Current File : //www/varak.net/wiki.varak.net/includes/db/DatabaseError.php
<?php
/**
* This file contains database error classes.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Database
*/
/**
* Database error base class
* @ingroup Database
*/
class DBError extends MWException {
/** @var DatabaseBase */
public $db;
/**
* Construct a database error
* @param DatabaseBase $db Object which threw the error
* @param string $error A simple error message to be used for debugging
*/
function __construct( DatabaseBase $db = null, $error ) {
$this->db = $db;
parent::__construct( $error );
}
}
/**
* Base class for the more common types of database errors. These are known to occur
* frequently, so we try to give friendly error messages for them.
*
* @ingroup Database
* @since 1.23
*/
class DBExpectedError extends DBError {
/**
* @return string
*/
function getText() {
global $wgShowDBErrorBacktrace;
$s = $this->getTextContent() . "\n";
if ( $wgShowDBErrorBacktrace ) {
$s .= "Backtrace:\n" . $this->getTraceAsString() . "\n";
}
return $s;
}
/**
* @return string
*/
function getHTML() {
global $wgShowDBErrorBacktrace;
$s = $this->getHTMLContent();
if ( $wgShowDBErrorBacktrace ) {
$s .= '<p>Backtrace:</p><pre>' . htmlspecialchars( $this->getTraceAsString() ) . '</pre>';
}
return $s;
}
function getPageTitle() {
return $this->msg( 'databaseerror', 'Database error' );
}
/**
* @return string
*/
protected function getTextContent() {
return $this->getMessage();
}
/**
* @return string
*/
protected function getHTMLContent() {
return '<p>' . nl2br( htmlspecialchars( $this->getTextContent() ) ) . '</p>';
}
}
/**
* @ingroup Database
*/
class DBConnectionError extends DBExpectedError {
/** @var string Error text */
public $error;
/**
* @param DatabaseBase $db Object throwing the error
* @param string $error Error text
*/
function __construct( DatabaseBase $db = null, $error = 'unknown error' ) {
$msg = 'DB connection error';
if ( trim( $error ) != '' ) {
$msg .= ": $error";
} elseif ( $db ) {
$error = $this->db->getServer();
}
parent::__construct( $db, $msg );
$this->error = $error;
}
/**
* @return bool
*/
function useOutputPage() {
// Not likely to work
return false;
}
/**
* @param string $key
* @param string $fallback Unescaped alternative error text in case the
* message cache cannot be used. Can contain parameters as in regular
* messages, that should be passed as additional parameters.
* @return string Unprocessed plain error text with parameters replaced
*/
function msg( $key, $fallback /*[, params...] */ ) {
$args = array_slice( func_get_args(), 2 );
if ( $this->useMessageCache() ) {
return wfMessage( $key, $args )->useDatabase( false )->text();
} else {
return wfMsgReplaceArgs( $fallback, $args );
}
}
/**
* @return bool
*/
function isLoggable() {
// Don't send to the exception log, already in dberror log
return false;
}
/**
* @return string Safe HTML
*/
function getHTML() {
global $wgShowDBErrorBacktrace, $wgShowHostnames, $wgShowSQLErrors;
$sorry = htmlspecialchars( $this->msg(
'dberr-problems',
'Sorry! This site is experiencing technical difficulties.'
) );
$again = htmlspecialchars( $this->msg(
'dberr-again',
'Try waiting a few minutes and reloading.'
) );
if ( $wgShowHostnames || $wgShowSQLErrors ) {
$info = str_replace(
'$1', Html::element( 'span', [ 'dir' => 'ltr' ], $this->error ),
htmlspecialchars( $this->msg( 'dberr-info', '(Cannot access the database: $1)' ) )
);
} else {
$info = htmlspecialchars( $this->msg(
'dberr-info-hidden',
'(Cannot access the database)'
) );
}
# No database access
MessageCache::singleton()->disable();
$html = "<h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
if ( $wgShowDBErrorBacktrace ) {
$html .= '<p>Backtrace:</p><pre>' . htmlspecialchars( $this->getTraceAsString() ) . '</pre>';
}
$html .= '<hr />';
$html .= $this->searchForm();
return $html;
}
protected function getTextContent() {
global $wgShowHostnames, $wgShowSQLErrors;
if ( $wgShowHostnames || $wgShowSQLErrors ) {
return $this->getMessage();
} else {
return 'DB connection error';
}
}
/**
* Output the exception report using HTML.
*
* @return void
*/
public function reportHTML() {
global $wgUseFileCache;
// Check whether we can serve a file-cached copy of the page with the error underneath
if ( $wgUseFileCache ) {
try {
$cache = $this->fileCachedPage();
// Cached version on file system?
if ( $cache !== null ) {
// Hack: extend the body for error messages
$cache = str_replace( [ '</html>', '</body>' ], '', $cache );
// Add cache notice...
$cache .= '<div style="border:1px solid #ffd0d0;padding:1em;">' .
htmlspecialchars( $this->msg( 'dberr-cachederror',
'This is a cached copy of the requested page, and may not be up to date.' ) ) .
'</div>';
// Output cached page with notices on bottom and re-close body
echo "{$cache}<hr />{$this->getHTML()}</body></html>";
return;
}
} catch ( Exception $e ) {
// Do nothing, just use the default page
}
}
// We can't, cough and die in the usual fashion
parent::reportHTML();
}
/**
* @return string
*/
function searchForm() {
global $wgSitename, $wgCanonicalServer, $wgRequest;
$usegoogle = htmlspecialchars( $this->msg(
'dberr-usegoogle',
'You can try searching via Google in the meantime.'
) );
$outofdate = htmlspecialchars( $this->msg(
'dberr-outofdate',
'Note that their indexes of our content may be out of date.'
) );
$googlesearch = htmlspecialchars( $this->msg( 'searchbutton', 'Search' ) );
$search = htmlspecialchars( $wgRequest->getVal( 'search' ) );
$server = htmlspecialchars( $wgCanonicalServer );
$sitename = htmlspecialchars( $wgSitename );
$trygoogle = <<<EOT
<div style="margin: 1.5em">$usegoogle<br />
<small>$outofdate</small>
</div>
<form method="get" action="//www.google.com/search" id="googlesearch">
<input type="hidden" name="domains" value="$server" />
<input type="hidden" name="num" value="50" />
<input type="hidden" name="ie" value="UTF-8" />
<input type="hidden" name="oe" value="UTF-8" />
<input type="text" name="q" size="31" maxlength="255" value="$search" />
<input type="submit" name="btnG" value="$googlesearch" />
<p>
<label><input type="radio" name="sitesearch" value="$server" checked="checked" />$sitename</label>
<label><input type="radio" name="sitesearch" value="" />WWW</label>
</p>
</form>
EOT;
return $trygoogle;
}
/**
* @return string
*/
private function fileCachedPage() {
$context = RequestContext::getMain();
if ( $context->getOutput()->isDisabled() ) {
// Done already?
return '';
}
if ( $context->getTitle() ) {
// Use the main context's title if we managed to set it
$t = $context->getTitle()->getPrefixedDBkey();
} else {
// Fallback to the raw title URL param. We can't use the Title
// class is it may hit the interwiki table and give a DB error.
// We may get a cache miss due to not sanitizing the title though.
$t = str_replace( ' ', '_', $context->getRequest()->getVal( 'title' ) );
if ( $t == '' ) { // fallback to main page
$t = Title::newFromText(
$this->msg( 'mainpage', 'Main Page' ) )->getPrefixedDBkey();
}
}
$cache = new HTMLFileCache( $t, 'view' );
if ( $cache->isCached() ) {
return $cache->fetchText();
} else {
return '';
}
}
}
/**
* @ingroup Database
*/
class DBQueryError extends DBExpectedError {
public $error, $errno, $sql, $fname;
/**
* @param DatabaseBase $db
* @param string $error
* @param int|string $errno
* @param string $sql
* @param string $fname
*/
function __construct( DatabaseBase $db, $error, $errno, $sql, $fname ) {
if ( $db->wasConnectionError( $errno ) ) {
$message = "A connection error occured. \n" .
"Query: $sql\n" .
"Function: $fname\n" .
"Error: $errno $error\n";
} else {
$message = "A database error has occurred. Did you forget to run " .
"maintenance/update.php after upgrading? See: " .
"https://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script\n" .
"Query: $sql\n" .
"Function: $fname\n" .
"Error: $errno $error\n";
}
parent::__construct( $db, $message );
$this->error = $error;
$this->errno = $errno;
$this->sql = $sql;
$this->fname = $fname;
}
/**
* @return string
*/
function getPageTitle() {
return $this->msg( 'databaseerror', 'Database error' );
}
/**
* @return string
*/
protected function getHTMLContent() {
$key = 'databaseerror-text';
$s = Html::element( 'p', [], $this->msg( $key, $this->getFallbackMessage( $key ) ) );
$details = $this->getTechnicalDetails();
if ( $details ) {
$s .= '<ul>';
foreach ( $details as $key => $detail ) {
$s .= str_replace(
'$1', call_user_func_array( 'Html::element', $detail ),
Html::element( 'li', [],
$this->msg( $key, $this->getFallbackMessage( $key ) )
)
);
}
$s .= '</ul>';
}
return $s;
}
/**
* @return string
*/
protected function getTextContent() {
$key = 'databaseerror-textcl';
$s = $this->msg( $key, $this->getFallbackMessage( $key ) ) . "\n";
foreach ( $this->getTechnicalDetails() as $key => $detail ) {
$s .= $this->msg( $key, $this->getFallbackMessage( $key ), $detail[2] ) . "\n";
}
return $s;
}
/**
* Make a list of technical details that can be shown to the user. This information can
* aid in debugging yet may be useful to an attacker trying to exploit a security weakness
* in the software or server configuration.
*
* Thus no such details are shown by default, though if $wgShowHostnames is true, only the
* full SQL query is hidden; in fact, the error message often does contain a hostname, and
* sites using this option probably don't care much about "security by obscurity". Of course,
* if $wgShowSQLErrors is true, the SQL query *is* shown.
*
* @return array Keys are message keys; values are arrays of arguments for Html::element().
* Array will be empty if users are not allowed to see any of these details at all.
*/
protected function getTechnicalDetails() {
global $wgShowHostnames, $wgShowSQLErrors;
$attribs = [ 'dir' => 'ltr' ];
$details = [];
if ( $wgShowSQLErrors ) {
$details['databaseerror-query'] = [
'div', [ 'class' => 'mw-code' ] + $attribs, $this->sql ];
}
if ( $wgShowHostnames || $wgShowSQLErrors ) {
$errorMessage = $this->errno . ' ' . $this->error;
$details['databaseerror-function'] = [ 'code', $attribs, $this->fname ];
$details['databaseerror-error'] = [ 'samp', $attribs, $errorMessage ];
}
return $details;
}
/**
* @param string $key Message key
* @return string English message text
*/
private function getFallbackMessage( $key ) {
$messages = [
'databaseerror-text' => 'A database query error has occurred.
This may indicate a bug in the software.',
'databaseerror-textcl' => 'A database query error has occurred.',
'databaseerror-query' => 'Query: $1',
'databaseerror-function' => 'Function: $1',
'databaseerror-error' => 'Error: $1',
];
return $messages[$key];
}
}
/**
* @ingroup Database
*/
class DBUnexpectedError extends DBError {
}
/**
* @ingroup Database
*/
class DBReadOnlyError extends DBExpectedError {
function getPageTitle() {
return $this->msg( 'readonly', 'Database is locked' );
}
}
/**
* @ingroup Database
*/
class DBTransactionError extends DBExpectedError {
}
/**
* Exception class for attempted DB access
* @ingroup Database
*/
class DBAccessError extends DBUnexpectedError {
public function __construct() {
parent::__construct( "Mediawiki tried to access the database via wfGetDB(). " .
"This is not allowed, because database access has been disabled." );
}
}
/**
* Exception class for replica DB wait timeouts
* @ingroup Database
*/
class DBReplicationWaitError extends DBUnexpectedError {
}
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