3 * Exception class and handler.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
24 * @defgroup Exception Exception
32 class MWException
extends Exception
{
36 * Should the exception use $wgOut to output the error?
40 function useOutputPage() {
41 return $this->useMessageCache() &&
42 !empty( $GLOBALS['wgFullyInitialised'] ) &&
43 !empty( $GLOBALS['wgOut'] ) &&
44 !empty( $GLOBALS['wgTitle'] );
48 * Can the extension use the Message class/wfMessage to get i18n-ed messages?
52 function useMessageCache() {
55 foreach ( $this->getTrace() as $frame ) {
56 if ( isset( $frame['class'] ) && $frame['class'] === 'LocalisationCache' ) {
61 return $wgLang instanceof Language
;
65 * Run hook to allow extensions to modify the text of the exception
67 * @param string $name class name of the exception
68 * @param array $args arguments to pass to the callback functions
69 * @return string|null string to output or null if any hook has been called
71 function runHooks( $name, $args = array() ) {
72 global $wgExceptionHooks;
74 if ( !isset( $wgExceptionHooks ) ||
!is_array( $wgExceptionHooks ) ) {
75 return null; // Just silently ignore
78 if ( !array_key_exists( $name, $wgExceptionHooks ) ||
!is_array( $wgExceptionHooks[$name] ) ) {
82 $hooks = $wgExceptionHooks[$name];
83 $callargs = array_merge( array( $this ), $args );
85 foreach ( $hooks as $hook ) {
86 if ( is_string( $hook ) ||
( is_array( $hook ) && count( $hook ) >= 2 && is_string( $hook[0] ) ) ) { // 'function' or array( 'class', hook' )
87 $result = call_user_func_array( $hook, $callargs );
92 if ( is_string( $result ) ) {
100 * Get a message from i18n
102 * @param string $key message name
103 * @param string $fallback default message if the message cache can't be
104 * called by the exception
105 * The function also has other parameters that are arguments for the message
106 * @return string message with arguments replaced
108 function msg( $key, $fallback /*[, params...] */ ) {
109 $args = array_slice( func_get_args(), 2 );
111 if ( $this->useMessageCache() ) {
112 return wfMessage( $key, $args )->plain();
114 return wfMsgReplaceArgs( $fallback, $args );
119 * If $wgShowExceptionDetails is true, return a HTML message with a
120 * backtrace to the error, otherwise show a message to ask to set it to true
121 * to show that information.
123 * @return string html to output
126 global $wgShowExceptionDetails;
128 if ( $wgShowExceptionDetails ) {
129 return '<p>' . nl2br( htmlspecialchars( $this->getMessage() ) ) .
130 '</p><p>Backtrace:</p><p>' . nl2br( htmlspecialchars( MWExceptionHandler
::formatRedactedTrace( $this ) ) ) .
133 return "<div class=\"errorbox\">" .
134 '[' . $this->getLogId() . '] ' .
135 gmdate( 'Y-m-d H:i:s' ) .
136 ": Fatal exception of type " . get_class( $this ) . "</div>\n" .
137 "<!-- Set \$wgShowExceptionDetails = true; " .
138 "at the bottom of LocalSettings.php to show detailed " .
139 "debugging information. -->";
144 * Get the text to display when reporting the error on the command line.
145 * If $wgShowExceptionDetails is true, return a text message with a
146 * backtrace to the error.
151 global $wgShowExceptionDetails;
153 if ( $wgShowExceptionDetails ) {
154 return $this->getMessage() .
155 "\nBacktrace:\n" . MWExceptionHandler
::formatRedactedTrace( $this ) . "\n";
157 return "Set \$wgShowExceptionDetails = true; " .
158 "in LocalSettings.php to show detailed debugging information.\n";
163 * Return the title of the page when reporting this error in a HTTP response.
167 function getPageTitle() {
168 return $this->msg( 'internalerror', "Internal error" );
172 * Get a random ID for this error.
173 * This allows to link the exception to its corresponding log entry when
174 * $wgShowExceptionDetails is set to false.
178 function getLogId() {
179 if ( $this->logId
=== null ) {
180 $this->logId
= wfRandomString( 8 );
186 * Return the requested URL and point to file and line number from which the
191 function getLogMessage() {
194 $id = $this->getLogId();
195 $file = $this->getFile();
196 $line = $this->getLine();
197 $message = $this->getMessage();
199 if ( isset( $wgRequest ) && !$wgRequest instanceof FauxRequest
) {
200 $url = $wgRequest->getRequestURL();
208 return "[$id] $url Exception from line $line of $file: $message";
212 * Output the exception report using HTML.
214 function reportHTML() {
216 if ( $this->useOutputPage() ) {
217 $wgOut->prepareErrorPage( $this->getPageTitle() );
219 $hookResult = $this->runHooks( get_class( $this ) );
221 $wgOut->addHTML( $hookResult );
223 $wgOut->addHTML( $this->getHTML() );
228 header( "Content-Type: text/html; charset=utf-8" );
229 echo "<!doctype html>\n" .
231 '<title>' . htmlspecialchars( $this->getPageTitle() ) . '</title>' .
234 $hookResult = $this->runHooks( get_class( $this ) . "Raw" );
238 echo $this->getHTML();
241 echo "</body></html>\n";
246 * Output a report about the exception and takes care of formatting.
247 * It will be either HTML or plain text based on isCommandLine().
252 $this->logException();
254 if ( defined( 'MW_API' ) ) {
255 // Unhandled API exception, we can't be sure that format printer is alive
256 header( 'MediaWiki-API-Error: internal_api_error_' . get_class( $this ) );
257 wfHttpError( 500, 'Internal Server Error', $this->getText() );
258 } elseif ( self
::isCommandLine() ) {
259 MWExceptionHandler
::printError( $this->getText() );
261 header( "HTTP/1.1 500 MediaWiki exception" );
262 header( "Status: 500 MediaWiki exception", true );
263 header( "Content-Type: $wgMimeType; charset=utf-8", true );
270 * Log the error message to the exception log (if enabled)
272 function logException() {
273 global $wgLogExceptionBacktrace;
275 $log = $this->getLogMessage();
277 if ( $wgLogExceptionBacktrace ) {
278 wfDebugLog( 'exception', $log . "\n" . MWExceptionHandler
::formatRedactedTrace( $this ) . "\n" );
280 wfDebugLog( 'exception', $log );
286 * Check whether we are in command line mode or not to report the exception
287 * in the correct format.
291 static function isCommandLine() {
292 return !empty( $GLOBALS['wgCommandLineMode'] );
297 * Exception class which takes an HTML error message, and does not
298 * produce a backtrace. Replacement for OutputPage::fatalError().
303 class FatalError
extends MWException
{
309 return $this->getMessage();
316 return $this->getMessage();
321 * An error page which can definitely be safely rendered using the OutputPage.
326 class ErrorPageError
extends MWException
{
327 public $title, $msg, $params;
330 * Note: these arguments are keys into wfMessage(), not text!
332 * @param string|Message $title Message key (string) for page title, or a Message object
333 * @param string|Message $msg Message key (string) for error text, or a Message object
334 * @param array $params with parameters to wfMessage()
336 function __construct( $title, $msg, $params = null ) {
337 $this->title
= $title;
339 $this->params
= $params;
341 // Bug 44111: Messages in the log files should be in English and not
342 // customized by the local wiki. So get the default English version for
343 // passing to the parent constructor. Our overridden report() below
344 // makes sure that the page shown to the user is not forced to English.
345 if ( $msg instanceof Message
) {
346 $enMsg = clone( $msg );
348 $enMsg = wfMessage( $msg, $params );
350 $enMsg->inLanguage( 'en' )->useDatabase( false );
351 parent
::__construct( $enMsg->text() );
357 $wgOut->showErrorPage( $this->title
, $this->msg
, $this->params
);
363 * Show an error page on a badtitle.
364 * Similar to ErrorPage, but emit a 400 HTTP error code to let mobile
365 * browser it is not really a valid content.
370 class BadTitleError
extends ErrorPageError
{
372 * @param string|Message $msg A message key (default: 'badtitletext')
373 * @param array $params parameter to wfMessage()
375 function __construct( $msg = 'badtitletext', $params = null ) {
376 parent
::__construct( 'badtitle', $msg, $params );
380 * Just like ErrorPageError::report() but additionally set
381 * a 400 HTTP status code (bug 33646).
386 // bug 33646: a badtitle error page need to return an error code
387 // to let mobile browser now that it is not a normal page.
388 $wgOut->setStatusCode( 400 );
395 * Show an error when a user tries to do something they do not have the necessary
401 class PermissionsError
extends ErrorPageError
{
402 public $permission, $errors;
404 function __construct( $permission, $errors = array() ) {
407 $this->permission
= $permission;
409 if ( !count( $errors ) ) {
411 array( 'User', 'makeGroupLinkWiki' ),
412 User
::getGroupsWithPermission( $this->permission
)
416 $errors[] = array( 'badaccess-groups', $wgLang->commaList( $groups ), count( $groups ) );
418 $errors[] = array( 'badaccess-group0' );
422 $this->errors
= $errors;
428 $wgOut->showPermissionsErrorPage( $this->errors
, $this->permission
);
434 * Show an error when the wiki is locked/read-only and the user tries to do
435 * something that requires write access.
440 class ReadOnlyError
extends ErrorPageError
{
441 public function __construct() {
451 * Show an error when the user hits a rate limit.
456 class ThrottledError
extends ErrorPageError
{
457 public function __construct() {
460 'actionthrottledtext'
464 public function report() {
466 $wgOut->setStatusCode( 503 );
472 * Show an error when the user tries to do something whilst blocked.
477 class UserBlockedError
extends ErrorPageError
{
478 public function __construct( Block
$block ) {
479 // @todo FIXME: Implement a more proper way to get context here.
480 $params = $block->getPermissionsError( RequestContext
::getMain() );
481 parent
::__construct( 'blockedtitle', array_shift( $params ), $params );
486 * Shows a generic "user is not logged in" error page.
488 * This is essentially an ErrorPageError exception which by default uses the
489 * 'exception-nologin' as a title and 'exception-nologin-text' for the message.
495 * if( $user->isAnon() ) {
496 * throw new UserNotLoggedIn();
500 * Note the parameter order differs from ErrorPageError, this allows you to
501 * simply specify a reason without overriding the default title.
505 * if( $user->isAnon() ) {
506 * throw new UserNotLoggedIn( 'action-require-loggedin' );
512 class UserNotLoggedIn
extends ErrorPageError
{
515 * @param $reasonMsg A message key containing the reason for the error.
516 * Optional, default: 'exception-nologin-text'
517 * @param $titleMsg A message key to set the page title.
518 * Optional, default: 'exception-nologin'
519 * @param $params Parameters to wfMessage().
520 * Optional, default: null
522 public function __construct(
523 $reasonMsg = 'exception-nologin-text',
524 $titleMsg = 'exception-nologin',
527 parent
::__construct( $titleMsg, $reasonMsg, $params );
532 * Show an error that looks like an HTTP server error.
533 * Replacement for wfHttpError().
538 class HttpError
extends MWException
{
539 private $httpCode, $header, $content;
544 * @param $httpCode Integer: HTTP status code to send to the client
545 * @param string|Message $content content of the message
546 * @param string|Message $header content of the header (\<title\> and \<h1\>)
548 public function __construct( $httpCode, $content, $header = null ) {
549 parent
::__construct( $content );
550 $this->httpCode
= (int)$httpCode;
551 $this->header
= $header;
552 $this->content
= $content;
556 * Returns the HTTP status code supplied to the constructor.
560 public function getStatusCode() {
561 return $this->httpCode
;
565 * Report the HTTP error.
566 * Sends the appropriate HTTP status code and outputs an
567 * HTML page with an error message.
569 public function report() {
570 $httpMessage = HttpStatus
::getMessage( $this->httpCode
);
572 header( "Status: {$this->httpCode} {$httpMessage}", true, $this->httpCode
);
573 header( 'Content-type: text/html; charset=utf-8' );
575 print $this->getHTML();
579 * Returns HTML for reporting the HTTP error.
580 * This will be a minimal but complete HTML document.
582 * @return string HTML
584 public function getHTML() {
585 if ( $this->header
=== null ) {
586 $header = HttpStatus
::getMessage( $this->httpCode
);
587 } elseif ( $this->header
instanceof Message
) {
588 $header = $this->header
->escaped();
590 $header = htmlspecialchars( $this->header
);
593 if ( $this->content
instanceof Message
) {
594 $content = $this->content
->escaped();
596 $content = htmlspecialchars( $this->content
);
599 return "<!DOCTYPE html>\n" .
600 "<html><head><title>$header</title></head>\n" .
601 "<body><h1>$header</h1><p>$content</p></body></html>\n";
606 * Handler class for MWExceptions
609 class MWExceptionHandler
{
611 * Install an exception handler for MediaWiki exception types.
613 public static function installHandler() {
614 set_exception_handler( array( 'MWExceptionHandler', 'handle' ) );
618 * Report an exception to the user
620 protected static function report( Exception
$e ) {
621 global $wgShowExceptionDetails;
623 $cmdLine = MWException
::isCommandLine();
625 if ( $e instanceof MWException
) {
627 // Try and show the exception prettily, with the normal skin infrastructure
629 } catch ( Exception
$e2 ) {
630 // Exception occurred from within exception handler
631 // Show a simpler error message for the original exception,
632 // don't try to invoke report()
633 $message = "MediaWiki internal error.\n\n";
635 if ( $wgShowExceptionDetails ) {
636 $message .= 'Original exception: ' . self
::formatRedactedTrace( $e ) . "\n\n" .
637 'Exception caught inside exception handler: ' . $e2->__toString();
639 $message .= "Exception caught inside exception handler.\n\n" .
640 "Set \$wgShowExceptionDetails = true; at the bottom of LocalSettings.php " .
641 "to show detailed debugging information.";
647 self
::printError( $message );
649 echo nl2br( htmlspecialchars( $message ) ) . "\n";
653 $message = "Unexpected non-MediaWiki exception encountered, of type \"" . get_class( $e ) . "\"";
655 if ( $wgShowExceptionDetails ) {
656 $message .= "\nexception '" . get_class( $e ) . "' in " . $e->getFile() . ":" . $e->getLine() . "\nStack trace:\n" . self
::formatRedactedTrace( $e ) . "\n";
660 self
::printError( $message );
662 echo nl2br( htmlspecialchars( $message ) ) . "\n";
668 * Print a message, if possible to STDERR.
669 * Use this in command line mode only (see isCommandLine)
671 * @param string $message Failure text
673 public static function printError( $message ) {
674 # NOTE: STDERR may not be available, especially if php-cgi is used from the command line (bug #15602).
675 # Try to produce meaningful output anyway. Using echo may corrupt output to STDOUT though.
676 if ( defined( 'STDERR' ) ) {
677 fwrite( STDERR
, $message );
684 * Exception handler which simulates the appropriate catch() handling:
688 * } catch ( MWException $e ) {
690 * } catch ( Exception $e ) {
691 * echo $e->__toString();
694 public static function handle( $e ) {
695 global $wgFullyInitialised;
700 if ( $wgFullyInitialised ) {
702 // uses $wgRequest, hence the $wgFullyInitialised condition
703 wfLogProfilingData();
704 } catch ( Exception
$e ) {
708 // Exit value should be nonzero for the benefit of shell jobs
713 * Get the stack trace from the exception as a string, redacting certain function arguments in the process
714 * @param Exception $e The exception
715 * @return string The stack trace as a string
717 public static function formatRedactedTrace( Exception
$e ) {
718 global $wgRedactedFunctionArguments;
719 $finalExceptionText = '';
721 foreach ( $e->getTrace() as $i => $call ) {
723 if ( isset( $call['class'] ) ) {
724 $checkFor[] = $call['class'] . '::' . $call['function'];
725 foreach ( class_parents( $call['class'] ) as $parent ) {
726 $checkFor[] = $parent . '::' . $call['function'];
729 $checkFor[] = $call['function'];
732 foreach ( $checkFor as $check ) {
733 if ( isset( $wgRedactedFunctionArguments[$check] ) ) {
734 foreach ( (array)$wgRedactedFunctionArguments[$check] as $argNo ) {
735 $call['args'][$argNo] = 'REDACTED';
740 $finalExceptionText .= "#{$i} {$call['file']}({$call['line']}): ";
741 if ( isset( $call['class'] ) ) {
742 $finalExceptionText .= $call['class'] . $call['type'] . $call['function'];
744 $finalExceptionText .= $call['function'];
747 foreach ( $call['args'] as $arg ) {
748 if ( is_object( $arg ) ) {
749 $args[] = 'Object(' . get_class( $arg ) . ')';
750 } elseif( is_array( $arg ) ) {
753 $args[] = var_export( $arg, true );
756 $finalExceptionText .= '(' . implode( ', ', $args ) . ")\n";
758 return $finalExceptionText . '#' . ( $i +
1 ) . ' {main}';