framework/base/ErrorHandler.php
<?php
/**
* @link https://www.yiiframework.com/
* @copyright Copyright (c) 2008 Yii Software LLC
* @license https://www.yiiframework.com/license/
*/
namespace yii\base;
use Yii;
use yii\helpers\VarDumper;
use yii\web\HttpException;
/**
* ErrorHandler handles uncaught PHP errors and exceptions.
*
* ErrorHandler is configured as an application component in [[\yii\base\Application]] by default.
* You can access that instance via `Yii::$app->errorHandler`.
*
* For more details and usage information on ErrorHandler, see the [guide article on handling errors](guide:runtime-handling-errors).
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @author Alexander Makarov <sam@rmcreative.ru>
* @author Carsten Brandt <mail@cebe.cc>
* @since 2.0
*/
abstract class ErrorHandler extends Component
{
/**
* @event Event an event that is triggered when the handler is called by shutdown function via [[handleFatalError()]].
* @since 2.0.46
*/
const EVENT_SHUTDOWN = 'shutdown';
/**
* @var bool whether to discard any existing page output before error display. Defaults to true.
*/
public $discardExistingOutput = true;
/**
* @var int the size of the reserved memory. A portion of memory is pre-allocated so that
* when an out-of-memory issue occurs, the error handler is able to handle the error with
* the help of this reserved memory. If you set this value to be 0, no memory will be reserved.
* Defaults to 256KB.
*/
public $memoryReserveSize = 262144;
/**
* @var \Throwable|null the exception that is being handled currently.
*/
public $exception;
/**
* @var bool if true - `handleException()` will finish script with `ExitCode::OK`.
* false - `ExitCode::UNSPECIFIED_ERROR`.
* @since 2.0.36
*/
public $silentExitOnException;
/**
* @var string Used to reserve memory for fatal error handler.
*/
private $_memoryReserve;
/**
* @var \Throwable from HHVM error that stores backtrace
*/
private $_hhvmException;
/**
* @var bool whether this instance has been registered using `register()`
*/
private $_registered = false;
/**
* @var string the current working directory
*/
private $_workingDirectory;
public function init()
{
$this->silentExitOnException = $this->silentExitOnException !== null ? $this->silentExitOnException : YII_ENV_TEST;
parent::init();
}
/**
* Register this error handler.
*
* @since 2.0.32 this will not do anything if the error handler was already registered
*/
public function register()
{
if (!$this->_registered) {
ini_set('display_errors', false);
set_exception_handler([$this, 'handleException']);
if (defined('HHVM_VERSION')) {
set_error_handler([$this, 'handleHhvmError']);
} else {
set_error_handler([$this, 'handleError']);
}
if ($this->memoryReserveSize > 0) {
$this->_memoryReserve = str_repeat('x', $this->memoryReserveSize);
}
// to restore working directory in shutdown handler
if (PHP_SAPI !== 'cli') {
$this->_workingDirectory = getcwd();
}
register_shutdown_function([$this, 'handleFatalError']);
$this->_registered = true;
}
}
/**
* Unregisters this error handler by restoring the PHP error and exception handlers.
* @since 2.0.32 this will not do anything if the error handler was not registered
*/
public function unregister()
{
if ($this->_registered) {
$this->_memoryReserve = null;
$this->_workingDirectory = null;
restore_error_handler();
restore_exception_handler();
$this->_registered = false;
}
}
/**
* Handles uncaught PHP exceptions.
*
* This method is implemented as a PHP exception handler.
*
* @param \Throwable $exception the exception that is not caught
*/
public function handleException($exception)
{
if ($exception instanceof ExitException) {
return;
}
$this->exception = $exception;
// disable error capturing to avoid recursive errors while handling exceptions
$this->unregister();
// set preventive HTTP status code to 500 in case error handling somehow fails and headers are sent
// HTTP exceptions will override this value in renderException()
if (PHP_SAPI !== 'cli') {
http_response_code(500);
}
try {
$this->logException($exception);
if ($this->discardExistingOutput) {
$this->clearOutput();
}
$this->renderException($exception);
if (!$this->silentExitOnException) {
\Yii::getLogger()->flush(true);
if (defined('HHVM_VERSION')) {
flush();
}
exit(1);
}
} catch (\Exception $e) {
// an other exception could be thrown while displaying the exception
$this->handleFallbackExceptionMessage($e, $exception);
} catch (\Throwable $e) {
// additional check for \Throwable introduced in PHP 7
$this->handleFallbackExceptionMessage($e, $exception);
}
$this->exception = null;
}
/**
* Handles exception thrown during exception processing in [[handleException()]].
* @param \Throwable $exception Exception that was thrown during main exception processing.
* @param \Throwable $previousException Main exception processed in [[handleException()]].
* @since 2.0.11
*/
protected function handleFallbackExceptionMessage($exception, $previousException)
{
$msg = "An Error occurred while handling another error:\n";
$msg .= (string) $exception;
$msg .= "\nPrevious exception:\n";
$msg .= (string) $previousException;
if (YII_DEBUG) {
if (PHP_SAPI === 'cli') {
echo $msg . "\n";
} else {
echo '<pre>' . htmlspecialchars($msg, ENT_QUOTES, Yii::$app->charset) . '</pre>';
}
$msg .= "\n\$_SERVER = " . VarDumper::export($_SERVER);
} else {
echo 'An internal server error occurred.';
}
error_log($msg);
if (defined('HHVM_VERSION')) {
flush();
}
exit(1);
}
/**
* Handles HHVM execution errors such as warnings and notices.
*
* This method is used as a HHVM error handler. It will store exception that will
* be used in fatal error handler
*
* @param int $code the level of the error raised.
* @param string $message the error message.
* @param string $file the filename that the error was raised in.
* @param int $line the line number the error was raised at.
* @param mixed $context
* @param mixed $backtrace trace of error
* @return bool whether the normal error handler continues.
*
* @throws ErrorException
* @since 2.0.6
*/
public function handleHhvmError($code, $message, $file, $line, $context, $backtrace)
{
if ($this->handleError($code, $message, $file, $line)) {
return true;
}
if (E_ERROR & $code) {
$exception = new ErrorException($message, $code, $code, $file, $line);
$ref = new \ReflectionProperty('\Exception', 'trace');
$ref->setAccessible(true);
$ref->setValue($exception, $backtrace);
$this->_hhvmException = $exception;
}
return false;
}
/**
* Handles PHP execution errors such as warnings and notices.
*
* This method is used as a PHP error handler. It will simply raise an [[ErrorException]].
*
* @param int $code the level of the error raised.
* @param string $message the error message.
* @param string $file the filename that the error was raised in.
* @param int $line the line number the error was raised at.
* @return bool whether the normal error handler continues.
*
* @throws ErrorException
*/
public function handleError($code, $message, $file, $line)
{
if (error_reporting() & $code) {
// load ErrorException manually here because autoloading them will not work
// when error occurs while autoloading a class
if (!class_exists('yii\\base\\ErrorException', false)) {
require_once __DIR__ . '/ErrorException.php';
}
$exception = new ErrorException($message, $code, $code, $file, $line);
if (PHP_VERSION_ID < 70400) {
// prior to PHP 7.4 we can't throw exceptions inside of __toString() - it will result a fatal error
$trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
array_shift($trace);
foreach ($trace as $frame) {
if ($frame['function'] === '__toString') {
$this->handleException($exception);
if (defined('HHVM_VERSION')) {
flush();
}
exit(1);
}
}
}
throw $exception;
}
return false;
}
/**
* Handles fatal PHP errors.
*/
public function handleFatalError()
{
unset($this->_memoryReserve);
if (isset($this->_workingDirectory)) {
// fix working directory for some Web servers e.g. Apache
chdir($this->_workingDirectory);
// flush memory
unset($this->_workingDirectory);
}
$error = error_get_last();
if ($error === null) {
return;
}
// load ErrorException manually here because autoloading them will not work
// when error occurs while autoloading a class
if (!class_exists('yii\\base\\ErrorException', false)) {
require_once __DIR__ . '/ErrorException.php';
}
if (!ErrorException::isFatalError($error)) {
return;
}
if (!empty($this->_hhvmException)) {
$this->exception = $this->_hhvmException;
} else {
$this->exception = new ErrorException(
$error['message'],
$error['type'],
$error['type'],
$error['file'],
$error['line']
);
}
unset($error);
$this->logException($this->exception);
if ($this->discardExistingOutput) {
$this->clearOutput();
}
$this->renderException($this->exception);
// need to explicitly flush logs because exit() next will terminate the app immediately
Yii::getLogger()->flush(true);
if (defined('HHVM_VERSION')) {
flush();
}
$this->trigger(static::EVENT_SHUTDOWN);
// ensure it is called after user-defined shutdown functions
register_shutdown_function(function () {
exit(1);
});
}
/**
* Renders the exception.
* @param \Throwable $exception the exception to be rendered.
*/
abstract protected function renderException($exception);
/**
* Logs the given exception.
* @param \Throwable $exception the exception to be logged
* @since 2.0.3 this method is now public.
*/
public function logException($exception)
{
$category = get_class($exception);
if ($exception instanceof HttpException) {
$category = 'yii\\web\\HttpException:' . $exception->statusCode;
} elseif ($exception instanceof \ErrorException) {
$category .= ':' . $exception->getSeverity();
}
Yii::error($exception, $category);
}
/**
* Removes all output echoed before calling this method.
*/
public function clearOutput()
{
// the following manual level counting is to deal with zlib.output_compression set to On
for ($level = ob_get_level(); $level > 0; --$level) {
if (!@ob_end_clean()) {
ob_clean();
}
}
}
/**
* Converts an exception into a PHP error.
*
* This method can be used to convert exceptions inside of methods like `__toString()`
* to PHP errors because exceptions cannot be thrown inside of them.
* @param \Throwable $exception the exception to convert to a PHP error.
* @return never
*/
public static function convertExceptionToError($exception)
{
trigger_error(static::convertExceptionToString($exception), E_USER_ERROR);
}
/**
* Converts an exception into a simple string.
* @param \Throwable $exception the exception being converted
* @return string the string representation of the exception.
*/
public static function convertExceptionToString($exception)
{
if ($exception instanceof UserException) {
return "{$exception->getName()}: {$exception->getMessage()}";
}
if (YII_DEBUG) {
return static::convertExceptionToVerboseString($exception);
}
return 'An internal server error occurred.';
}
/**
* Converts an exception into a string that has verbose information about the exception and its trace.
* @param \Throwable $exception the exception being converted
* @return string the string representation of the exception.
*
* @since 2.0.14
*/
public static function convertExceptionToVerboseString($exception)
{
if ($exception instanceof Exception) {
$message = "Exception ({$exception->getName()})";
} elseif ($exception instanceof ErrorException) {
$message = (string)$exception->getName();
} else {
$message = 'Exception';
}
$message .= " '" . get_class($exception) . "' with message '{$exception->getMessage()}' \n\nin "
. $exception->getFile() . ':' . $exception->getLine() . "\n\n"
. "Stack trace:\n" . $exception->getTraceAsString();
return $message;
}
}