目录
WordPress 在更新程序、主题、插件的时候会进入维护模式并提示“正在执行例行维护，请一分钟后回来。”，英文为“Briefly unavailable for scheduled maintenance. Check back in a minute.”。关于该函数的定义位于wp-includes 文件夹下的 load.php 文件中，具体代码如下：
/**
* Die with a maintenance message when conditions are met.
*
* Checks for a file in the WordPress root directory named ".maintenance".
* This file will contain the variable $upgrading, set to the time the file
* was created. If the file was created less than 10 minutes ago, WordPress
* enters maintenance mode and displays a message.
*
* The default message can be replaced by using a drop-in (maintenance.php in
* the wp-content directory).
*
* @since 3.0.0
* @access private
*
* @global int $upgrading the unix timestamp marking when upgrading WordPress began.
*/
function wp_maintenance() {
if ( ! file_exists( ABSPATH . '.maintenance' ) || wp_installing() )
return;
global $upgrading;
include( ABSPATH . '.maintenance' );
// If the $upgrading timestamp is older than 10 minutes, don't die.
if ( ( time() - $upgrading ) >= 600 )
return;
/**
* Filters whether to enable maintenance mode.
*
* This filter runs before it can be used by plugins. It is designed for
* non-web runtimes. If this filter returns true, maintenance mode will be
* active and the request will end. If false, the request will be allowed to
* continue processing even if maintenance mode should be active.
*
* @since 4.6.0
*
* @param bool $enable_checks Whether to enable maintenance mode. Default true.
* @param int $upgrading The timestamp set in the .maintenance file.
*/
if ( ! apply_filters( 'enable_maintenance_mode', true, $upgrading ) ) {
return;
}
if ( file_exists( WP_CONTENT_DIR . '/maintenance.php' ) ) {
require_once( WP_CONTENT_DIR . '/maintenance.php' );
die();
}
wp_load_translations_early();
$protocol = wp_get_server_protocol();
header( "$protocol 503 Service Unavailable", true, 503 );
header( 'Content-Type: text/html; charset=utf-8' );
header( 'Retry-After: 600' );
?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"<?php if ( is_rtl() ) echo ' dir="rtl"'; ?>>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title><?php _e( 'Maintenance' ); ?></title>
</head>
<body>
<h1><?php _e( 'Briefly unavailable for scheduled maintenance. Check back in a minute.' ); ?></h1>
</body>
</html>
<?php
die();
}如果你不喜欢默认的提示文字，可以在这里将默认的“Briefly unavailable for scheduled maintenance. Check back in a minute.”替换为你想要的任意文字或代码。
参考文档：https://developer.wordpress.org/reference/functions/wp_maintenance/
