includes/db/DatabaseError.php

   1 <?php
   2 /**
   3  * This file contains database error classes.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Database
  22  */
  23
  24 /**
  25  * Database error base class
  26  * @ingroup Database
  27  */
  28 class DBError extends MWException {
  29
  30         /**
  31          * @var DatabaseBase
  32          */
  33         public $db;
  34
  35         /**
  36          * Construct a database error
  37          * @param $db DatabaseBase object which threw the error
  38          * @param string $error A simple error message to be used for debugging
  39          */
  40         function __construct( DatabaseBase $db = null, $error ) {
  41                 $this->db = $db;
  42                 parent::__construct( $error );
  43         }
  44
  45         /**
  46          * @return string
  47          */
  48         function getText() {
  49                 global $wgShowDBErrorBacktrace;
  50
  51                 $s = $this->getTextContent() . "\n";
  52
  53                 if ( $wgShowDBErrorBacktrace ) {
  54                         $s .= "Backtrace:\n" . $this->getTraceAsString() . "\n";
  55                 }
  56
  57                 return $s;
  58         }
  59
  60         /**
  61          * @return string
  62          */
  63         function getHTML() {
  64                 global $wgShowDBErrorBacktrace;
  65
  66                 $s = $this->getHTMLContent();
  67
  68                 if ( $wgShowDBErrorBacktrace ) {
  69                         $s .= '<p>Backtrace:</p><p>' .
  70                                 nl2br( htmlspecialchars( $this->getTraceAsString() ) ) . '</p>';
  71                 }
  72
  73                 return $s;
  74         }
  75
  76         /**
  77          * @return string
  78          */
  79         protected function getTextContent() {
  80                 return $this->getMessage();
  81         }
  82
  83         /**
  84          * @return string
  85          */
  86         protected function getHTMLContent() {
  87                 return '<p>' . nl2br( htmlspecialchars( $this->getMessage() ) ) . '</p>';
  88         }
  89 }
  90
  91 /**
  92  * @ingroup Database
  93  */
  94 class DBConnectionError extends DBError {
  95         public $error;
  96
  97         function __construct( DatabaseBase $db = null, $error = 'unknown error' ) {
  98                 $msg = 'DB connection error';
  99
 100                 if ( trim( $error ) != '' ) {
 101                         $msg .= ": $error";
 102                 } elseif ( $db ) {
 103                         $error = $this->db->getServer();
 104                 }
 105
 106                 parent::__construct( $db, $msg );
 107                 $this->error = $error;
 108         }
 109
 110         /**
 111          * @return bool
 112          */
 113         function useOutputPage() {
 114                 // Not likely to work
 115                 return false;
 116         }
 117
 118         /**
 119          * @param $key
 120          * @param $fallback
 121          * @return string
 122          */
 123         function msg( $key, $fallback /*[, params...] */ ) {
 124                 global $wgLang;
 125
 126                 $args = array_slice( func_get_args(), 2 );
 127
 128                 if ( $this->useMessageCache() ) {
 129                         $message = $wgLang->getMessage( $key );
 130                 } else {
 131                         $message = $fallback;
 132                 }
 133                 return wfMsgReplaceArgs( $message, $args );
 134         }
 135
 136         /**
 137          * @return bool
 138          */
 139         function getLogMessage() {
 140                 # Don't send to the exception log
 141                 return false;
 142         }
 143
 144         /**
 145          * @return string
 146          */
 147         function getPageTitle() {
 148                 return $this->msg( 'dberr-header', 'This wiki has a problem' );
 149         }
 150
 151         /**
 152          * @return string
 153          */
 154         function getHTML() {
 155                 global $wgShowDBErrorBacktrace, $wgShowHostnames, $wgShowSQLErrors;
 156
 157                 $sorry = htmlspecialchars( $this->msg( 'dberr-problems', "Sorry!\nThis site is experiencing technical difficulties." ) );
 158                 $again = htmlspecialchars( $this->msg( 'dberr-again', 'Try waiting a few minutes and reloading.' ) );
 159
 160                 if ( $wgShowHostnames || $wgShowSQLErrors ) {
 161                         $info = str_replace(
 162                                 '$1', Html::element( 'span', array( 'dir' => 'ltr' ), $this->error ),
 163                                 htmlspecialchars( $this->msg( 'dberr-info', '(Cannot contact the database server: $1)' ) )
 164                         );
 165                 } else {
 166                         $info = htmlspecialchars( $this->msg( 'dberr-info-hidden', '(Cannot contact the database server)' ) );
 167                 }
 168
 169                 # No database access
 170                 MessageCache::singleton()->disable();
 171
 172                 $text = "<h1>$sorry</h1><p>$again</p><p><small>$info</small></p>";
 173
 174                 if ( $wgShowDBErrorBacktrace ) {
 175                         $text .= '<p>Backtrace:</p><p>' .
 176                                 nl2br( htmlspecialchars( $this->getTraceAsString() ) ) . '</p>';
 177                 }
 178
 179                 $text .= '<hr />';
 180                 $text .= $this->searchForm();
 181
 182                 return $text;
 183         }
 184
 185         protected function getTextContent() {
 186                 global $wgShowHostnames, $wgShowSQLErrors;
 187
 188                 if ( $wgShowHostnames || $wgShowSQLErrors ) {
 189                         return $this->getMessage();
 190                 } else {
 191                         return 'DB connection error';
 192                 }
 193         }
 194
 195         public function reportHTML() {
 196                 global $wgUseFileCache;
 197
 198                 # Check whether we can serve a file-cached copy of the page with the error underneath
 199                 if ( $wgUseFileCache ) {
 200                         try {
 201                                 $cache = $this->fileCachedPage();
 202                                 # Cached version on file system?
 203                                 if ( $cache !== null ) {
 204                                         # Hack: extend the body for error messages
 205                                         $cache = str_replace( array( '</html>', '</body>' ), '', $cache );
 206                                         # Add cache notice...
 207                                         $cache .= '<div style="color:red;font-size:150%;font-weight:bold;">' .
 208                                                 htmlspecialchars( $this->msg( 'dberr-cachederror',
 209                                                         'This is a cached copy of the requested page, and may not be up to date. ' ) ) .
 210                                                 '</div>';
 211
 212                                         # Output cached page with notices on bottom and re-close body
 213                                         echo "{$cache}<hr />{$this->getHTML()}</body></html>";
 214                                         return;
 215                                 }
 216                         } catch ( MWException $e ) {
 217                                 // Do nothing, just use the default page
 218                         }
 219                 }
 220
 221                 # We can't, cough and die in the usual fashion
 222                 parent::reportHTML();
 223         }
 224
 225         /**
 226          * @return string
 227          */
 228         function searchForm() {
 229                 global $wgSitename, $wgCanonicalServer, $wgRequest;
 230
 231                 $usegoogle = htmlspecialchars( $this->msg( 'dberr-usegoogle', 'You can try searching via Google in the meantime.' ) );
 232                 $outofdate = htmlspecialchars( $this->msg( 'dberr-outofdate', 'Note that their indexes of our content may be out of date.' ) );
 233                 $googlesearch = htmlspecialchars( $this->msg( 'searchbutton', 'Search' ) );
 234
 235                 $search = htmlspecialchars( $wgRequest->getVal( 'search' ) );
 236
 237                 $server = htmlspecialchars( $wgCanonicalServer );
 238                 $sitename = htmlspecialchars( $wgSitename );
 239
 240                 $trygoogle = <<<EOT
 241 <div style="margin: 1.5em">$usegoogle<br />
 242 <small>$outofdate</small></div>
 243 <!-- SiteSearch Google -->
 244 <form method="get" action="//www.google.com/search" id="googlesearch">
 245         <input type="hidden" name="domains" value="$server" />
 246         <input type="hidden" name="num" value="50" />
 247         <input type="hidden" name="ie" value="UTF-8" />
 248         <input type="hidden" name="oe" value="UTF-8" />
 249
 250         <input type="text" name="q" size="31" maxlength="255" value="$search" />
 251         <input type="submit" name="btnG" value="$googlesearch" />
 252   <div>
 253         <input type="radio" name="sitesearch" id="gwiki" value="$server" checked="checked" /><label for="gwiki">$sitename</label>
 254         <input type="radio" name="sitesearch" id="gWWW" value="" /><label for="gWWW">WWW</label>
 255   </div>
 256 </form>
 257 <!-- SiteSearch Google -->
 258 EOT;
 259                 return $trygoogle;
 260         }
 261
 262         /**
 263          * @return string
 264          */
 265         private function fileCachedPage() {
 266                 global $wgTitle, $wgOut, $wgRequest;
 267
 268                 if ( $wgOut->isDisabled() ) {
 269                         return ''; // Done already?
 270                 }
 271
 272                 if ( $wgTitle ) { // use $wgTitle if we managed to set it
 273                         $t = $wgTitle->getPrefixedDBkey();
 274                 } else {
 275                         # Fallback to the raw title URL param. We can't use the Title
 276                         # class is it may hit the interwiki table and give a DB error.
 277                         # We may get a cache miss due to not sanitizing the title though.
 278                         $t = str_replace( ' ', '_', $wgRequest->getVal( 'title' ) );
 279                         if ( $t == '' ) { // fallback to main page
 280                                 $t = Title::newFromText(
 281                                         $this->msg( 'mainpage', 'Main Page' ) )->getPrefixedDBkey();
 282                         }
 283                 }
 284
 285                 $cache = HTMLFileCache::newFromTitle( $t, 'view' );
 286                 if ( $cache->isCached() ) {
 287                         return $cache->fetchText();
 288                 } else {
 289                         return '';
 290                 }
 291         }
 292 }
 293
 294 /**
 295  * @ingroup Database
 296  */
 297 class DBQueryError extends DBError {
 298         public $error, $errno, $sql, $fname;
 299
 300         /**
 301          * @param $db DatabaseBase
 302          * @param $error string
 303          * @param $errno int|string
 304          * @param $sql string
 305          * @param $fname string
 306          */
 307         function __construct( DatabaseBase $db, $error, $errno, $sql, $fname ) {
 308                 $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" .
 309                         "Query: $sql\n" .
 310                         "Function: $fname\n" .
 311                         "Error: $errno $error\n";
 312                 parent::__construct( $db, $message );
 313
 314                 $this->error = $error;
 315                 $this->errno = $errno;
 316                 $this->sql = $sql;
 317                 $this->fname = $fname;
 318         }
 319
 320         /**
 321          * @return bool
 322          */
 323         function getLogMessage() {
 324                 # Don't send to the exception log
 325                 return false;
 326         }
 327
 328         /**
 329          * @return String
 330          */
 331         function getPageTitle() {
 332                 return $this->msg( 'databaseerror', 'Database error' );
 333         }
 334
 335         /**
 336          * @return string
 337          */
 338         protected function getHTMLContent() {
 339                 $key = 'databaseerror-text';
 340                 $s = Html::element( 'p', array(), $this->msg( $key, $this->getFallbackMessage( $key ) ) );
 341
 342                 $details = $this->getTechnicalDetails();
 343                 if ( $details ) {
 344                         $s .= '<ul>';
 345                         foreach ( $details as $key => $detail ) {
 346                                 $s .= str_replace(
 347                                         '$1', call_user_func_array( 'Html::element', $detail ),
 348                                         Html::element( 'li', array(),
 349                                                 $this->msg( $key, $this->getFallbackMessage( $key ) )
 350                                         )
 351                                 );
 352                         }
 353                         $s .= '</ul>';
 354                 }
 355
 356                 return $s;
 357         }
 358
 359         /**
 360          * @return string
 361          */
 362         protected function getTextContent() {
 363                 $key = 'databaseerror-textcl';
 364                 $s = $this->msg( $key, $this->getFallbackMessage( $key ) ) . "\n";
 365
 366                 foreach ( $this->getTechnicalDetails() as $key => $detail ) {
 367                         $s .= $this->msg( $key, $this->getFallbackMessage( $key ), $detail[2] ) . "\n";
 368                 }
 369
 370                 return $s;
 371         }
 372
 373         /**
 374          * Make a list of technical details that can be shown to the user. This information can
 375          * aid in debugging yet may be useful to an attacker trying to exploit a security weakness
 376          * in the software or server configuration.
 377          *
 378          * Thus no such details are shown by default, though if $wgShowHostnames is true, only the
 379          * full SQL query is hidden; in fact, the error message often does contain a hostname, and
 380          * sites using this option probably don't care much about "security by obscurity". Of course,
 381          * if $wgShowSQLErrors is true, the SQL query *is* shown.
 382          *
 383          * @return array: Keys are message keys; values are arrays of arguments for Html::element().
 384          *   Array will be empty if users are not allowed to see any of these details at all.
 385          */
 386         protected function getTechnicalDetails() {
 387                 global $wgShowHostnames, $wgShowSQLErrors;
 388
 389                 $attribs = array( 'dir' => 'ltr' );
 390                 $details = array();
 391
 392                 if ( $wgShowSQLErrors ) {
 393                         $details['databaseerror-query'] = array(
 394                                 'div', array( 'class' => 'mw-code' ) + $attribs, $this->sql );
 395                 }
 396
 397                 if ( $wgShowHostnames || $wgShowSQLErrors ) {
 398                         $errorMessage = $this->errno . ' ' . $this->error;
 399                         $details['databaseerror-function'] = array( 'code', $attribs, $this->fname );
 400                         $details['databaseerror-error'] = array( 'samp', $attribs, $errorMessage );
 401                 }
 402
 403                 return $details;
 404         }
 405
 406         /**
 407          * @param string $key Message key
 408          * @return string: English message text
 409          */
 410         private function getFallbackMessage( $key ) {
 411                 $messages = array(
 412                         'databaseerror-text' => 'A database query error has occurred.
 413 This may indicate a bug in the software.',
 414                         'databaseerror-textcl' => 'A database query error has occurred.',
 415                         'databaseerror-query' => 'Query: $1',
 416                         'databaseerror-function' => 'Function: $1',
 417                         'databaseerror-error' => 'Error: $1',
 418                 );
 419                 return $messages[$key];
 420         }
 421
 422 }
 423
 424 /**
 425  * @ingroup Database
 426  */
 427 class DBUnexpectedError extends DBError {}