3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16 * http://www.gnu.org/copyleft/gpl.html
21 use Wikimedia\Rdbms\DBConnectionError;
22 use Wikimedia\Rdbms\DBError;
23 use Wikimedia\Rdbms\DBReadOnlyError;
24 use Wikimedia\Rdbms\DBExpectedError;
27 * Class to expose exceptions to the client (API bots, users, admins using CLI scripts)
30 class MWExceptionRenderer {
31 const AS_RAW = 1; // show as text
32 const AS_PRETTY = 2; // show as HTML
35 * @param Exception|Throwable $e Original exception
36 * @param int $mode MWExceptionExposer::AS_* constant
37 * @param Exception|Throwable|null $eNew New exception from attempting to show the first
39 public static function output( $e, $mode, $eNew = null ) {
42 if ( defined( 'MW_API' ) ) {
43 // Unhandled API exception, we can't be sure that format printer is alive
44 self::header( 'MediaWiki-API-Error: internal_api_error_' . get_class( $e ) );
45 wfHttpError( 500, 'Internal Server Error', self::getText( $e ) );
46 } elseif ( self::isCommandLine() ) {
47 self::printError( self::getText( $e ) );
48 } elseif ( $mode === self::AS_PRETTY ) {
49 self::statusHeader( 500 );
50 self::header( "Content-Type: $wgMimeType; charset=utf-8" );
51 if ( $e instanceof DBConnectionError ) {
52 self::reportOutageHTML( $e );
54 self::reportHTML( $e );
57 self::statusHeader( 500 );
58 self::header( "Content-Type: $wgMimeType; charset=utf-8" );
60 $message = "MediaWiki internal error.\n\n";
61 if ( self::showBackTrace( $e ) ) {
62 $message .= 'Original exception: ' .
63 MWExceptionHandler::getLogMessage( $e ) .
64 "\nBacktrace:\n" . MWExceptionHandler::getRedactedTraceAsString( $e ) .
65 "\n\nException caught inside exception handler: " .
66 MWExceptionHandler::getLogMessage( $eNew ) .
67 "\nBacktrace:\n" . MWExceptionHandler::getRedactedTraceAsString( $eNew );
69 $message .= 'Original exception: ' .
70 MWExceptionHandler::getPublicLogMessage( $e );
71 $message .= "\n\nException caught inside exception handler.\n\n" .
72 self::getShowBacktraceError( $e );
76 if ( self::showBackTrace( $e ) ) {
77 $message = MWExceptionHandler::getLogMessage( $e ) .
79 MWExceptionHandler::getRedactedTraceAsString( $e ) . "\n";
81 $message = MWExceptionHandler::getPublicLogMessage( $e );
84 echo nl2br( htmlspecialchars( $message ) ) . "\n";
89 * @param Exception|Throwable $e
90 * @return bool Should the exception use $wgOut to output the error?
92 private static function useOutputPage( $e ) {
93 // Can the extension use the Message class/wfMessage to get i18n-ed messages?
94 foreach ( $e->getTrace() as $frame ) {
95 if ( isset( $frame['class'] ) && $frame['class'] === 'LocalisationCache' ) {
100 // Don't even bother with OutputPage if there's no Title context set,
101 // (e.g. we're in RL code on load.php) - the Skin system (and probably
102 // most of MediaWiki) won't work.
105 !empty( $GLOBALS['wgFullyInitialised'] ) &&
106 !empty( $GLOBALS['wgOut'] ) &&
107 RequestContext::getMain()->getTitle() &&
108 !defined( 'MEDIAWIKI_INSTALL' )
113 * Output the exception report using HTML
115 * @param Exception|Throwable $e
117 private static function reportHTML( $e ) {
118 global $wgOut, $wgSitename;
120 if ( self::useOutputPage( $e ) ) {
121 if ( $e instanceof MWException ) {
122 $wgOut->prepareErrorPage( $e->getPageTitle() );
123 } elseif ( $e instanceof DBReadOnlyError ) {
124 $wgOut->prepareErrorPage( self::msg( 'readonly', 'Database is locked' ) );
125 } elseif ( $e instanceof DBExpectedError ) {
126 $wgOut->prepareErrorPage( self::msg( 'databaseerror', 'Database error' ) );
128 $wgOut->prepareErrorPage( self::msg( 'internalerror', 'Internal error' ) );
131 // Show any custom GUI message before the details
132 if ( $e instanceof MessageSpecifier ) {
133 $wgOut->addHTML( Message::newFromSpecifier( $e )->escaped() );
135 $wgOut->addHTML( self::getHTML( $e ) );
139 self::header( 'Content-Type: text/html; charset=utf-8' );
140 $pageTitle = self::msg( 'internalerror', 'Internal error' );
141 echo "<!DOCTYPE html>\n" .
143 // Mimick OutputPage::setPageTitle behaviour
145 htmlspecialchars( self::msg( 'pagetitle', "$1 - $wgSitename", $pageTitle ) ) .
147 '<style>body { font-family: sans-serif; margin: 0; padding: 0.5em 2em; }</style>' .
150 echo self::getHTML( $e );
152 echo "</body></html>\n";
157 * If $wgShowExceptionDetails is true, return a HTML message with a
158 * backtrace to the error, otherwise show a message to ask to set it to true
159 * to show that information.
161 * @param Exception|Throwable $e
162 * @return string Html to output
164 public static function getHTML( $e ) {
165 if ( self::showBackTrace( $e ) ) {
166 $html = "<div class=\"errorbox mw-content-ltr\"><p>" .
167 nl2br( htmlspecialchars( MWExceptionHandler::getLogMessage( $e ) ) ) .
168 '</p><p>Backtrace:</p><p>' .
169 nl2br( htmlspecialchars( MWExceptionHandler::getRedactedTraceAsString( $e ) ) ) .
172 $logId = WebRequest::getRequestId();
173 $html = "<div class=\"errorbox mw-content-ltr\">" .
175 '[' . $logId . '] ' .
176 gmdate( 'Y-m-d H:i:s' ) . ": " .
177 self::msg( "internalerror-fatal-exception",
178 "Fatal exception of type $1",
181 MWExceptionHandler::getURL()
184 "<!-- " . wordwrap( self::getShowBacktraceError( $e ), 50 ) . " -->";
191 * Get a message from i18n
193 * @param string $key Message name
194 * @param string $fallback Default message if the message cache can't be
195 * called by the exception
196 * The function also has other parameters that are arguments for the message
197 * @return string Message with arguments replaced
199 private static function msg( $key, $fallback /*[, params...] */ ) {
200 $args = array_slice( func_get_args(), 2 );
202 return wfMessage( $key, $args )->text();
203 } catch ( Exception $e ) {
204 return wfMsgReplaceArgs( $fallback, $args );
209 * @param Exception|Throwable $e
212 private static function getText( $e ) {
213 if ( self::showBackTrace( $e ) ) {
214 return MWExceptionHandler::getLogMessage( $e ) .
216 MWExceptionHandler::getRedactedTraceAsString( $e ) . "\n";
218 return self::getShowBacktraceError( $e ) . "\n";
223 * @param Exception|Throwable $e
226 private static function showBackTrace( $e ) {
227 global $wgShowExceptionDetails, $wgShowDBErrorBacktrace;
230 $wgShowExceptionDetails &&
231 ( !( $e instanceof DBError ) || $wgShowDBErrorBacktrace )
236 * @param Exception|Throwable $e
239 private static function getShowBacktraceError( $e ) {
240 global $wgShowExceptionDetails, $wgShowDBErrorBacktrace;
242 if ( !$wgShowExceptionDetails ) {
243 $vars[] = '$wgShowExceptionDetails = true;';
245 if ( $e instanceof DBError && !$wgShowDBErrorBacktrace ) {
246 $vars[] = '$wgShowDBErrorBacktrace = true;';
248 $vars = implode( ' and ', $vars );
249 return "Set $vars at the bottom of LocalSettings.php to show detailed debugging information.";
255 private static function isCommandLine() {
256 return !empty( $GLOBALS['wgCommandLineMode'] );
260 * @param string $header
262 private static function header( $header ) {
263 if ( !headers_sent() ) {
271 private static function statusHeader( $code ) {
272 if ( !headers_sent() ) {
273 HttpStatus::header( $code );
278 * Print a message, if possible to STDERR.
279 * Use this in command line mode only (see isCommandLine)
281 * @param string $message Failure text
283 private static function printError( $message ) {
284 // NOTE: STDERR may not be available, especially if php-cgi is used from the
285 // command line (bug #15602). Try to produce meaningful output anyway. Using
286 // echo may corrupt output to STDOUT though.
287 if ( defined( 'STDERR' ) ) {
288 fwrite( STDERR, $message );
295 * @param Exception|Throwable $e
297 private static function reportOutageHTML( $e ) {
298 global $wgShowDBErrorBacktrace, $wgShowHostnames, $wgShowSQLErrors, $wgSitename;
300 $sorry = htmlspecialchars( self::msg(
302 'Sorry! This site is experiencing technical difficulties.'
304 $again = htmlspecialchars( self::msg(
306 'Try waiting a few minutes and reloading.'
309 if ( $wgShowHostnames || $wgShowSQLErrors ) {
312 Html::element( 'span', [ 'dir' => 'ltr' ], $e->getMessage() ),
313 htmlspecialchars( self::msg( 'dberr-info', '($1)' ) )
316 $info = htmlspecialchars( self::msg(
318 '(Cannot access the database)'
322 MessageCache::singleton()->disable(); // no DB access
323 $html = "<!DOCTYPE html>\n" .
326 htmlspecialchars( $wgSitename ) .
328 '<style>body { font-family: sans-serif; margin: 0; padding: 0.5em 2em; }</style>' .
329 "</head><body><h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
331 if ( $wgShowDBErrorBacktrace ) {
332 $html .= '<p>Backtrace:</p><pre>' .
333 htmlspecialchars( $e->getTraceAsString() ) . '</pre>';
336 $html .= '</body></html>';