useMessageCache() &&
!empty( $GLOBALS['wgFullyInitialised'] ) &&
!empty( $GLOBALS['wgOut'] ) &&
!empty( $GLOBALS['wgTitle'] );
}
/**
* Whether to log this exception in the exception debug log.
*
* @since 1.23
* @return boolean
*/
function isLoggable() {
return true;
}
/**
* Can the extension use the Message class/wfMessage to get i18n-ed messages?
*
* @return bool
*/
function useMessageCache() {
global $wgLang;
foreach ( $this->getTrace() as $frame ) {
if ( isset( $frame['class'] ) && $frame['class'] === 'LocalisationCache' ) {
return false;
}
}
return $wgLang instanceof Language;
}
/**
* Run hook to allow extensions to modify the text of the exception
*
* @param string $name class name of the exception
* @param array $args arguments to pass to the callback functions
* @return string|null string to output or null if any hook has been called
*/
function runHooks( $name, $args = array() ) {
global $wgExceptionHooks;
if ( !isset( $wgExceptionHooks ) || !is_array( $wgExceptionHooks ) ) {
return null; // Just silently ignore
}
if ( !array_key_exists( $name, $wgExceptionHooks ) || !is_array( $wgExceptionHooks[$name] ) ) {
return null;
}
$hooks = $wgExceptionHooks[$name];
$callargs = array_merge( array( $this ), $args );
foreach ( $hooks as $hook ) {
if ( is_string( $hook ) || ( is_array( $hook ) && count( $hook ) >= 2 && is_string( $hook[0] ) ) ) { // 'function' or array( 'class', hook' )
$result = call_user_func_array( $hook, $callargs );
} else {
$result = null;
}
if ( is_string( $result ) ) {
return $result;
}
}
return null;
}
/**
* Get a message from i18n
*
* @param string $key message name
* @param string $fallback default message if the message cache can't be
* called by the exception
* The function also has other parameters that are arguments for the message
* @return string message with arguments replaced
*/
function msg( $key, $fallback /*[, params...] */ ) {
$args = array_slice( func_get_args(), 2 );
if ( $this->useMessageCache() ) {
return wfMessage( $key, $args )->plain();
} else {
return wfMsgReplaceArgs( $fallback, $args );
}
}
/**
* If $wgShowExceptionDetails is true, return a HTML message with a
* backtrace to the error, otherwise show a message to ask to set it to true
* to show that information.
*
* @return string html to output
*/
function getHTML() {
global $wgShowExceptionDetails;
if ( $wgShowExceptionDetails ) {
return '' . nl2br( htmlspecialchars( MWExceptionHandler::getLogMessage( $this ) ) ) .
'
Backtrace:
' . nl2br( htmlspecialchars( MWExceptionHandler::getRedactedTraceAsString( $this ) ) ) .
"
\n";
} else {
return "" .
'[' . MWExceptionHandler::getLogId( $this ) . '] ' .
gmdate( 'Y-m-d H:i:s' ) .
": Fatal exception of type " . get_class( $this ) . "
\n" .
"";
}
}
/**
* Get the text to display when reporting the error on the command line.
* If $wgShowExceptionDetails is true, return a text message with a
* backtrace to the error.
*
* @return string
*/
function getText() {
global $wgShowExceptionDetails;
if ( $wgShowExceptionDetails ) {
return MWExceptionHandler::getLogMessage( $this ) .
"\nBacktrace:\n" . MWExceptionHandler::getRedactedTraceAsString( $this ) . "\n";
} else {
return "Set \$wgShowExceptionDetails = true; " .
"in LocalSettings.php to show detailed debugging information.\n";
}
}
/**
* Return the title of the page when reporting this error in a HTTP response.
*
* @return string
*/
function getPageTitle() {
return $this->msg( 'internalerror', "Internal error" );
}
/**
* Get a the ID for this error.
*
* @since 1.20
* @deprecated since 1.22 Use MWExceptionHandler::getLogId instead.
* @return string
*/
function getLogId() {
wfDeprecated( __METHOD__, '1.22' );
return MWExceptionHandler::getLogId( $this );
}
/**
* Return the requested URL and point to file and line number from which the
* exception occurred
*
* @since 1.8
* @deprecated since 1.22 Use MWExceptionHandler::getLogMessage instead.
* @return string
*/
function getLogMessage() {
wfDeprecated( __METHOD__, '1.22' );
return MWExceptionHandler::getLogMessage( $this );
}
/**
* Output the exception report using HTML.
*/
function reportHTML() {
global $wgOut;
if ( $this->useOutputPage() ) {
$wgOut->prepareErrorPage( $this->getPageTitle() );
$hookResult = $this->runHooks( get_class( $this ) );
if ( $hookResult ) {
$wgOut->addHTML( $hookResult );
} else {
$wgOut->addHTML( $this->getHTML() );
}
$wgOut->output();
} else {
header( "Content-Type: text/html; charset=utf-8" );
echo "\n" .
'' .
'' . htmlspecialchars( $this->getPageTitle() ) . '' .
"\n";
$hookResult = $this->runHooks( get_class( $this ) . "Raw" );
if ( $hookResult ) {
echo $hookResult;
} else {
echo $this->getHTML();
}
echo "\n";
}
}
/**
* Output a report about the exception and takes care of formatting.
* It will be either HTML or plain text based on isCommandLine().
*/
function report() {
global $wgMimeType;
MWExceptionHandler::logException( $this );
if ( defined( 'MW_API' ) ) {
// Unhandled API exception, we can't be sure that format printer is alive
header( 'MediaWiki-API-Error: internal_api_error_' . get_class( $this ) );
wfHttpError( 500, 'Internal Server Error', $this->getText() );
} elseif ( self::isCommandLine() ) {
MWExceptionHandler::printError( $this->getText() );
} else {
header( "HTTP/1.1 500 MediaWiki exception" );
header( "Status: 500 MediaWiki exception", true );
header( "Content-Type: $wgMimeType; charset=utf-8", true );
$this->reportHTML();
}
}
/**
* Check whether we are in command line mode or not to report the exception
* in the correct format.
*
* @return bool
*/
static function isCommandLine() {
return !empty( $GLOBALS['wgCommandLineMode'] );
}
}
/**
* Exception class which takes an HTML error message, and does not
* produce a backtrace. Replacement for OutputPage::fatalError().
*
* @since 1.7
* @ingroup Exception
*/
class FatalError extends MWException {
/**
* @return string
*/
function getHTML() {
return $this->getMessage();
}
/**
* @return string
*/
function getText() {
return $this->getMessage();
}
}
/**
* An error page which can definitely be safely rendered using the OutputPage.
*
* @since 1.7
* @ingroup Exception
*/
class ErrorPageError extends MWException {
public $title, $msg, $params;
/**
* Note: these arguments are keys into wfMessage(), not text!
*
* @param string|Message $title Message key (string) for page title, or a Message object
* @param string|Message $msg Message key (string) for error text, or a Message object
* @param array $params with parameters to wfMessage()
*/
function __construct( $title, $msg, $params = null ) {
$this->title = $title;
$this->msg = $msg;
$this->params = $params;
// Bug 44111: Messages in the log files should be in English and not
// customized by the local wiki. So get the default English version for
// passing to the parent constructor. Our overridden report() below
// makes sure that the page shown to the user is not forced to English.
if ( $msg instanceof Message ) {
$enMsg = clone( $msg );
} else {
$enMsg = wfMessage( $msg, $params );
}
$enMsg->inLanguage( 'en' )->useDatabase( false );
parent::__construct( $enMsg->text() );
}
function report() {
global $wgOut;
$wgOut->showErrorPage( $this->title, $this->msg, $this->params );
$wgOut->output();
}
}
/**
* Show an error page on a badtitle.
* Similar to ErrorPage, but emit a 400 HTTP error code to let mobile
* browser it is not really a valid content.
*
* @since 1.19
* @ingroup Exception
*/
class BadTitleError extends ErrorPageError {
/**
* @param string|Message $msg A message key (default: 'badtitletext')
* @param array $params parameter to wfMessage()
*/
function __construct( $msg = 'badtitletext', $params = null ) {
parent::__construct( 'badtitle', $msg, $params );
}
/**
* Just like ErrorPageError::report() but additionally set
* a 400 HTTP status code (bug 33646).
*/
function report() {
global $wgOut;
// bug 33646: a badtitle error page need to return an error code
// to let mobile browser now that it is not a normal page.
$wgOut->setStatusCode( 400 );
parent::report();
}
}
/**
* Show an error when a user tries to do something they do not have the necessary
* permissions for.
*
* @since 1.18
* @ingroup Exception
*/
class PermissionsError extends ErrorPageError {
public $permission, $errors;
function __construct( $permission, $errors = array() ) {
global $wgLang;
$this->permission = $permission;
if ( !count( $errors ) ) {
$groups = array_map(
array( 'User', 'makeGroupLinkWiki' ),
User::getGroupsWithPermission( $this->permission )
);
if ( $groups ) {
$errors[] = array( 'badaccess-groups', $wgLang->commaList( $groups ), count( $groups ) );
} else {
$errors[] = array( 'badaccess-group0' );
}
}
$this->errors = $errors;
}
function report() {
global $wgOut;
$wgOut->showPermissionsErrorPage( $this->errors, $this->permission );
$wgOut->output();
}
}
/**
* Show an error when the wiki is locked/read-only and the user tries to do
* something that requires write access.
*
* @since 1.18
* @ingroup Exception
*/
class ReadOnlyError extends ErrorPageError {
public function __construct() {
parent::__construct(
'readonly',
'readonlytext',
wfReadOnlyReason()
);
}
}
/**
* Show an error when the user hits a rate limit.
*
* @since 1.18
* @ingroup Exception
*/
class ThrottledError extends ErrorPageError {
public function __construct() {
parent::__construct(
'actionthrottled',
'actionthrottledtext'
);
}
public function report() {
global $wgOut;
$wgOut->setStatusCode( 503 );
parent::report();
}
}
/**
* Show an error when the user tries to do something whilst blocked.
*
* @since 1.18
* @ingroup Exception
*/
class UserBlockedError extends ErrorPageError {
public function __construct( Block $block ) {
// @todo FIXME: Implement a more proper way to get context here.
$params = $block->getPermissionsError( RequestContext::getMain() );
parent::__construct( 'blockedtitle', array_shift( $params ), $params );
}
}
/**
* Shows a generic "user is not logged in" error page.
*
* This is essentially an ErrorPageError exception which by default uses the
* 'exception-nologin' as a title and 'exception-nologin-text' for the message.
* @see bug 37627
* @since 1.20
*
* @par Example:
* @code
* if( $user->isAnon() ) {
* throw new UserNotLoggedIn();
* }
* @endcode
*
* Note the parameter order differs from ErrorPageError, this allows you to
* simply specify a reason without overriding the default title.
*
* @par Example:
* @code
* if( $user->isAnon() ) {
* throw new UserNotLoggedIn( 'action-require-loggedin' );
* }
* @endcode
*
* @ingroup Exception
*/
class UserNotLoggedIn extends ErrorPageError {
/**
* @param $reasonMsg A message key containing the reason for the error.
* Optional, default: 'exception-nologin-text'
* @param $titleMsg A message key to set the page title.
* Optional, default: 'exception-nologin'
* @param $params Parameters to wfMessage().
* Optional, default: null
*/
public function __construct(
$reasonMsg = 'exception-nologin-text',
$titleMsg = 'exception-nologin',
$params = null
) {
parent::__construct( $titleMsg, $reasonMsg, $params );
}
}
/**
* Show an error that looks like an HTTP server error.
* Replacement for wfHttpError().
*
* @since 1.19
* @ingroup Exception
*/
class HttpError extends MWException {
private $httpCode, $header, $content;
/**
* Constructor
*
* @param $httpCode Integer: HTTP status code to send to the client
* @param string|Message $content content of the message
* @param string|Message $header content of the header (\ and \)
*/
public function __construct( $httpCode, $content, $header = null ) {
parent::__construct( $content );
$this->httpCode = (int)$httpCode;
$this->header = $header;
$this->content = $content;
}
/**
* Returns the HTTP status code supplied to the constructor.
*
* @return int
*/
public function getStatusCode() {
return $this->httpCode;
}
/**
* Report the HTTP error.
* Sends the appropriate HTTP status code and outputs an
* HTML page with an error message.
*/
public function report() {
$httpMessage = HttpStatus::getMessage( $this->httpCode );
header( "Status: {$this->httpCode} {$httpMessage}", true, $this->httpCode );
header( 'Content-type: text/html; charset=utf-8' );
print $this->getHTML();
}
/**
* Returns HTML for reporting the HTTP error.
* This will be a minimal but complete HTML document.
*
* @return string HTML
*/
public function getHTML() {
if ( $this->header === null ) {
$header = HttpStatus::getMessage( $this->httpCode );
} elseif ( $this->header instanceof Message ) {
$header = $this->header->escaped();
} else {
$header = htmlspecialchars( $this->header );
}
if ( $this->content instanceof Message ) {
$content = $this->content->escaped();
} else {
$content = htmlspecialchars( $this->content );
}
return "\n" .
"$header\n" .
"$header
$content
\n";
}
}
/**
* Handler class for MWExceptions
* @ingroup Exception
*/
class MWExceptionHandler {
/**
* Install an exception handler for MediaWiki exception types.
*/
public static function installHandler() {
set_exception_handler( array( 'MWExceptionHandler', 'handle' ) );
}
/**
* Report an exception to the user
*/
protected static function report( Exception $e ) {
global $wgShowExceptionDetails;
$cmdLine = MWException::isCommandLine();
if ( $e instanceof MWException ) {
try {
// Try and show the exception prettily, with the normal skin infrastructure
$e->report();
} catch ( Exception $e2 ) {
// Exception occurred from within exception handler
// Show a simpler error message for the original exception,
// don't try to invoke report()
$message = "MediaWiki internal error.\n\n";
if ( $wgShowExceptionDetails ) {
$message .= 'Original exception: ' . self::getLogMessage( $e ) .
"\nBacktrace:\n" . self::getRedactedTraceAsString( $e ) .
"\n\nException caught inside exception handler: " . self::getLogMessage( $e2 ) .
"\nBacktrace:\n" . self::getRedactedTraceAsString( $e2 );
} else {
$message .= "Exception caught inside exception handler.\n\n" .
"Set \$wgShowExceptionDetails = true; at the bottom of LocalSettings.php " .
"to show detailed debugging information.";
}
$message .= "\n";
if ( $cmdLine ) {
self::printError( $message );
} else {
echo nl2br( htmlspecialchars( $message ) ) . "\n";
}
}
} else {
$message = "Unexpected non-MediaWiki exception encountered, of type \"" . get_class( $e ) . "\"";
if ( $wgShowExceptionDetails ) {
$message .= "\n" . MWExceptionHandler::getLogMessage( $e ) . "\nBacktrace:\n" .
self::getRedactedTraceAsString( $e ) . "\n";
}
if ( $cmdLine ) {
self::printError( $message );
} else {
echo nl2br( htmlspecialchars( $message ) ) . "\n";
}
}
}
/**
* Print a message, if possible to STDERR.
* Use this in command line mode only (see isCommandLine)
*
* @param string $message Failure text
*/
public static function printError( $message ) {
# NOTE: STDERR may not be available, especially if php-cgi is used from the command line (bug #15602).
# Try to produce meaningful output anyway. Using echo may corrupt output to STDOUT though.
if ( defined( 'STDERR' ) ) {
fwrite( STDERR, $message );
} else {
echo $message;
}
}
/**
* Exception handler which simulates the appropriate catch() handling:
*
* try {
* ...
* } catch ( MWException $e ) {
* $e->report();
* } catch ( Exception $e ) {
* echo $e->__toString();
* }
*/
public static function handle( $e ) {
global $wgFullyInitialised;
self::report( $e );
// Final cleanup
if ( $wgFullyInitialised ) {
try {
// uses $wgRequest, hence the $wgFullyInitialised condition
wfLogProfilingData();
} catch ( Exception $e ) {
}
}
// Exit value should be nonzero for the benefit of shell jobs
exit( 1 );
}
/**
* Generate a string representation of an exception's stack trace
*
* Like Exception::getTraceAsString, but replaces argument values with
* argument type or class name.
*
* @param Exception $e
* @return string
*/
public static function getRedactedTraceAsString( Exception $e ) {
$text = '';
foreach ( self::getRedactedTrace( $e ) as $level => $frame ) {
if ( isset( $frame['file'] ) && isset( $frame['line'] ) ) {
$text .= "#{$level} {$frame['file']}({$frame['line']}): ";
} else {
// 'file' and 'line' are unset for calls via call_user_func (bug 55634)
// This matches behaviour of Exception::getTraceAsString to instead
// display "[internal function]".
$text .= "#{$level} [internal function]: ";
}
if ( isset( $frame['class'] ) ) {
$text .= $frame['class'] . $frame['type'] . $frame['function'];
} else {
$text .= $frame['function'];
}
if ( isset( $frame['args'] ) ) {
$text .= '(' . implode( ', ', $frame['args'] ) . ")\n";
} else {
$text .= "()\n";
}
}
$level = $level + 1;
$text .= "#{$level} {main}";
return $text;
}
/**
* Return a copy of an exception's backtrace as an array.
*
* Like Exception::getTrace, but replaces each element in each frame's
* argument array with the name of its class (if the element is an object)
* or its type (if the element is a PHP primitive).
*
* @since 1.22
* @param Exception $e
* @return array
*/
public static function getRedactedTrace( Exception $e ) {
return array_map( function ( $frame ) {
if ( isset( $frame['args'] ) ) {
$frame['args'] = array_map( function ( $arg ) {
return is_object( $arg ) ? get_class( $arg ) : gettype( $arg );
}, $frame['args'] );
}
return $frame;
}, $e->getTrace() );
}
/**
* Get the ID for this error.
*
* The ID is saved so that one can match the one output to the user (when
* $wgShowExceptionDetails is set to false), to the entry in the debug log.
*
* @since 1.22
* @param Exception $e
* @return string
*/
public static function getLogId( Exception $e ) {
if ( !isset( $e->_mwLogId ) ) {
$e->_mwLogId = wfRandomString( 8 );
}
return $e->_mwLogId;
}
/**
* Return the requested URL and point to file and line number from which the
* exception occurred.
*
* @since 1.22
* @param Exception $e
* @return string
*/
public static function getLogMessage( Exception $e ) {
global $wgRequest;
$id = self::getLogId( $e );
$file = $e->getFile();
$line = $e->getLine();
$message = $e->getMessage();
if ( isset( $wgRequest ) && !$wgRequest instanceof FauxRequest ) {
$url = $wgRequest->getRequestURL();
if ( !$url ) {
$url = '[no URL]';
}
} else {
$url = '[no req]';
}
return "[$id] $url Exception from line $line of $file: $message";
}
/**
* Log an exception to the exception log (if enabled).
*
* This method must not assume the exception is an MWException,
* it is also used to handle PHP errors or errors from other libraries.
*
* @since 1.22
* @param Exception $e
*/
public static function logException( Exception $e ) {
global $wgLogExceptionBacktrace;
if ( !( $e instanceof MWException ) || $e->isLoggable() ) {
$log = self::getLogMessage( $e );
if ( $wgLogExceptionBacktrace ) {
wfDebugLog( 'exception', $log . "\n" . $e->getTraceAsString() . "\n" );
} else {
wfDebugLog( 'exception', $log );
}
}
}
}