WordPress/wp-includes/class-wp-fatal-error-handle...

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<?php
/**
* Error Protection API: WP_Fatal_Error_Handler class
*
* @package WordPress
* @since 5.2.0
*/
/**
* Core class used as the default shutdown handler for fatal errors.
*
* A drop-in 'fatal-error-handler.php' can be used to override the instance of this class and use a custom
* implementation for the fatal error handler that WordPress registers. The custom class should extend this class and
* can override its methods individually as necessary. The file must return the instance of the class that should be
* registered.
*
* @since 5.2.0
*/
Code Modernization: Add `AllowDynamicProperties` attribute to all (parent) classes. Dynamic (non-explicitly declared) properties are deprecated as of PHP 8.2 and are expected to become a fatal error in PHP 9.0. There are a number of ways to mitigate this: * If it is an accidental typo for a declared property: fix the typo. * For known properties: declare them on the class. * For unknown properties: add the magic `__get()`, `__set()`, et al. methods to the class or let the class extend `stdClass` which has highly optimized versions of these magic methods built in. * For unknown ''use'' of dynamic properties, the `#[AllowDynamicProperties]` attribute can be added to the class. The attribute will automatically be inherited by child classes. Trac ticket #56034 is open to investigate and handle the third and fourth type of situations, however it has become clear this will need more time and will not be ready in time for WP 6.1. To reduce “noise” in the meantime, both in the error logs of WP users moving onto PHP 8.2, in the test run logs of WP itself, in test runs of plugins and themes, as well as to prevent duplicate tickets from being opened for the same issue, this commit adds the `#[AllowDynamicProperties]` attribute to all “parent” classes in WP. The logic used for this commit is as follows: * If a class already has the attribute: no action needed. * If a class does not `extend`: add the attribute. * If a class does `extend`: - If it extends `stdClass`: no action needed (as `stdClass` supports dynamic properties). - If it extends a PHP native class: add the attribute. - If it extends a class from one of WP's external dependencies: add the attribute. * In all other cases: no action — the attribute should not be needed as child classes inherit from the parent. Whether or not a class contains magic methods has not been taken into account, as a review of the currently existing magic methods has shown that those are generally not sturdy enough and often even set dynamic properties (which they should not). See the [https://www.youtube.com/watch?v=vDZWepDQQVE live stream from August 16, 2022] for more details. This commit only affects classes in the `src` directory of WordPress core. * Tests should not get this attribute, but should be fixed to not use dynamic properties instead. Patches for this are already being committed under ticket #56033. * While a number bundled themes (2014, 2019, 2020, 2021) contain classes, they are not a part of this commit and may be updated separately. Reference: [https://wiki.php.net/rfc/deprecate_dynamic_properties PHP RFC: Deprecate dynamic properties]. Follow-up to [53922]. Props jrf, hellofromTonya, markjaquith, peterwilsoncc, costdev, knutsp, aristath. See #56513, #56034. Built from https://develop.svn.wordpress.org/trunk@54133 git-svn-id: http://core.svn.wordpress.org/trunk@53692 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2022-09-12 11:47:14 -04:00
#[AllowDynamicProperties]
class WP_Fatal_Error_Handler {
/**
* Runs the shutdown handler.
*
* This method is registered via `register_shutdown_function()`.
*
* @since 5.2.0
*/
public function handle() {
if ( defined( 'WP_SANDBOX_SCRAPING' ) && WP_SANDBOX_SCRAPING ) {
return;
}
// Do not trigger the fatal error handler while updates are being installed.
if ( wp_is_maintenance_mode() ) {
return;
}
try {
// Bail if no error found.
$error = $this->detect_error();
if ( ! $error ) {
return;
}
if ( ! isset( $GLOBALS['wp_locale'] ) && function_exists( 'load_default_textdomain' ) ) {
load_default_textdomain();
}
$handled = false;
if ( ! is_multisite() && wp_recovery_mode()->is_initialized() ) {
$handled = wp_recovery_mode()->handle_error( $error );
}
// Display the PHP error template if headers not sent.
if ( is_admin() || ! headers_sent() ) {
$this->display_error_template( $error, $handled );
}
} catch ( Exception $e ) {
// Catch exceptions and remain silent.
}
}
/**
* Detects the error causing the crash if it should be handled.
*
* @since 5.2.0
*
* @return array|null Error information returned by `error_get_last()`, or null
* if none was recorded or the error should not be handled.
*/
protected function detect_error() {
$error = error_get_last();
// No error, just skip the error handling code.
if ( null === $error ) {
return null;
}
// Bail if this error should not be handled.
if ( ! $this->should_handle_error( $error ) ) {
return null;
}
return $error;
}
/**
* Determines whether we are dealing with an error that WordPress should handle
* in order to protect the admin backend against WSODs.
*
* @since 5.2.0
*
* @param array $error Error information retrieved from `error_get_last()`.
* @return bool Whether WordPress should handle this error.
*/
protected function should_handle_error( $error ) {
$error_types_to_handle = array(
E_ERROR,
E_PARSE,
E_USER_ERROR,
E_COMPILE_ERROR,
E_RECOVERABLE_ERROR,
);
if ( isset( $error['type'] ) && in_array( $error['type'], $error_types_to_handle, true ) ) {
return true;
}
/**
* Filters whether a given thrown error should be handled by the fatal error handler.
*
* This filter is only fired if the error is not already configured to be handled by WordPress core. As such,
* it exclusively allows adding further rules for which errors should be handled, but not removing existing
* ones.
*
* @since 5.2.0
*
* @param bool $should_handle_error Whether the error should be handled by the fatal error handler.
* @param array $error Error information retrieved from `error_get_last()`.
*/
return (bool) apply_filters( 'wp_should_handle_php_error', false, $error );
}
/**
* Displays the PHP error template and sends the HTTP status code, typically 500.
*
* A drop-in 'php-error.php' can be used as a custom template. This drop-in should control the HTTP status code and
* print the HTML markup indicating that a PHP error occurred. Note that this drop-in may potentially be executed
* very early in the WordPress bootstrap process, so any core functions used that are not part of
* `wp-includes/load.php` should be checked for before being called.
*
* If no such drop-in is available, this will call {@see WP_Fatal_Error_Handler::display_default_error_template()}.
*
* @since 5.2.0
* @since 5.3.0 The `$handled` parameter was added.
*
* @param array $error Error information retrieved from `error_get_last()`.
* @param true|WP_Error $handled Whether Recovery Mode handled the fatal error.
*/
protected function display_error_template( $error, $handled ) {
if ( defined( 'WP_CONTENT_DIR' ) ) {
// Load custom PHP error template, if present.
$php_error_pluggable = WP_CONTENT_DIR . '/php-error.php';
if ( is_readable( $php_error_pluggable ) ) {
require_once $php_error_pluggable;
return;
}
}
// Otherwise, display the default error template.
$this->display_default_error_template( $error, $handled );
}
/**
* Displays the default PHP error template.
*
* This method is called conditionally if no 'php-error.php' drop-in is available.
*
* It calls {@see wp_die()} with a message indicating that the site is experiencing technical difficulties and a
* login link to the admin backend. The {@see 'wp_php_error_message'} and {@see 'wp_php_error_args'} filters can
* be used to modify these parameters.
*
* @since 5.2.0
* @since 5.3.0 The `$handled` parameter was added.
*
* @param array $error Error information retrieved from `error_get_last()`.
* @param true|WP_Error $handled Whether Recovery Mode handled the fatal error.
*/
protected function display_default_error_template( $error, $handled ) {
if ( ! function_exists( '__' ) ) {
wp_load_translations_early();
}
if ( ! function_exists( 'wp_die' ) ) {
require_once ABSPATH . WPINC . '/functions.php';
}
if ( ! class_exists( 'WP_Error' ) ) {
require_once ABSPATH . WPINC . '/class-wp-error.php';
}
if ( true === $handled && wp_is_recovery_mode() ) {
$message = __( 'There has been a critical error on this website, putting it in recovery mode. Please check the Themes and Plugins screens for more details. If you just installed or updated a theme or plugin, check the relevant page for that first.' );
} elseif ( is_protected_endpoint() && wp_recovery_mode()->is_initialized() ) {
if ( is_multisite() ) {
$message = __( 'There has been a critical error on this website. Please reach out to your site administrator, and inform them of this error for further assistance.' );
} else {
$message = __( 'There has been a critical error on this website. Please check your site admin email inbox for instructions.' );
}
} else {
$message = __( 'There has been a critical error on this website.' );
}
$message = sprintf(
'<p>%s</p><p><a href="%s">%s</a></p>',
$message,
/* translators: Documentation about troubleshooting. */
__( 'https://wordpress.org/documentation/article/faq-troubleshooting/' ),
__( 'Learn more about troubleshooting WordPress.' )
);
$args = array(
'response' => 500,
'exit' => false,
);
/**
* Filters the message that the default PHP error template displays.
*
* @since 5.2.0
*
* @param string $message HTML error message to display.
* @param array $error Error information retrieved from `error_get_last()`.
*/
$message = apply_filters( 'wp_php_error_message', $message, $error );
/**
* Filters the arguments passed to {@see wp_die()} for the default PHP error template.
*
* @since 5.2.0
*
* @param array $args Associative array of arguments passed to `wp_die()`. By default these contain a
* 'response' key, and optionally 'link_url' and 'link_text' keys.
* @param array $error Error information retrieved from `error_get_last()`.
*/
$args = apply_filters( 'wp_php_error_args', $args, $error );
$wp_error = new WP_Error(
'internal_server_error',
$message,
array(
'error' => $error,
)
);
wp_die( $wp_error, '', $args );
}
}