';
}
add_filter( 'akismet_ua', 'wpcom_vip_akismet_ua' );

// Limit cache/alloptions invalidations when getting inundated with spam comments.
function wpcom_vip_akismet_spam_count_incr( $val ) {
	// if the blog has a small number of comments, increment the counter by 1 every time
	$current = get_option( 'akismet_spam_count' );
	if ( $current < 150 ) {
		return $val;
	}

	// If it has a large number of comments, increment it by 3 one third of the time
	$random = mt_rand( 1, 3 );  // phpcs:ignore WordPress.WP.AlternativeFunctions.rand_mt_rand
	if ( 3 === $random ) {
		return 3;
	}

	return 0;
}
add_filter( 'akismet_spam_count_incr', 'wpcom_vip_akismet_spam_count_incr' );

/**
 * @return bool True if the Akismet key in the site is not existent or not valid
 */
function is_akismet_key_invalid(): bool {
	if ( class_exists( 'Akismet' ) ) {
		$key        = Akismet::get_api_key();
		$key_status = Akismet::check_key_status( $key );
		return ! $key_status || ! $key_status[1] || 'invalid' === $key_status[1];
	}

	return false;
}