MediaWiki  REL1_31
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1 <?php
23 use Psr\Log\LogLevel;
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
37  protected static $reservedMemory;
41  protected static $fatalErrorTypes = [
43  /* HHVM's FATAL_ERROR level */ 16777217,
44  ];
48  protected static $handledFatalCallback = false;
53  public static function installHandler() {
54  set_exception_handler( 'MWExceptionHandler::handleUncaughtException' );
55  set_error_handler( 'MWExceptionHandler::handleError' );
57  // Reserve 16k of memory so we can report OOM fatals
58  self::$reservedMemory = str_repeat( ' ', 16384 );
59  register_shutdown_function( 'MWExceptionHandler::handleFatalError' );
60  }
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 {
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()
82  }
83  }
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  }
111  self::logException( $e, self::CAUGHT_BY_HANDLER );
112  }
120  public static function handleUncaughtException( $e ) {
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  }
147  public static function handleException( $e ) {
149  self::report( $e );
150  }
170  public static function handleError(
171  $level, $message, $file = null, $line = null
172  ) {
175  if ( in_array( $level, self::$fatalErrorTypes ) ) {
176  return call_user_func_array(
177  'MWExceptionHandler::handleFatalError', func_get_args()
178  );
179  }
181  // Map error constant to error name (reverse-engineer PHP error
182  // reporting)
183  switch ( $level ) {
185  $levelName = 'Error';
186  $severity = LogLevel::ERROR;
187  break;
188  case E_WARNING:
189  case E_CORE_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:
206  $levelName = 'Deprecated';
207  $severity = LogLevel::INFO;
208  break;
209  default:
210  $levelName = 'Unknown error';
211  $severity = LogLevel::ERROR;
212  break;
213  }
215  $e = new ErrorException( "PHP $levelName: $message", 0, $level, $file, $line );
216  self::logError( $e, 'error', $severity );
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  }
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;
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  }
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  }
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  }
280  $msgParts = [
281  '[{exception_id}] {exception_url} PHP Fatal Error',
282  ( $line || $file ) ? ' from' : '',
283  $line ? " line $line" : '',
284  ( $line && $file ) ? ' of' : '',
285  $file ? " $file" : '',
286  ": $message",
287  ];
288  $msg = implode( '', $msgParts );
290  // Look at message to see if this is a class not found failure
291  // HHVM: Class undefined: foo
292  // PHP5: Class 'foo' not found
293  if ( preg_match( "/Class (undefined: \w+|'\w+' not found)/", $message ) ) {
294  // phpcs:disable Generic.Files.LineLength
295  $msg = <<<TXT
296 {$msg}
298 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.
300 Please see <a href=""></a> for help on installing the required components.
301 TXT;
302  // phpcs:enable
303  }
305  // We can't just create an exception and log it as it is likely that
306  // the interpreter has unwound the stack already. If that is true the
307  // stacktrace we would get would be functionally empty. If however we
308  // have been called as an error handler callback *and* HHVM is in use
309  // we will have been provided with a useful stacktrace that we can
310  // log.
311  $trace = $trace ?: debug_backtrace();
312  $logger = LoggerFactory::getInstance( 'fatal' );
313  $logger->error( $msg, [
314  'fatal_exception' => [
315  'class' => ErrorException::class,
316  'message' => "PHP Fatal Error: {$message}",
317  'code' => $level,
318  'file' => $file,
319  'line' => $line,
320  'trace' => self::prettyPrintTrace( self::redactTrace( $trace ) ),
321  ],
322  'exception_id' => WebRequest::getRequestId(),
323  'exception_url' => $url,
324  'caught_by' => self::CAUGHT_BY_HANDLER
325  ] );
327  // Remember call so we don't double process via HHVM's fatal
328  // notifications and the shutdown hook behavior
329  static::$handledFatalCallback = true;
330  return false;
331  }
343  public static function getRedactedTraceAsString( $e ) {
344  return self::prettyPrintTrace( self::getRedactedTrace( $e ) );
345  }
355  public static function prettyPrintTrace( array $trace, $pad = '' ) {
356  $text = '';
358  $level = 0;
359  foreach ( $trace as $level => $frame ) {
360  if ( isset( $frame['file'] ) && isset( $frame['line'] ) ) {
361  $text .= "{$pad}#{$level} {$frame['file']}({$frame['line']}): ";
362  } else {
363  // 'file' and 'line' are unset for calls via call_user_func
364  // (T57634) This matches behaviour of
365  // Exception::getTraceAsString to instead display "[internal
366  // function]".
367  $text .= "{$pad}#{$level} [internal function]: ";
368  }
370  if ( isset( $frame['class'] ) && isset( $frame['type'] ) && isset( $frame['function'] ) ) {
371  $text .= $frame['class'] . $frame['type'] . $frame['function'];
372  } elseif ( isset( $frame['function'] ) ) {
373  $text .= $frame['function'];
374  } else {
375  $text .= 'NO_FUNCTION_GIVEN';
376  }
378  if ( isset( $frame['args'] ) ) {
379  $text .= '(' . implode( ', ', $frame['args'] ) . ")\n";
380  } else {
381  $text .= "()\n";
382  }
383  }
385  $level = $level + 1;
386  $text .= "{$pad}#{$level} {main}";
388  return $text;
389  }
402  public static function getRedactedTrace( $e ) {
403  return static::redactTrace( $e->getTrace() );
404  }
416  public static function redactTrace( array $trace ) {
417  return array_map( function ( $frame ) {
418  if ( isset( $frame['args'] ) ) {
419  $frame['args'] = array_map( function ( $arg ) {
420  return is_object( $arg ) ? get_class( $arg ) : gettype( $arg );
421  }, $frame['args'] );
422  }
423  return $frame;
424  }, $trace );
425  }
438  public static function getLogId( $e ) {
439  wfDeprecated( __METHOD__, '1.27' );
440  return WebRequest::getRequestId();
441  }
450  public static function getURL() {
452  if ( !isset( $wgRequest ) || $wgRequest instanceof FauxRequest ) {
453  return false;
454  }
455  return $wgRequest->getRequestURL();
456  }
465  public static function getLogMessage( $e ) {
466  $id = WebRequest::getRequestId();
467  $type = get_class( $e );
468  $file = $e->getFile();
469  $line = $e->getLine();
470  $message = $e->getMessage();
471  $url = self::getURL() ?: '[no req]';
473  return "[$id] $url $type from line $line of $file: $message";
474  }
485  public static function getLogNormalMessage( $e ) {
486  $type = get_class( $e );
487  $file = $e->getFile();
488  $line = $e->getLine();
489  $message = $e->getMessage();
491  return "[{exception_id}] {exception_url} $type from line $line of $file: $message";
492  }
498  public static function getPublicLogMessage( $e ) {
499  $reqId = WebRequest::getRequestId();
500  $type = get_class( $e );
501  return '[' . $reqId . '] '
502  . gmdate( 'Y-m-d H:i:s' ) . ': '
503  . 'Fatal exception of type "' . $type . '"';
504  }
517  public static function getLogContext( $e, $catcher = self::CAUGHT_BY_OTHER ) {
518  return [
519  'exception' => $e,
520  'exception_id' => WebRequest::getRequestId(),
521  'exception_url' => self::getURL() ?: '[no req]',
522  'caught_by' => $catcher
523  ];
524  }
538  public static function getStructuredExceptionData( $e, $catcher = self::CAUGHT_BY_OTHER ) {
541  $data = [
542  'id' => WebRequest::getRequestId(),
543  'type' => get_class( $e ),
544  'file' => $e->getFile(),
545  'line' => $e->getLine(),
546  'message' => $e->getMessage(),
547  'code' => $e->getCode(),
548  'url' => self::getURL() ?: null,
549  'caught_by' => $catcher
550  ];
552  if ( $e instanceof ErrorException &&
553  ( error_reporting() & $e->getSeverity() ) === 0
554  ) {
555  // Flag surpressed errors
556  $data['suppressed'] = true;
557  }
559  if ( $wgLogExceptionBacktrace ) {
560  $data['backtrace'] = self::getRedactedTrace( $e );
561  }
563  $previous = $e->getPrevious();
564  if ( $previous !== null ) {
565  $data['previous'] = self::getStructuredExceptionData( $previous, $catcher );
566  }
568  return $data;
569  }
625  public static function jsonSerializeException(
626  $e, $pretty = false, $escaping = 0, $catcher = self::CAUGHT_BY_OTHER
627  ) {
628  return FormatJson::encode(
629  self::getStructuredExceptionData( $e, $catcher ),
630  $pretty,
631  $escaping
632  );
633  }
645  public static function logException( $e, $catcher = self::CAUGHT_BY_OTHER ) {
646  if ( !( $e instanceof MWException ) || $e->isLoggable() ) {
647  $logger = LoggerFactory::getInstance( 'exception' );
648  $logger->error(
649  self::getLogNormalMessage( $e ),
650  self::getLogContext( $e, $catcher )
651  );
653  $json = self::jsonSerializeException( $e, false, FormatJson::ALL_OK, $catcher );
654  if ( $json !== false ) {
655  $logger = LoggerFactory::getInstance( 'exception-json' );
656  $logger->error( $json, [ 'private' => true ] );
657  }
659  Hooks::run( 'LogException', [ $e, false ] );
660  }
661  }
671  protected static function logError(
672  ErrorException $e, $channel, $level = LogLevel::ERROR
673  ) {
674  $catcher = self::CAUGHT_BY_HANDLER;
675  // The set_error_handler callback is independent from error_reporting.
676  // Filter out unwanted errors manually (e.g. when
677  // Wikimedia\suppressWarnings is active).
678  $suppressed = ( error_reporting() & $e->getSeverity() ) === 0;
679  if ( !$suppressed ) {
680  $logger = LoggerFactory::getInstance( $channel );
681  $logger->log(
682  $level,
683  self::getLogNormalMessage( $e ),
684  self::getLogContext( $e, $catcher )
685  );
686  }
688  // Include all errors in the json log (surpressed errors will be flagged)
689  $json = self::jsonSerializeException( $e, false, FormatJson::ALL_OK, $catcher );
690  if ( $json !== false ) {
691  $logger = LoggerFactory::getInstance( "{$channel}-json" );
692  $logger->log( $level, $json, [ 'private' => true ] );
693  }
695  Hooks::run( 'LogException', [ $e, $suppressed ] );
696  }
697 }
static logError(ErrorException $e, $channel, $level=LogLevel::ERROR)
Log an exception that wasn't thrown but made to wrap an error.
Definition: MWExceptionHandler.php:671
static $handledFatalCallback
Definition: MWExceptionHandler.php:48
static getRedactedTrace( $e)
Return a copy of an exception's backtrace as an array.
Definition: MWExceptionHandler.php:402
WebRequest clone which takes values from a provided array.
Definition: FauxRequest.php:33
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
Definition: APACHE-LICENSE-2.0.txt:10
the array() calling protocol came about after MediaWiki 1.4rc1.
We use the convention $dbr for read and $dbw for write to help you keep track of whether the database object is a the world will explode Or to be a subsequent write query which succeeded on the master may fail when replicated to the slave due to a unique key collision Replication on the slave will stop and it may take hours to repair the database and get it back online Setting read_only in my cnf on the slave will avoid this but given the dire we prefer to have as many checks as possible We provide a but the wrapper functions like please read the documentation for except in special pages derived from QueryPage It s a common pitfall for new developers to submit code containing SQL queries which examine huge numbers of rows Remember that COUNT * is(N), counting rows in atable is like counting beans in a bucket.------------------------------------------------------------------------ Replication------------------------------------------------------------------------The largest installation of MediaWiki, Wikimedia, uses a large set ofslave MySQL servers replicating writes made to a master MySQL server. Itis important to understand the issues associated with this setup if youwant to write code destined for Wikipedia.It 's often the case that the best algorithm to use for a given taskdepends on whether or not replication is in use. Due to our unabashedWikipedia-centrism, we often just use the replication-friendly version, but if you like, you can use wfGetLB() ->getServerCount() > 1 tocheck to see if replication is in use.===Lag===Lag primarily occurs when large write queries are sent to the master.Writes on the master are executed in parallel, but they are executed inserial when they are replicated to the slaves. The master writes thequery to the binlog when the transaction is committed. The slaves pollthe binlog and start executing the query as soon as it appears. They canservice reads while they are performing a write query, but will not readanything more from the binlog and thus will perform no more writes. Thismeans that if the write query runs for a long time, the slaves will lagbehind the master for the time it takes for the write query to complete.Lag can be exacerbated by high read load. MediaWiki 's load balancer willstop sending reads to a slave when it is lagged by more than 30 seconds.If the load ratios are set incorrectly, or if there is too much loadgenerally, this may lead to a slave permanently hovering around 30seconds lag.If all slaves are lagged by more than 30 seconds, MediaWiki will stopwriting to the database. All edits and other write operations will berefused, with an error returned to the user. This gives the slaves achance to catch up. Before we had this mechanism, the slaves wouldregularly lag by several minutes, making review of recent editsdifficult.In addition to this, MediaWiki attempts to ensure that the user seesevents occurring on the wiki in chronological order. A few seconds of lagcan be tolerated, as long as the user sees a consistent picture fromsubsequent requests. This is done by saving the master binlog positionin the session, and then at the start of each request, waiting for theslave to catch up to that position before doing any reads from it. Ifthis wait times out, reads are allowed anyway, but the request isconsidered to be in "lagged slave mode". Lagged slave mode can bechecked by calling wfGetLB() ->getLaggedSlaveMode(). The onlypractical consequence at present is a warning displayed in the pagefooter.===Lag avoidance===To avoid excessive lag, queries which write large numbers of rows shouldbe split up, generally to write one row at a time. Multi-row INSERT ...SELECT queries are the worst offenders should be avoided altogether.Instead do the select first and then the insert.===Working with lag===Despite our best efforts, it 's not practical to guarantee a low-lagenvironment. Lag will usually be less than one second, but mayoccasionally be up to 30 seconds. For scalability, it 's very importantto keep load on the master low, so simply sending all your queries tothe master is not the answer. So when you have a genuine need forup-to-date data, the following approach is advised:1) Do a quick query to the master for a sequence number or timestamp 2) Run the full query on the slave and check if it matches the data you gotfrom the master 3) If it doesn 't, run the full query on the masterTo avoid swamping the master every time the slaves lag, use of thisapproach should be kept to a minimum. In most cases you should just readfrom the slave and let the user deal with the delay.------------------------------------------------------------------------ Lock contention------------------------------------------------------------------------Due to the high write rate on Wikipedia(and some other wikis), MediaWiki developers need to be very careful to structure their writesto avoid long-lasting locks. By default, MediaWiki opens a transactionat the first query, and commits it before the output is sent. Locks willbe held from the time when the query is done until the commit. So youcan reduce lock time by doing as much processing as possible before youdo your write queries.Often this approach is not good enough, and it becomes necessary toenclose small groups of queries in their own transaction. Use thefollowing syntax:$dbw=wfGetDB(DB_MASTER
static getLogNormalMessage( $e)
Get a normalised message for formatting with PSR-3 log event context.
Definition: MWExceptionHandler.php:485
static getStructuredExceptionData( $e, $catcher=self::CAUGHT_BY_OTHER)
Get a structured representation of an Exception.
Definition: MWExceptionHandler.php:538
Handler class for MWExceptions.
Definition: MWExceptionHandler.php:30
Definition: MWExceptionHandler.php:31
static redactTrace(array $trace)
Redact a stacktrace generated by Exception::getTrace(), debug_backtrace() or similar means.
Definition: MWExceptionHandler.php:416
static installHandler()
Install handlers with PHP.
Definition: MWExceptionHandler.php:53
static handleUncaughtException( $e)
Callback to use with PHP's set_exception_handler.
Definition: MWExceptionHandler.php:120
Database error base class.
Definition: DBError.php:30
const ALL_OK
Skip escaping as many characters as reasonably possible.
Definition: FormatJson.php:55
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:37
If true, the MediaWiki error handler passes errors/warnings to the default error handler after loggin...
Definition: DefaultSettings.php:6324
static getPublicLogMessage( $e)
Definition: MWExceptionHandler.php:498
static encode( $value, $pretty=false, $escaping=0)
Returns the JSON representation of a value.
Definition: FormatJson.php:127
Definition: MWExceptionHandler.php:32
static handleFatalError( $level=null, $message=null, $file=null, $line=null, $context=null, $trace=null)
Dual purpose callback used as both a set_error_handler() callback and a registered shutdown function.
Definition: MWExceptionHandler.php:245
MediaWiki exception.
Definition: MWException.php:26
static getLogContext( $e, $catcher=self::CAUGHT_BY_OTHER)
Get a PSR-3 log event context from an Exception.
Definition: MWExceptionHandler.php:517
static prettyPrintTrace(array $trace, $pad='')
Generate a string representation of a stacktrace.
Definition: MWExceptionHandler.php:355
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such and we might be restricted by PHP settings such as safe mode or open_basedir We cannot assume that the software even has read access anywhere useful Many shared hosts run all users web applications under the same user
Wikitext formatted, in the key only.
Definition: distributors.txt:25
wfDeprecated( $function, $version=false, $component=false, $callerOffset=2)
Throws a warning that $function is deprecated.
Definition: GlobalFunctions.php:1123
static getURL()
If the exception occurred in the course of responding to a request, returns the requested URL.
Definition: MWExceptionHandler.php:450
static handleException( $e)
Exception handler which simulates the appropriate catch() handling:
Definition: MWExceptionHandler.php:147
static getLogMessage( $e)
Get a message formatting the exception message and its origin.
Definition: MWExceptionHandler.php:465
design txt This is a brief overview of the new design More thorough and up to date information is available on the documentation wiki at etc Handles the details of getting and saving to the user table of the and dealing with sessions and cookies OutputPage Encapsulates the entire HTML page that will be sent in response to any server request It is used by calling its functions to add in any and then calling but I prefer the flexibility This should also do the output encoding The system allocates a global one in $wgOut Title Represents the title of an and does all the work of translating among various forms such as plain database etc For and for historical it also represents a few features of articles that don t involve their such as access rights See also title txt Article Encapsulates access to the page table of the database The object represents a an and maintains state such as etc Revision Encapsulates individual page revision data and access to the revision text blobs storage system Higher level code should never touch text storage directly
Definition: design.txt:39
static $fatalErrorTypes
Definition: MWExceptionHandler.php:41
static rollbackMasterChangesAndLog( $e)
Roll back any open database transactions and log the stack trace of the exception.
Definition: MWExceptionHandler.php:93
A helper class for throttling authentication attempts.
If true, send the exception backtrace to the error log.
Definition: DefaultSettings.php:6318
static $reservedMemory
Definition: MWExceptionHandler.php:37
Definition: MWExceptionRenderer.php:32
when a variable name is used in a it is silently declared as a new masking the global
Definition: design.txt:95
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for and distribution as defined by Sections through of this document Licensor shall mean the copyright owner or entity authorized by the copyright owner that is granting the License Legal Entity shall mean the union of the acting entity and all other entities that control are controlled by or are under common control with that entity For the purposes of this definition control direct or to cause the direction or management of such whether by contract or including but not limited to software source documentation and configuration files Object form shall mean any form resulting from mechanical transformation or translation of a Source including but not limited to compiled object generated and conversions to other media types Work shall mean the work of whether in Source or Object made available under the as indicated by a copyright notice that is included in or attached to the whether in Source or Object that is based or other modifications as a an original work of authorship For the purposes of this Derivative Works shall not include works that remain separable or merely the Work and Derivative Works thereof Contribution shall mean any work of including the original version of the Work and any modifications or additions to that Work or Derivative Works that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner For the purposes of this submitted means any form of or written communication sent to the Licensor or its including but not limited to communication on electronic mailing source code control and issue tracking systems that are managed by
Definition: APACHE-LICENSE-2.0.txt:58
static getLogId( $e)
Get the ID for this exception.
Definition: MWExceptionHandler.php:438
static configuration should be added through ResourceLoaderGetConfigVars instead can be used to get the real title after the basic globals have been set but before ordinary actions take place or wrap services the preferred way to define a new service is the $wgServiceWiringFiles array $services
Definition: hooks.txt:2273
Definition: cdb.php:59
Some information about database access in MediaWiki By Tim January Database layout For information about the MediaWiki database such as a description of the tables and their please see
Definition: database.txt:18
=Architecture==Two class hierarchies are used to provide the functionality associated with the different content models:*Content interface(and AbstractContent base class) define functionality that acts on the concrete content of a page, and *ContentHandler base class provides functionality specific to a content model, but not acting on concrete content. The most important function of ContentHandler is to act as a factory for the appropriate implementation of Content. These Content objects are to be used by MediaWiki everywhere, instead of passing page content around as text. All manipulation and analysis of page content must be done via the appropriate methods of the Content object. For each content model, a subclass of ContentHandler has to be registered with $wgContentHandlers. The ContentHandler object for a given content model can be obtained using ContentHandler::getForModelID($id). Also Title, WikiPage and Revision now have getContentHandler() methods for convenience. ContentHandler objects are singletons that provide functionality specific to the content type, but not directly acting on the content of some page. ContentHandler::makeEmptyContent() and ContentHandler::unserializeContent() can be used to create a Content object of the appropriate type. However, it is recommended to instead use WikiPage::getContent() resp. Revision::getContent() to get a page 's content as a Content object. These two methods should be the ONLY way in which page content is accessed. Another important function of ContentHandler objects is to define custom action handlers for a content model, see ContentHandler::getActionOverrides(). This is similar to what WikiPage::getActionOverrides() was already doing.==Serialization==With the ContentHandler facility, page content no longer has to be text based. Objects implementing the Content interface are used to represent and handle the content internally. For storage and data exchange, each content model supports at least one serialization format via ContentHandler::serializeContent($content). The list of supported formats for a given content model can be accessed using ContentHandler::getSupportedFormats(). Content serialization formats are identified using MIME type like strings. The following formats are built in:*text/x-wiki - wikitext *text/javascript - for js pages *text/css - for css pages *text/plain - for future use, e.g. with plain text messages. *text/html - for future use, e.g. with plain html messages. *application/vnd.php.serialized - for future use with the api and for extensions *application/json - for future use with the api, and for use by extensions *application/xml - for future use with the api, and for use by extensions In PHP, use the corresponding CONTENT_FORMAT_XXX constant. Note that when using the API to access page content, especially action=edit, action=parse and action=query &prop=revisions, the model and format of the content should always be handled explicitly. Without that information, interpretation of the provided content is not reliable. The same applies to XML dumps generated via maintenance/dumpBackup.php or Special:Export. Also note that the API will provide encapsulated, serialized content - so if the API was called with format=json, and contentformat is also json(or rather, application/json), the page content is represented as a string containing an escaped json structure. Extensions that use JSON to serialize some types of page content may provide specialized API modules that allow access to that content in a more natural form.==Compatibility==The ContentHandler facility is introduced in a way that should allow all existing code to keep functioning at least for pages that contain wikitext or other text based content. However, a number of functions and hooks have been deprecated in favor of new versions that are aware of the page 's content model, and will now generate warnings when used. Most importantly, the following functions have been deprecated:*Revisions::getText() is deprecated in favor Revisions::getContent() *WikiPage::getText() is deprecated in favor WikiPage::getContent() Also, the old Article::getContent()(which returns text) is superceded by Article::getContentObject(). However, both methods should be avoided since they do not provide clean access to the page 's actual content. For instance, they may return a system message for non-existing pages. Use WikiPage::getContent() instead. Code that relies on a textual representation of the page content should eventually be rewritten. However, ContentHandler::getContentText() provides a stop-gap that can be used to get text for a page. Its behavior is controlled by $wgContentHandlerTextFallback it
Definition: contenthandler.txt:104
Check if we are running from the commandline.
Definition: GlobalFunctions.php:2042
and(b) You must cause any modified files to carry prominent notices stating that You changed the files
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException' returning false will NOT prevent logging a wrapping ErrorException $suppressed
Definition: hooks.txt:2188
static output( $e, $mode, $eNew=null)
Definition: MWExceptionRenderer.php:39
static report( $e)
Report an exception to the user.
Definition: MWExceptionHandler.php:66
We ve cleaned up the code here by removing clumps of infrequently used code and moving them off somewhere else It s much easier for someone working with this code to see what s _really_ going on
Definition: hooks.txt:86
Definition: APACHE-LICENSE-2.0.txt:114
static getRequestId()
Get the unique request ID.
Definition: WebRequest.php:271
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
Definition: distributors.txt:22
MediaWiki Logger LoggerFactory implements a PSR[0] compatible message logging system Named Psr Log LoggerInterface instances can be obtained from the MediaWiki Logger LoggerFactory::getInstance() static method. MediaWiki\Logger\LoggerFactory expects a class implementing the MediaWiki\Logger\Spi interface to act as a factory for new Psr\Log\LoggerInterface instances. The "Spi" in MediaWiki\Logger\Spi stands for "service provider interface". An SPI is an API intended to be implemented or extended by a third party. This software design pattern is intended to enable framework extension and replaceable components. It is specifically used in the MediaWiki\Logger\LoggerFactory service to allow alternate PSR-3 logging implementations to be easily integrated with MediaWiki. The service provider interface allows the backend logging library to be implemented in multiple ways. The $wgMWLoggerDefaultSpi global provides the classname of the default MediaWiki\Logger\Spi implementation to be loaded at runtime. This can either be the name of a class implementing the MediaWiki\Logger\Spi with a zero argument const ructor or a callable that will return an MediaWiki\Logger\Spi instance. Alternately the MediaWiki\Logger\LoggerFactory MediaWiki Logger LoggerFactory
Definition: logger.txt:5
static getGlobalRequestURL()
Return the path and query string portion of the main request URI.
Definition: WebRequest.php:817
null for the wiki Added in
Definition: hooks.txt:1591
you have access to all of the normal MediaWiki so you can get a DB use the etc For full docs on the Maintenance class
Definition: maintenance.txt:56
static jsonSerializeException( $e, $pretty=false, $escaping=0, $catcher=self::CAUGHT_BY_OTHER)
Serialize an Exception object to JSON.
Definition: MWExceptionHandler.php:625
if(! $wgDBerrorLogTZ) $wgRequest
Definition: Setup.php:737
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency MediaWikiServices
Definition: injection.txt:25
static run( $event, array $args=[], $deprecatedVersion=null)
Call hook functions defined in Hooks::register and $wgHooks.
Definition: Hooks.php:203
static handleError( $level, $message, $file=null, $line=null)
Handler for set_error_handler() callback notifications.
Definition: MWExceptionHandler.php:170
shown</td >< td > a href
Definition: All_system_messages.txt:2667
static getRedactedTraceAsString( $e)
Generate a string representation of an exception's stack trace.
Definition: MWExceptionHandler.php:343
do that in ParserLimitReportFormat instead use this to modify the parameters of the image all existing parser cache entries will be invalid To avoid you ll need to handle that somehow(e.g. with the RejectParserCacheValue hook) because MediaWiki won 't do it for you. & $defaults also a ContextSource after deleting those rows but within the same transaction you ll probably need to make sure the header is varied on and they can depend only on the ResourceLoaderContext $context
Definition: hooks.txt:2811
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException' returning false will NOT prevent logging $e
Definition: hooks.txt:2171
static logException( $e, $catcher=self::CAUGHT_BY_OTHER)
Log an exception to the exception log (if enabled).
Definition: MWExceptionHandler.php:645
const AS_RAW
Definition: MWExceptionRenderer.php:31
Definition: testCompression.php:48