includes/exception/MWExceptionHandler.php

   1 <?php
   2 /**
   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.
   7  *
   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.
  12  *
  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
  17  *
  18  * @file
  19  */
  20
  21 use MediaWiki\Logger\LoggerFactory;
  22 use MediaWiki\MediaWikiServices;
  23 use Psr\Log\LogLevel;
  24 use Wikimedia\Rdbms\DBError;
  25
  26 /**
  27  * Handler class for MWExceptions
  28  * @ingroup Exception
  29  */
  30 class MWExceptionHandler {
  31         const CAUGHT_BY_HANDLER = 'mwe_handler'; // error reported by this exception handler
  32         const CAUGHT_BY_OTHER = 'other'; // error reported by direct logException() call
  33
  34         /**
  35          * @var string $reservedMemory
  36          */
  37         protected static $reservedMemory;
  38         /**
  39          * @var array $fatalErrorTypes
  40          */
  41         protected static $fatalErrorTypes = [
  42                 E_ERROR, E_PARSE, E_CORE_ERROR, E_COMPILE_ERROR, E_USER_ERROR,
  43                 /* HHVM's FATAL_ERROR level */ 16777217,
  44         ];
  45         /**
  46          * @var bool $handledFatalCallback
  47          */
  48         protected static $handledFatalCallback = false;
  49
  50         /**
  51          * Install handlers with PHP.
  52          */
  53         public static function installHandler() {
  54                 set_exception_handler( 'MWExceptionHandler::handleUncaughtException' );
  55                 set_error_handler( 'MWExceptionHandler::handleError' );
  56
  57                 // Reserve 16k of memory so we can report OOM fatals
  58                 self::$reservedMemory = str_repeat( ' ', 16384 );
  59                 register_shutdown_function( 'MWExceptionHandler::handleFatalError' );
  60         }
  61
  62         /**
  63          * Report an exception to the user
  64          * @param Exception|Throwable $e
  65          */
  66         protected static function report( $e ) {
  67                 try {
  68                         // Try and show the exception prettily, with the normal skin infrastructure
  69                         if ( $e instanceof MWException ) {
  70                                 // Delegate to MWException until all subclasses are handled by
  71                                 // MWExceptionRenderer and MWException::report() has been
  72                                 // removed.
  73                                 $e->report();
  74                         } else {
  75                                 MWExceptionRenderer::output( $e, MWExceptionRenderer::AS_PRETTY );
  76                         }
  77                 } catch ( Exception $e2 ) {
  78                         // Exception occurred from within exception handler
  79                         // Show a simpler message for the original exception,
  80                         // don't try to invoke report()
  81                         MWExceptionRenderer::output( $e, MWExceptionRenderer::AS_RAW, $e2 );
  82                 }
  83         }
  84
  85         /**
  86          * Roll back any open database transactions and log the stack trace of the exception
  87          *
  88          * This method is used to attempt to recover from exceptions
  89          *
  90          * @since 1.23
  91          * @param Exception|Throwable $e
  92          */
  93         public static function rollbackMasterChangesAndLog( $e ) {
  94                 $services = MediaWikiServices::getInstance();
  95                 if ( !$services->isServiceDisabled( 'DBLoadBalancerFactory' ) ) {
  96                         // Rollback DBs to avoid transaction notices. This might fail
  97                         // to rollback some databases due to connection issues or exceptions.
  98                         // However, any sane DB driver will rollback implicitly anyway.
  99                         try {
 100                                 $services->getDBLoadBalancerFactory()->rollbackMasterChanges( __METHOD__ );
 101                         } catch ( DBError $e2 ) {
 102                                 // If the DB is unreacheable, rollback() will throw an error
 103                                 // and the error report() method might need messages from the DB,
 104                                 // which would result in an exception loop. PHP may escalate such
 105                                 // errors to "Exception thrown without a stack frame" fatals, but
 106                                 // it's better to be explicit here.
 107                                 self::logException( $e2, self::CAUGHT_BY_HANDLER );
 108                         }
 109                 }
 110
 111                 self::logException( $e, self::CAUGHT_BY_HANDLER );
 112         }
 113
 114         /**
 115          * Callback to use with PHP's set_exception_handler.
 116          *
 117          * @since 1.31
 118          * @param Exception|Throwable $e
 119          */
 120         public static function handleUncaughtException( $e ) {
 121                 self::handleException( $e );
 122
 123                 // Make sure we don't claim success on exit for CLI scripts (T177414)
 124                 if ( wfIsCLI() ) {
 125                         register_shutdown_function(
 126                                 function () {
 127                                         exit( 255 );
 128                                 }
 129                         );
 130                 }
 131         }
 132
 133         /**
 134          * Exception handler which simulates the appropriate catch() handling:
 135          *
 136          *   try {
 137          *       ...
 138          *   } catch ( Exception $e ) {
 139          *       $e->report();
 140          *   } catch ( Exception $e ) {
 141          *       echo $e->__toString();
 142          *   }
 143          *
 144          * @since 1.25
 145          * @param Exception|Throwable $e
 146          */
 147         public static function handleException( $e ) {
 148                 self::rollbackMasterChangesAndLog( $e );
 149                 self::report( $e );
 150         }
 151
 152         /**
 153          * Handler for set_error_handler() callback notifications.
 154          *
 155          * Receive a callback from the interpreter for a raised error, create an
 156          * ErrorException, and log the exception to the 'error' logging
 157          * channel(s). If the raised error is a fatal error type (only under HHVM)
 158          * delegate to handleFatalError() instead.
 159          *
 160          * @since 1.25
 161          *
 162          * @param int $level Error level raised
 163          * @param string $message
 164          * @param string $file
 165          * @param int $line
 166          * @return bool
 167          *
 168          * @see logError()
 169          */
 170         public static function handleError(
 171                 $level, $message, $file = null, $line = null
 172         ) {
 173                 global $wgPropagateErrors;
 174
 175                 if ( in_array( $level, self::$fatalErrorTypes ) ) {
 176                         return call_user_func_array(
 177                                 'MWExceptionHandler::handleFatalError', func_get_args()
 178                         );
 179                 }
 180
 181                 // Map error constant to error name (reverse-engineer PHP error
 182                 // reporting)
 183                 switch ( $level ) {
 184                         case E_RECOVERABLE_ERROR:
 185                                 $levelName = 'Error';
 186                                 $severity = LogLevel::ERROR;
 187                                 break;
 188                         case E_WARNING:
 189                         case E_CORE_WARNING:
 190                         case E_COMPILE_WARNING:
 191                         case E_USER_WARNING:
 192                                 $levelName = 'Warning';
 193                                 $severity = LogLevel::WARNING;
 194                                 break;
 195                         case E_NOTICE:
 196                         case E_USER_NOTICE:
 197                                 $levelName = 'Notice';
 198                                 $severity = LogLevel::INFO;
 199                                 break;
 200                         case E_STRICT:
 201                                 $levelName = 'Strict Standards';
 202                                 $severity = LogLevel::DEBUG;
 203                                 break;
 204                         case E_DEPRECATED:
 205                         case E_USER_DEPRECATED:
 206                                 $levelName = 'Deprecated';
 207                                 $severity = LogLevel::INFO;
 208                                 break;
 209                         default:
 210                                 $levelName = 'Unknown error';
 211                                 $severity = LogLevel::ERROR;
 212                                 break;
 213                 }
 214
 215                 $e = new ErrorException( "PHP $levelName: $message", 0, $level, $file, $line );
 216                 self::logError( $e, 'error', $severity );
 217
 218                 // If $wgPropagateErrors is true return false so PHP shows/logs the error normally.
 219                 // Ignore $wgPropagateErrors if the error should break execution, or track_errors is set
 220                 // (which means someone is counting on regular PHP error handling behavior).
 221                 return !( $wgPropagateErrors || $level == E_RECOVERABLE_ERROR || ini_get( 'track_errors' ) );
 222         }
 223
 224         /**
 225          * Dual purpose callback used as both a set_error_handler() callback and
 226          * a registered shutdown function. Receive a callback from the interpreter
 227          * for a raised error or system shutdown, check for a fatal error, and log
 228          * to the 'fatal' logging channel.
 229          *
 230          * Special handling is included for missing class errors as they may
 231          * indicate that the user needs to install 3rd-party libraries via
 232          * Composer or other means.
 233          *
 234          * @since 1.25
 235          *
 236          * @param int $level Error level raised
 237          * @param string $message Error message
 238          * @param string $file File that error was raised in
 239          * @param int $line Line number error was raised at
 240          * @param array $context Active symbol table point of error
 241          * @param array $trace Backtrace at point of error (undocumented HHVM
 242          *     feature)
 243          * @return bool Always returns false
 244          */
 245         public static function handleFatalError(
 246                 $level = null, $message = null, $file = null, $line = null,
 247                 $context = null, $trace = null
 248         ) {
 249                 // Free reserved memory so that we have space to process OOM
 250                 // errors
 251                 self::$reservedMemory = null;
 252
 253                 if ( $level === null ) {
 254                         // Called as a shutdown handler, get data from error_get_last()
 255                         if ( static::$handledFatalCallback ) {
 256                                 // Already called once (probably as an error handler callback
 257                                 // under HHVM) so don't log again.
 258                                 return false;
 259                         }
 260
 261                         $lastError = error_get_last();
 262                         if ( $lastError !== null ) {
 263                                 $level = $lastError['type'];
 264                                 $message = $lastError['message'];
 265                                 $file = $lastError['file'];
 266                                 $line = $lastError['line'];
 267                         } else {
 268                                 $level = 0;
 269                                 $message = '';
 270                         }
 271                 }
 272
 273                 if ( !in_array( $level, self::$fatalErrorTypes ) ) {
 274                         // Only interested in fatal errors, others should have been
 275                         // handled by MWExceptionHandler::handleError
 276                         return false;
 277                 }
 278
 279                 $msg = "[{exception_id}] PHP Fatal Error: {$message}";
 280
 281                 // Look at message to see if this is a class not found failure
 282                 // HHVM: Class undefined: foo
 283                 // PHP5: Class 'foo' not found
 284                 if ( preg_match( "/Class (undefined: \w+|'\w+' not found)/", $msg ) ) {
 285                         // phpcs:disable Generic.Files.LineLength
 286                         $msg = <<<TXT
 287 {$msg}
 288
 289 MediaWiki or an installed extension requires this class but it is not embedded directly in MediaWiki's git repository and must be installed separately by the end user.
 290
 291 Please see <a href="https://www.mediawiki.org/wiki/Download_from_Git#Fetch_external_libraries">mediawiki.org</a> for help on installing the required components.
 292 TXT;
 293                         // phpcs:enable
 294                 }
 295
 296                 // We can't just create an exception and log it as it is likely that
 297                 // the interpreter has unwound the stack already. If that is true the
 298                 // stacktrace we would get would be functionally empty. If however we
 299                 // have been called as an error handler callback *and* HHVM is in use
 300                 // we will have been provided with a useful stacktrace that we can
 301                 // log.
 302                 $trace = $trace ?: debug_backtrace();
 303                 $logger = LoggerFactory::getInstance( 'fatal' );
 304                 $logger->error( $msg, [
 305                         'fatal_exception' => [
 306                                 'class' => ErrorException::class,
 307                                 'message' => "PHP Fatal Error: {$message}",
 308                                 'code' => $level,
 309                                 'file' => $file,
 310                                 'line' => $line,
 311                                 'trace' => static::redactTrace( $trace ),
 312                         ],
 313                         'exception_id' => wfRandomString( 8 ),
 314                         'caught_by' => self::CAUGHT_BY_HANDLER
 315                 ] );
 316
 317                 // Remember call so we don't double process via HHVM's fatal
 318                 // notifications and the shutdown hook behavior
 319                 static::$handledFatalCallback = true;
 320                 return false;
 321         }
 322
 323         /**
 324          * Generate a string representation of an exception's stack trace
 325          *
 326          * Like Exception::getTraceAsString, but replaces argument values with
 327          * argument type or class name.
 328          *
 329          * @param Exception|Throwable $e
 330          * @return string
 331          * @see prettyPrintTrace()
 332          */
 333         public static function getRedactedTraceAsString( $e ) {
 334                 return self::prettyPrintTrace( self::getRedactedTrace( $e ) );
 335         }
 336
 337         /**
 338          * Generate a string representation of a stacktrace.
 339          *
 340          * @param array $trace
 341          * @param string $pad Constant padding to add to each line of trace
 342          * @return string
 343          * @since 1.26
 344          */
 345         public static function prettyPrintTrace( array $trace, $pad = '' ) {
 346                 $text = '';
 347
 348                 $level = 0;
 349                 foreach ( $trace as $level => $frame ) {
 350                         if ( isset( $frame['file'] ) && isset( $frame['line'] ) ) {
 351                                 $text .= "{$pad}#{$level} {$frame['file']}({$frame['line']}): ";
 352                         } else {
 353                                 // 'file' and 'line' are unset for calls via call_user_func
 354                                 // (T57634) This matches behaviour of
 355                                 // Exception::getTraceAsString to instead display "[internal
 356                                 // function]".
 357                                 $text .= "{$pad}#{$level} [internal function]: ";
 358                         }
 359
 360                         if ( isset( $frame['class'] ) && isset( $frame['type'] ) && isset( $frame['function'] ) ) {
 361                                 $text .= $frame['class'] . $frame['type'] . $frame['function'];
 362                         } elseif ( isset( $frame['function'] ) ) {
 363                                 $text .= $frame['function'];
 364                         } else {
 365                                 $text .= 'NO_FUNCTION_GIVEN';
 366                         }
 367
 368                         if ( isset( $frame['args'] ) ) {
 369                                 $text .= '(' . implode( ', ', $frame['args'] ) . ")\n";
 370                         } else {
 371                                 $text .= "()\n";
 372                         }
 373                 }
 374
 375                 $level = $level + 1;
 376                 $text .= "{$pad}#{$level} {main}";
 377
 378                 return $text;
 379         }
 380
 381         /**
 382          * Return a copy of an exception's backtrace as an array.
 383          *
 384          * Like Exception::getTrace, but replaces each element in each frame's
 385          * argument array with the name of its class (if the element is an object)
 386          * or its type (if the element is a PHP primitive).
 387          *
 388          * @since 1.22
 389          * @param Exception|Throwable $e
 390          * @return array
 391          */
 392         public static function getRedactedTrace( $e ) {
 393                 return static::redactTrace( $e->getTrace() );
 394         }
 395
 396         /**
 397          * Redact a stacktrace generated by Exception::getTrace(),
 398          * debug_backtrace() or similar means. Replaces each element in each
 399          * frame's argument array with the name of its class (if the element is an
 400          * object) or its type (if the element is a PHP primitive).
 401          *
 402          * @since 1.26
 403          * @param array $trace Stacktrace
 404          * @return array Stacktrace with arugment values converted to data types
 405          */
 406         public static function redactTrace( array $trace ) {
 407                 return array_map( function ( $frame ) {
 408                         if ( isset( $frame['args'] ) ) {
 409                                 $frame['args'] = array_map( function ( $arg ) {
 410                                         return is_object( $arg ) ? get_class( $arg ) : gettype( $arg );
 411                                 }, $frame['args'] );
 412                         }
 413                         return $frame;
 414                 }, $trace );
 415         }
 416
 417         /**
 418          * Get the ID for this exception.
 419          *
 420          * The ID is saved so that one can match the one output to the user (when
 421          * $wgShowExceptionDetails is set to false), to the entry in the debug log.
 422          *
 423          * @since 1.22
 424          * @deprecated since 1.27: Exception IDs are synonymous with request IDs.
 425          * @param Exception|Throwable $e
 426          * @return string
 427          */
 428         public static function getLogId( $e ) {
 429                 wfDeprecated( __METHOD__, '1.27' );
 430                 return WebRequest::getRequestId();
 431         }
 432
 433         /**
 434          * If the exception occurred in the course of responding to a request,
 435          * returns the requested URL. Otherwise, returns false.
 436          *
 437          * @since 1.23
 438          * @return string|false
 439          */
 440         public static function getURL() {
 441                 global $wgRequest;
 442                 if ( !isset( $wgRequest ) || $wgRequest instanceof FauxRequest ) {
 443                         return false;
 444                 }
 445                 return $wgRequest->getRequestURL();
 446         }
 447
 448         /**
 449          * Get a message formatting the exception message and its origin.
 450          *
 451          * @since 1.22
 452          * @param Exception|Throwable $e
 453          * @return string
 454          */
 455         public static function getLogMessage( $e ) {
 456                 $id = WebRequest::getRequestId();
 457                 $type = get_class( $e );
 458                 $file = $e->getFile();
 459                 $line = $e->getLine();
 460                 $message = $e->getMessage();
 461                 $url = self::getURL() ?: '[no req]';
 462
 463                 return "[$id] $url   $type from line $line of $file: $message";
 464         }
 465
 466         /**
 467          * Get a normalised message for formatting with PSR-3 log event context.
 468          *
 469          * Must be used together with `getLogContext()` to be useful.
 470          *
 471          * @since 1.30
 472          * @param Exception|Throwable $e
 473          * @return string
 474          */
 475         public static function getLogNormalMessage( $e ) {
 476                 $type = get_class( $e );
 477                 $file = $e->getFile();
 478                 $line = $e->getLine();
 479                 $message = $e->getMessage();
 480
 481                 return "[{exception_id}] {exception_url}   $type from line $line of $file: $message";
 482         }
 483
 484         /**
 485          * @param Exception|Throwable $e
 486          * @return string
 487          */
 488         public static function getPublicLogMessage( $e ) {
 489                 $reqId = WebRequest::getRequestId();
 490                 $type = get_class( $e );
 491                 return '[' . $reqId . '] '
 492                         . gmdate( 'Y-m-d H:i:s' ) . ': '
 493                         . 'Fatal exception of type "' . $type . '"';
 494         }
 495
 496         /**
 497          * Get a PSR-3 log event context from an Exception.
 498          *
 499          * Creates a structured array containing information about the provided
 500          * exception that can be used to augment a log message sent to a PSR-3
 501          * logger.
 502          *
 503          * @param Exception|Throwable $e
 504          * @param string $catcher CAUGHT_BY_* class constant indicating what caught the error
 505          * @return array
 506          */
 507         public static function getLogContext( $e, $catcher = self::CAUGHT_BY_OTHER ) {
 508                 return [
 509                         'exception' => $e,
 510                         'exception_id' => WebRequest::getRequestId(),
 511                         'exception_url' => self::getURL() ?: '[no req]',
 512                         'caught_by' => $catcher
 513                 ];
 514         }
 515
 516         /**
 517          * Get a structured representation of an Exception.
 518          *
 519          * Returns an array of structured data (class, message, code, file,
 520          * backtrace) derived from the given exception. The backtrace information
 521          * will be redacted as per getRedactedTraceAsArray().
 522          *
 523          * @param Exception|Throwable $e
 524          * @param string $catcher CAUGHT_BY_* class constant indicating what caught the error
 525          * @return array
 526          * @since 1.26
 527          */
 528         public static function getStructuredExceptionData( $e, $catcher = self::CAUGHT_BY_OTHER ) {
 529                 global $wgLogExceptionBacktrace;
 530
 531                 $data = [
 532                         'id' => WebRequest::getRequestId(),
 533                         'type' => get_class( $e ),
 534                         'file' => $e->getFile(),
 535                         'line' => $e->getLine(),
 536                         'message' => $e->getMessage(),
 537                         'code' => $e->getCode(),
 538                         'url' => self::getURL() ?: null,
 539                         'caught_by' => $catcher
 540                 ];
 541
 542                 if ( $e instanceof ErrorException &&
 543                         ( error_reporting() & $e->getSeverity() ) === 0
 544                 ) {
 545                         // Flag surpressed errors
 546                         $data['suppressed'] = true;
 547                 }
 548
 549                 if ( $wgLogExceptionBacktrace ) {
 550                         $data['backtrace'] = self::getRedactedTrace( $e );
 551                 }
 552
 553                 $previous = $e->getPrevious();
 554                 if ( $previous !== null ) {
 555                         $data['previous'] = self::getStructuredExceptionData( $previous, $catcher );
 556                 }
 557
 558                 return $data;
 559         }
 560
 561         /**
 562          * Serialize an Exception object to JSON.
 563          *
 564          * The JSON object will have keys 'id', 'file', 'line', 'message', and
 565          * 'url'. These keys map to string values, with the exception of 'line',
 566          * which is a number, and 'url', which may be either a string URL or or
 567          * null if the exception did not occur in the context of serving a web
 568          * request.
 569          *
 570          * If $wgLogExceptionBacktrace is true, it will also have a 'backtrace'
 571          * key, mapped to the array return value of Exception::getTrace, but with
 572          * each element in each frame's "args" array (if set) replaced with the
 573          * argument's class name (if the argument is an object) or type name (if
 574          * the argument is a PHP primitive).
 575          *
 576          * @par Sample JSON record ($wgLogExceptionBacktrace = false):
 577          * @code
 578          *  {
 579          *    "id": "c41fb419",
 580          *    "type": "MWException",
 581          *    "file": "/var/www/mediawiki/includes/cache/MessageCache.php",
 582          *    "line": 704,
 583          *    "message": "Non-string key given",
 584          *    "url": "/wiki/Main_Page"
 585          *  }
 586          * @endcode
 587          *
 588          * @par Sample JSON record ($wgLogExceptionBacktrace = true):
 589          * @code
 590          *  {
 591          *    "id": "dc457938",
 592          *    "type": "MWException",
 593          *    "file": "/vagrant/mediawiki/includes/cache/MessageCache.php",
 594          *    "line": 704,
 595          *    "message": "Non-string key given",
 596          *    "url": "/wiki/Main_Page",
 597          *    "backtrace": [{
 598          *      "file": "/vagrant/mediawiki/extensions/VisualEditor/VisualEditor.hooks.php",
 599          *      "line": 80,
 600          *      "function": "get",
 601          *      "class": "MessageCache",
 602          *      "type": "->",
 603          *      "args": ["array"]
 604          *    }]
 605          *  }
 606          * @endcode
 607          *
 608          * @since 1.23
 609          * @param Exception|Throwable $e
 610          * @param bool $pretty Add non-significant whitespace to improve readability (default: false).
 611          * @param int $escaping Bitfield consisting of FormatJson::.*_OK class constants.
 612          * @param string $catcher CAUGHT_BY_* class constant indicating what caught the error
 613          * @return string|false JSON string if successful; false upon failure
 614          */
 615         public static function jsonSerializeException(
 616                 $e, $pretty = false, $escaping = 0, $catcher = self::CAUGHT_BY_OTHER
 617         ) {
 618                 return FormatJson::encode(
 619                         self::getStructuredExceptionData( $e, $catcher ),
 620                         $pretty,
 621                         $escaping
 622                 );
 623         }
 624
 625         /**
 626          * Log an exception to the exception log (if enabled).
 627          *
 628          * This method must not assume the exception is an MWException,
 629          * it is also used to handle PHP exceptions or exceptions from other libraries.
 630          *
 631          * @since 1.22
 632          * @param Exception|Throwable $e
 633          * @param string $catcher CAUGHT_BY_* class constant indicating what caught the error
 634          */
 635         public static function logException( $e, $catcher = self::CAUGHT_BY_OTHER ) {
 636                 if ( !( $e instanceof MWException ) || $e->isLoggable() ) {
 637                         $logger = LoggerFactory::getInstance( 'exception' );
 638                         $logger->error(
 639                                 self::getLogNormalMessage( $e ),
 640                                 self::getLogContext( $e, $catcher )
 641                         );
 642
 643                         $json = self::jsonSerializeException( $e, false, FormatJson::ALL_OK, $catcher );
 644                         if ( $json !== false ) {
 645                                 $logger = LoggerFactory::getInstance( 'exception-json' );
 646                                 $logger->error( $json, [ 'private' => true ] );
 647                         }
 648
 649                         Hooks::run( 'LogException', [ $e, false ] );
 650                 }
 651         }
 652
 653         /**
 654          * Log an exception that wasn't thrown but made to wrap an error.
 655          *
 656          * @since 1.25
 657          * @param ErrorException $e
 658          * @param string $channel
 659          * @param string $level
 660          */
 661         protected static function logError(
 662                 ErrorException $e, $channel, $level = LogLevel::ERROR
 663         ) {
 664                 $catcher = self::CAUGHT_BY_HANDLER;
 665                 // The set_error_handler callback is independent from error_reporting.
 666                 // Filter out unwanted errors manually (e.g. when
 667                 // MediaWiki\suppressWarnings is active).
 668                 $suppressed = ( error_reporting() & $e->getSeverity() ) === 0;
 669                 if ( !$suppressed ) {
 670                         $logger = LoggerFactory::getInstance( $channel );
 671                         $logger->log(
 672                                 $level,
 673                                 self::getLogNormalMessage( $e ),
 674                                 self::getLogContext( $e, $catcher )
 675                         );
 676                 }
 677
 678                 // Include all errors in the json log (surpressed errors will be flagged)
 679                 $json = self::jsonSerializeException( $e, false, FormatJson::ALL_OK, $catcher );
 680                 if ( $json !== false ) {
 681                         $logger = LoggerFactory::getInstance( "{$channel}-json" );
 682                         $logger->log( $level, $json, [ 'private' => true ] );
 683                 }
 684
 685                 Hooks::run( 'LogException', [ $e, $suppressed ] );
 686         }
 687 }