yii2-bootstrap/framework/base/ErrorHandler.php

<?php
/**
 * ErrorHandler class file.
 *
 * @link http://www.yiiframework.com/
 * @copyright Copyright &copy; 2008-2012 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace yii\base;

/**
 * ErrorHandler handles uncaught PHP errors and exceptions.
 *
 * It displays these errors using appropriate views based on the
 * nature of the error and the mode the application runs at.
 * It also chooses the most preferred language for displaying the error.
 *
 * ErrorHandler uses two sets of views:
 * <ul>
 * <li>development views, named as <code>exception.php</code>;
 * <li>production views, named as <code>error&lt;StatusCode&gt;.php</code>;
 * </ul>
 * where &lt;StatusCode&gt; stands for the HTTP error code (e.g. error500.php).
 * Localized views are named similarly but located under a subdirectory
 * whose name is the language code (e.g. zh_cn/error500.php).
 *
 * Development views are displayed when the application is in debug mode
 * (i.e. YII_DEBUG is defined as true). Detailed error information with source code
 * are displayed in these views. Production views are meant to be shown
 * to end-users and are used when the application is in production mode.
 * For security reasons, they only display the error message without any
 * sensitive information.
 *
 * ErrorHandler looks for the view templates from the following locations in order:
 * <ol>
 * <li><code>themes/ThemeName/views/system</code>: when a theme is active.</li>
 * <li><code>protected/views/system</code></li>
 * <li><code>framework/views</code></li>
 * </ol>
 * If the view is not found in a directory, it will be looked for in the next directory.
 *
 * The property {@link maxSourceLines} can be changed to specify the number
 * of source code lines to be displayed in development views.
 *
 * ErrorHandler is a core application component that can be accessed via
 * {@link CApplication::getErrorHandler()}.
 *
 * @property array $error The error details. Null if there is no error.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
class ErrorHandler extends ApplicationComponent
{
	/**
	 * @var integer maximum number of source code lines to be displayed. Defaults to 25.
	 */
	public $maxSourceLines = 25;

	/**
	 * @var integer maximum number of trace source code lines to be displayed. Defaults to 10.
	 */
	public $maxTraceSourceLines = 10;

	/**
	 * @var string the application administrator information (could be a name or email link). It is displayed in error pages to end users. Defaults to 'the webmaster'.
	 */
	public $adminInfo = 'the webmaster';
	/**
	 * @var boolean whether to discard any existing page output before error display. Defaults to true.
	 */
	public $discardExistingOutput = true;
	/**
	 * @var string the route (eg 'site/error') to the controller action that will be used to display external errors.
	 * Inside the action, it can retrieve the error information by Yii::app()->errorHandler->error.
	 * This property defaults to null, meaning ErrorHandler will handle the error display.
	 */
	public $errorAction;

	private $_error;
	public $exception;
	public $compactOutput;

	public function init()
	{
		set_exception_handler(array($this, 'handleException'));
		set_error_handler(array($this, 'handleError'), error_reporting());
	}

	protected function logException($exception)
	{
		$category = get_class($exception);
		if ($exception instanceof HttpException) {
			$category .= '\\' . $exception->statusCode;
		} elseif ($exception instanceof \ErrorException) {
			$category .= '\\' . $exception->getSeverity();
		}
		\Yii::error((string)$exception, $category);
	}

	protected 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) {
			@ob_end_clean();
		}
	}

	protected function simple()
	{
		if (YII_DEBUG) {
			echo '<h1>' . get_class($exception) . "</h1>\n";
			echo '<p>' . $exception->getMessage() . ' (' . $exception->getFile() . ':' . $exception->getLine() . ')</p>';
			echo '<pre>' . $exception->getTraceAsString() . '</pre>';
		} else
		{
			echo '<h1>' . get_class($exception) . "</h1>\n";
			echo '<p>' . $exception->getMessage() . '</p>';
		}
	}

	/**
	 * @param \Exception $exception
	 */
	public function handleException($exception)
	{
		$this->exception = $exception;

		// disable error capturing to avoid recursive errors
		restore_error_handler();
		restore_exception_handler();

		$this->logException($exception);
		if ($this->discardExistingOutput) {
			$this->clearOutput();
		}

		if ($this->compactOutput === null) {
			// not in Web application, or not in AJAX request
			$this->compactOutput = !(\Yii::$application instanceof \yii\web\Application) || isset($_SERVER['HTTP_X_REQUESTED_WITH']) && $_SERVER['HTTP_X_REQUESTED_WITH']==='XMLHttpRequest';
		}

		if ($this->compactOutput) {
			$this->simple();
			return;
		}

		if (($trace = $this->getExactTrace($exception)) === null) {
			$fileName = $exception->getFile();
			$errorLine = $exception->getLine();
		} else {
			$fileName = $trace['file'];
			$errorLine = $trace['line'];
		}

		$trace = $exception->getTrace();
		foreach ($trace as $i => $t) {
			if (!isset($t['file'])) {
				$trace[$i]['file'] = 'unknown';
			}
			if (!isset($t['line'])) {
				$trace[$i]['line'] = 0;
			}
			if (!isset($t['function'])) {
				$trace[$i]['function'] = 'unknown';
			}
			unset($trace[$i]['object']);
		}

		$this->_error = $data = array(
			'code' => $exception instanceof HttpException ? $exception->statusCode : 500,
			'type' => get_class($exception),
			'errorCode' => $exception->getCode(),
			'message' => $exception->getMessage(),
			'file' => $fileName,
			'line' => $errorLine,
			'trace' => $exception->getTraceAsString(),
			'traces' => $trace,
		);

		if (!headers_sent()) {
			header("HTTP/1.0 {$data['code']} " . get_class($exception));
		}

		if ($exception instanceof HttpException || !YII_DEBUG) {
			$this->render('error', $data);
		} else {
			$this->render('exception', $data);
		}
	}

	/**
	 * Returns the details about the error that is currently being handled.
	 * The error is returned in terms of an array, with the following information:
	 * <ul>
	 * <li>code - the HTTP status code (e.g. 403, 500)</li>
	 * <li>type - the error type (e.g. 'CHttpException', 'PHP Error')</li>
	 * <li>message - the error message</li>
	 * <li>file - the name of the PHP script file where the error occurs</li>
	 * <li>line - the line number of the code where the error occurs</li>
	 * <li>trace - the call stack of the error</li>
	 * <li>source - the context source code where the error occurs</li>
	 * </ul>
	 * @return array the error details. Null if there is no error.
	 */
	public function getError()
	{
		return $this->_error;
	}

	/**
	 * Handles the PHP error.
	 * @param CErrorEvent $event the PHP error event
	 */
	protected function handleError($event)
	{
		$trace = debug_backtrace();
		// skip the first 3 stacks as they do not tell the error position
		if (count($trace) > 3)
			$trace = array_slice($trace, 3);
		$traceString = '';
		foreach ($trace as $i => $t)
		{
			if (!isset($t['file']))
				$trace[$i]['file'] = 'unknown';

			if (!isset($t['line']))
				$trace[$i]['line'] = 0;

			if (!isset($t['function']))
				$trace[$i]['function'] = 'unknown';

			$traceString .= "#$i {$trace[$i]['file']}({$trace[$i]['line']}): ";
			if (isset($t['object']) && is_object($t['object']))
				$traceString .= get_class($t['object']) . '->';
			$traceString .= "{$trace[$i]['function']}()\n";

			unset($trace[$i]['object']);
		}

		$app = Yii::app();
		if ($app instanceof CWebApplication) {
			switch ($event->code)
			{
				case E_WARNING:
					$type = 'PHP warning';
					break;
				case E_NOTICE:
					$type = 'PHP notice';
					break;
				case E_USER_ERROR:
					$type = 'User error';
					break;
				case E_USER_WARNING:
					$type = 'User warning';
					break;
				case E_USER_NOTICE:
					$type = 'User notice';
					break;
				case E_RECOVERABLE_ERROR:
					$type = 'Recoverable error';
					break;
				default:
					$type = 'PHP error';
			}
			$this->_error = $data = array(
				'code' => 500,
				'type' => $type,
				'message' => $event->message,
				'file' => $event->file,
				'line' => $event->line,
				'trace' => $traceString,
				'traces' => $trace,
			);
			if (!headers_sent())
				header("HTTP/1.0 500 PHP Error");
			if ($this->isAjaxRequest())
				$app->displayError($event->code, $event->message, $event->file, $event->line);
			else if (YII_DEBUG)
				$this->render('exception', $data);
			else
				$this->render('error', $data);
		}
		else
			$app->displayError($event->code, $event->message, $event->file, $event->line);
	}

	/**
	 * Returns the exact trace where the problem occurs.
	 * @param \Exception $exception the uncaught exception
	 * @return array the exact trace where the problem occurs
	 */
	protected function getExactTrace($exception)
	{
		$traces = $exception->getTrace();
		foreach ($traces as $trace) {
			// property access exception
			if (isset($trace['function']) && ($trace['function'] === '__get' || $trace['function'] === '__set')) {
				return $trace;
			}
		}
		return null;
	}

	/**
	 * Renders the view.
	 * @param string $view the view name (file name without extension).
	 * See {@link getViewFile} for how a view file is located given its name.
	 * @param array $data data to be passed to the view
	 */
	protected function render($view, $data)
	{
		if ($view === 'error' && $this->errorAction !== null)
			Yii::app()->runController($this->errorAction);
		else
		{
			// additional information to be passed to view
			$data['version'] = $this->getVersionInfo();
			$data['time'] = time();
			$data['admin'] = $this->adminInfo;
			include($this->getViewFile($view, $data['code']));
		}
	}

	/**
	 * Determines which view file should be used.
	 * @param string $view view name (either 'exception' or 'error')
	 * @param integer $code HTTP status code
	 * @return string view file path
	 */
	protected function getViewFile($view, $code)
	{
		$viewPaths = array(
			Yii::app()->getTheme() === null ? null : Yii::app()->getTheme()->getSystemViewPath(),
			Yii::app() instanceof CWebApplication ? Yii::app()->getSystemViewPath() : null,
			YII_PATH . DIRECTORY_SEPARATOR . 'views',
		);

		foreach ($viewPaths as $i => $viewPath)
		{
			if ($viewPath !== null) {
				$viewFile = $this->getViewFileInternal($viewPath, $view, $code, $i === 2 ? 'en_us' : null);
				if (is_file($viewFile))
					return $viewFile;
			}
		}
	}

	/**
	 * Looks for the view under the specified directory.
	 * @param string $viewPath the directory containing the views
	 * @param string $view view name (either 'exception' or 'error')
	 * @param integer $code HTTP status code
	 * @param string $srcLanguage the language that the view file is in
	 * @return string view file path
	 */
	protected function getViewFileInternal($viewPath, $view, $code, $srcLanguage = null)
	{
		$app = Yii::app();
		if ($view === 'error') {
			$viewFile = $app->findLocalizedFile($viewPath . DIRECTORY_SEPARATOR . "error{$code}.php", $srcLanguage);
			if (!is_file($viewFile))
				$viewFile = $app->findLocalizedFile($viewPath . DIRECTORY_SEPARATOR . 'error.php', $srcLanguage);
		}
		else
			$viewFile = $viewPath . DIRECTORY_SEPARATOR . "exception.php";
		return $viewFile;
	}

	/**
	 * Returns server version information.
	 * If the application is in production mode, empty string is returned.
	 * @return string server version information. Empty if in production mode.
	 */
	protected function getVersionInfo()
	{
		if (YII_DEBUG) {
			$version = '<a href="http://www.yiiframework.com/">Yii Framework</a>/' . \Yii::getVersion();
			if (isset($_SERVER['SERVER_SOFTWARE'])) {
				$version = $_SERVER['SERVER_SOFTWARE'] . ' ' . $version;
			}
		} else {
			$version = '';
		}
		return $version;
	}

	/**
	 * Converts arguments array to its string representation
	 *
	 * @param array $args arguments array to be converted
	 * @return string string representation of the arguments array
	 */
	protected function argumentsToString($args)
	{
		$count = 0;

		$isAssoc = $args !== array_values($args);

		foreach ($args as $key => $value)
		{
			$count++;
			if ($count >= 5) {
				if ($count > 5)
					unset($args[$key]);
				else
					$args[$key] = '...';
				continue;
			}

			if (is_object($value))
				$args[$key] = get_class($value);
			else if (is_bool($value))
				$args[$key] = $value ? 'true' : 'false';
			else if (is_string($value)) {
				if (strlen($value) > 64)
					$args[$key] = '"' . substr($value, 0, 64) . '..."';
				else
					$args[$key] = '"' . $value . '"';
			}
			else if (is_array($value))
				$args[$key] = 'array(' . $this->argumentsToString($value) . ')';
			else if ($value === null)
				$args[$key] = 'null';
			else if (is_resource($value))
				$args[$key] = 'resource';

			if (is_string($key)) {
				$args[$key] = '"' . $key . '" => ' . $args[$key];
			}
			else if ($isAssoc) {
				$args[$key] = $key . ' => ' . $args[$key];
			}
		}
		$out = implode(", ", $args);

		return $out;
	}

	/**
	 * Returns a value indicating whether the call stack is from application code.
	 * @param array $trace the trace data
	 * @return boolean whether the call stack is from application code.
	 */
	protected function isCoreCode($trace)
	{
		if (isset($trace['file'])) {
			$systemPath = realpath(dirname(__FILE__) . '/..');
			return $trace['file'] === 'unknown' || strpos(realpath($trace['file']), $systemPath . DIRECTORY_SEPARATOR) === 0;
		}
		return false;
	}

	/**
	 * Renders the source code around the error line.
	 * @param string $file source file path
	 * @param integer $errorLine the error line number
	 * @param integer $maxLines maximum number of lines to display
	 * @return string the rendering result
	 */
	protected function renderSourceCode($file, $errorLine, $maxLines)
	{
		$errorLine--; // adjust line number to 0-based from 1-based
		if ($errorLine < 0 || ($lines = @file($file)) === false || ($lineCount = count($lines)) <= $errorLine)
			return '';

		$halfLines = (int)($maxLines / 2);
		$beginLine = $errorLine - $halfLines > 0 ? $errorLine - $halfLines : 0;
		$endLine = $errorLine + $halfLines < $lineCount ? $errorLine + $halfLines : $lineCount - 1;
		$lineNumberWidth = strlen($endLine + 1);

		$output = '';
		for ($i = $beginLine; $i <= $endLine; ++$i)
		{
			$isErrorLine = $i === $errorLine;
			$code = sprintf("<span class=\"ln" . ($isErrorLine ? ' error-ln' : '') . "\">%0{$lineNumberWidth}d</span> %s", $i + 1, CHtml::encode(str_replace("\t", '    ', $lines[$i])));
			if (!$isErrorLine)
				$output .= $code;
			else
				$output .= '<span class="error">' . $code . '</span>';
		}
		return '<div class="code"><pre>' . $output . '</pre></div>';
	}

	/**
	 * Handles PHP execution errors such as warnings, notices.
	 *
	 * This method is implemented as a PHP error handler. It requires
	 * that constant YII_ENABLE_ERROR_HANDLER be defined true.
	 *
	 * This method will first raise an `error` event.
	 * If the error is not handled by any event handler, it will call
	 * {@link getErrorHandler errorHandler} to process the error.
	 *
	 * The application will be terminated by this method.
	 *
	 * @param integer $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 integer $line the line number the error was raised at
	 */
	public function handleError($code, $message, $file, $line)
	{
		throw new \ErrorException($message, 0, $code, $file, $line);
	}
}