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\DBReadOnlyError
;
23 use Wikimedia\Rdbms\DBExpectedError
;
26 * Class to expose exceptions to the client (API bots, users, admins using CLI scripts)
29 class MWExceptionRenderer
{
30 const AS_RAW
= 1; // show as text
31 const AS_PRETTY
= 2; // show as HTML
34 * @param Exception|Throwable $e Original exception
35 * @param int $mode MWExceptionExposer::AS_* constant
36 * @param Exception|Throwable|null $eNew New exception from attempting to show the first
38 public static function output( $e, $mode, $eNew = null ) {
39 global $wgMimeType, $wgShowExceptionDetails;
41 if ( defined( 'MW_API' ) ) {
42 // Unhandled API exception, we can't be sure that format printer is alive
43 self
::header( 'MediaWiki-API-Error: internal_api_error_' . get_class( $e ) );
44 wfHttpError( 500, 'Internal Server Error', self
::getText( $e ) );
45 } elseif ( self
::isCommandLine() ) {
46 self
::printError( self
::getText( $e ) );
47 } elseif ( $mode === self
::AS_PRETTY
) {
48 self
::statusHeader( 500 );
49 self
::header( "Content-Type: $wgMimeType; charset=utf-8" );
50 if ( $e instanceof DBConnectionError
) {
51 self
::reportOutageHTML( $e );
53 self
::reportHTML( $e );
56 self
::statusHeader( 500 );
57 self
::header( "Content-Type: $wgMimeType; charset=utf-8" );
59 $message = "MediaWiki internal error.\n\n";
60 if ( $wgShowExceptionDetails ) {
61 $message .= 'Original exception: ' .
62 MWExceptionHandler
::getLogMessage( $e ) .
63 "\nBacktrace:\n" . MWExceptionHandler
::getRedactedTraceAsString( $e ) .
64 "\n\nException caught inside exception handler: " .
65 MWExceptionHandler
::getLogMessage( $eNew ) .
66 "\nBacktrace:\n" . MWExceptionHandler
::getRedactedTraceAsString( $eNew );
68 $message .= 'Original exception: ' .
69 MWExceptionHandler
::getPublicLogMessage( $e );
70 $message .= "\n\nException caught inside exception handler.\n\n" .
71 self
::getShowBacktraceError( $e );
74 } elseif ( $wgShowExceptionDetails ) {
75 $message = MWExceptionHandler
::getLogMessage( $e ) .
77 MWExceptionHandler
::getRedactedTraceAsString( $e ) . "\n";
79 $message = MWExceptionHandler
::getPublicLogMessage( $e );
81 echo nl2br( htmlspecialchars( $message ) ) . "\n";
86 * @param Exception|Throwable $e
87 * @return bool Should the exception use $wgOut to output the error?
89 private static function useOutputPage( $e ) {
90 // Can the extension use the Message class/wfMessage to get i18n-ed messages?
91 foreach ( $e->getTrace() as $frame ) {
92 if ( isset( $frame['class'] ) && $frame['class'] === LocalisationCache
::class ) {
97 // Don't even bother with OutputPage if there's no Title context set,
98 // (e.g. we're in RL code on load.php) - the Skin system (and probably
99 // most of MediaWiki) won't work.
102 !empty( $GLOBALS['wgFullyInitialised'] ) &&
103 !empty( $GLOBALS['wgOut'] ) &&
104 RequestContext
::getMain()->getTitle() &&
105 !defined( 'MEDIAWIKI_INSTALL' )
110 * Output the exception report using HTML
112 * @param Exception|Throwable $e
114 private static function reportHTML( $e ) {
115 global $wgOut, $wgSitename;
117 if ( self
::useOutputPage( $e ) ) {
118 if ( $e instanceof MWException
) {
119 $wgOut->prepareErrorPage( $e->getPageTitle() );
120 } elseif ( $e instanceof DBReadOnlyError
) {
121 $wgOut->prepareErrorPage( self
::msg( 'readonly', 'Database is locked' ) );
122 } elseif ( $e instanceof DBExpectedError
) {
123 $wgOut->prepareErrorPage( self
::msg( 'databaseerror', 'Database error' ) );
125 $wgOut->prepareErrorPage( self
::msg( 'internalerror', 'Internal error' ) );
128 // Show any custom GUI message before the details
129 if ( $e instanceof MessageSpecifier
) {
130 $wgOut->addHTML( Html
::element( 'p', [], Message
::newFromSpecifier( $e )->text() ) );
132 $wgOut->addHTML( self
::getHTML( $e ) );
136 self
::header( 'Content-Type: text/html; charset=utf-8' );
137 $pageTitle = self
::msg( 'internalerror', 'Internal error' );
138 echo "<!DOCTYPE html>\n" .
140 // Mimick OutputPage::setPageTitle behaviour
142 htmlspecialchars( self
::msg( 'pagetitle', "$1 - $wgSitename", $pageTitle ) ) .
144 '<style>body { font-family: sans-serif; margin: 0; padding: 0.5em 2em; }</style>' .
147 echo self
::getHTML( $e );
149 echo "</body></html>\n";
154 * If $wgShowExceptionDetails is true, return a HTML message with a
155 * backtrace to the error, otherwise show a message to ask to set it to true
156 * to show that information.
158 * @param Exception|Throwable $e
159 * @return string Html to output
161 public static function getHTML( $e ) {
162 global $wgShowExceptionDetails;
164 if ( $wgShowExceptionDetails ) {
165 $html = "<div class=\"errorbox mw-content-ltr\"><p>" .
166 nl2br( htmlspecialchars( MWExceptionHandler
::getLogMessage( $e ) ) ) .
167 '</p><p>Backtrace:</p><p>' .
168 nl2br( htmlspecialchars( MWExceptionHandler
::getRedactedTraceAsString( $e ) ) ) .
171 $logId = WebRequest
::getRequestId();
172 $html = "<div class=\"errorbox mw-content-ltr\">" .
174 '[' . $logId . '] ' .
175 gmdate( 'Y-m-d H:i:s' ) . ": " .
176 self
::msg( "internalerror-fatal-exception",
177 "Fatal exception of type $1",
180 MWExceptionHandler
::getURL()
182 "<!-- " . wordwrap( self
::getShowBacktraceError( $e ), 50 ) . " -->";
189 * Get a message from i18n
191 * @param string $key Message name
192 * @param string $fallback Default message if the message cache can't be
193 * called by the exception
194 * @param mixed ...$params To pass to wfMessage()
195 * @return string Message with arguments replaced
197 private static function msg( $key, $fallback, ...$params ) {
200 // FIXME: Keep logic in sync with MWException::msg.
202 $res = wfMessage( $key, $params )->text();
203 } catch ( Exception
$e ) {
204 $res = wfMsgReplaceArgs( $fallback, $params );
205 // If an exception happens inside message rendering,
206 // {{SITENAME}} sometimes won't be replaced.
207 $res = strtr( $res, [
208 '{{SITENAME}}' => $wgSitename,
215 * @param Exception|Throwable $e
218 private static function getText( $e ) {
219 global $wgShowExceptionDetails;
221 if ( $wgShowExceptionDetails ) {
222 return MWExceptionHandler
::getLogMessage( $e ) .
224 MWExceptionHandler
::getRedactedTraceAsString( $e ) . "\n";
226 return self
::getShowBacktraceError( $e ) . "\n";
231 * @param Exception|Throwable $e
234 private static function getShowBacktraceError( $e ) {
235 $var = '$wgShowExceptionDetails = true;';
236 return "Set $var at the bottom of LocalSettings.php to show detailed debugging information.";
242 private static function isCommandLine() {
243 return !empty( $GLOBALS['wgCommandLineMode'] );
247 * @param string $header
249 private static function header( $header ) {
250 if ( !headers_sent() ) {
258 private static function statusHeader( $code ) {
259 if ( !headers_sent() ) {
260 HttpStatus
::header( $code );
265 * Print a message, if possible to STDERR.
266 * Use this in command line mode only (see isCommandLine)
268 * @suppress SecurityCheck-XSS
269 * @param string $message Failure text
271 private static function printError( $message ) {
272 // NOTE: STDERR may not be available, especially if php-cgi is used from the
273 // command line (T17602). Try to produce meaningful output anyway. Using
274 // echo may corrupt output to STDOUT though.
275 if ( defined( 'STDERR' ) ) {
276 fwrite( STDERR
, $message );
283 * @param Exception|Throwable $e
285 private static function reportOutageHTML( $e ) {
286 global $wgShowExceptionDetails, $wgShowHostnames, $wgSitename;
288 $sorry = htmlspecialchars( self
::msg(
290 'Sorry! This site is experiencing technical difficulties.'
292 $again = htmlspecialchars( self
::msg(
294 'Try waiting a few minutes and reloading.'
297 if ( $wgShowHostnames ) {
300 Html
::element( 'span', [ 'dir' => 'ltr' ], $e->getMessage() ),
301 htmlspecialchars( self
::msg( 'dberr-info', '($1)' ) )
304 $info = htmlspecialchars( self
::msg(
306 '(Cannot access the database)'
310 MessageCache
::singleton()->disable(); // no DB access
311 $html = "<!DOCTYPE html>\n" .
314 htmlspecialchars( $wgSitename ) .
316 '<style>body { font-family: sans-serif; margin: 0; padding: 0.5em 2em; }</style>' .
317 "</head><body><h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
319 if ( $wgShowExceptionDetails ) {
320 $html .= '<p>Backtrace:</p><pre>' .
321 htmlspecialchars( $e->getTraceAsString() ) . '</pre>';
324 $html .= '</body></html>';