includes/SiteConfiguration.php

   1 <?php
   2 /**
   3  * Configuration holder, particularly for multi-wiki sites.
   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  */
  22
  23 use MediaWiki\Shell\Shell;
  24
  25 /**
  26  * This is a class for holding configuration settings, particularly for
  27  * multi-wiki sites.
  28  *
  29  * A basic synopsis:
  30  *
  31  * Consider a wikifarm having three sites: two production sites, one in English
  32  * and one in German, and one testing site. You can assign them easy-to-remember
  33  * identifiers - ISO 639 codes 'en' and 'de' for language wikis, and 'beta' for
  34  * the testing wiki.
  35  *
  36  * You would thus initialize the site configuration by specifying the wiki
  37  * identifiers:
  38  *
  39  * @code
  40  * $conf = new SiteConfiguration;
  41  * $conf->wikis = [ 'de', 'en', 'beta' ];
  42  * @endcode
  43  *
  44  * When configuring the MediaWiki global settings (the $wg variables),
  45  * the identifiers will be available to specify settings on a per wiki basis.
  46  *
  47  * @code
  48  * $conf->settings = [
  49  *      'wgSomeSetting' => [
  50  *
  51  *              # production:
  52  *              'de'     => false,
  53  *              'en'     => false,
  54  *
  55  *              # test:
  56  *              'beta    => true,
  57  *      ],
  58  * ];
  59  * @endcode
  60  *
  61  * With three wikis, that is easy to manage. But what about a farm with
  62  * hundreds of wikis? Site configuration provides a special keyword named
  63  * 'default' which is the value used when a wiki is not found. Hence
  64  * the above code could be written:
  65  *
  66  * @code
  67  * $conf->settings = [
  68  *      'wgSomeSetting' => [
  69  *
  70  *              'default' => false,
  71  *
  72  *              # Enable feature on test
  73  *              'beta'    => true,
  74  *      ],
  75  * ];
  76  * @endcode
  77  *
  78  *
  79  * Since settings can contain arrays, site configuration provides a way
  80  * to merge an array with the default. This is very useful to avoid
  81  * repeating settings again and again while still maintaining specific changes
  82  * on a per wiki basis.
  83  *
  84  * @code
  85  * $conf->settings = [
  86  *      'wgMergeSetting' = [
  87  *              # Value that will be shared among all wikis:
  88  *              'default' => [ NS_USER => true ],
  89  *
  90  *              # Leading '+' means merging the array of value with the defaults
  91  *              '+beta' => [ NS_HELP => true ],
  92  *      ],
  93  * ];
  94  *
  95  * # Get configuration for the German site:
  96  * $conf->get( 'wgMergeSetting', 'de' );
  97  * // --> [ NS_USER => true ];
  98  *
  99  * # Get configuration for the testing site:
 100  * $conf->get( 'wgMergeSetting', 'beta' );
 101  * // --> [ NS_USER => true, NS_HELP => true ];
 102  * @endcode
 103  *
 104  * Finally, to load all configuration settings, extract them in global context:
 105  *
 106  * @code
 107  * # Name / identifier of the wiki as set in $conf->wikis
 108  * $wikiID = 'beta';
 109  * $globals = $conf->getAll( $wikiID );
 110  * extract( $globals );
 111  * @endcode
 112  *
 113  * @note For WikiMap to function, the configuration must define string values for
 114  *  $wgServer (or $wgCanonicalServer) and $wgArticlePath, even if these are the
 115  *  same for all wikis or can be correctly determined by the logic in
 116  *  Setup.php.
 117  *
 118  * @todo Give examples for,
 119  * suffixes:
 120  * $conf->suffixes = [ 'wiki' ];
 121  * localVHosts
 122  * callbacks!
 123  */
 124 class SiteConfiguration {
 125
 126         /**
 127          * Array of suffixes, for self::siteFromDB()
 128          */
 129         public $suffixes = [];
 130
 131         /**
 132          * Array of wikis, should be the same as $wgLocalDatabases
 133          */
 134         public $wikis = [];
 135
 136         /**
 137          * The whole array of settings
 138          */
 139         public $settings = [];
 140
 141         /**
 142          * Array of domains that are local and can be handled by the same server
 143          *
 144          * @deprecated since 1.25; use $wgLocalVirtualHosts instead.
 145          */
 146         public $localVHosts = [];
 147
 148         /**
 149          * Optional callback to load full configuration data.
 150          * @var string|array
 151          */
 152         public $fullLoadCallback = null;
 153
 154         /** Whether or not all data has been loaded */
 155         public $fullLoadDone = false;
 156
 157         /**
 158          * A callback function that returns an array with the following keys (all
 159          * optional):
 160          * - suffix: site's suffix
 161          * - lang: site's lang
 162          * - tags: array of wiki tags
 163          * - params: array of parameters to be replaced
 164          * The function will receive the SiteConfiguration instance in the first
 165          * argument and the wiki in the second one.
 166          * if suffix and lang are passed they will be used for the return value of
 167          * self::siteFromDB() and self::$suffixes will be ignored
 168          *
 169          * @var string|array
 170          */
 171         public $siteParamsCallback = null;
 172
 173         /**
 174          * Configuration cache for getConfig()
 175          * @var array
 176          */
 177         protected $cfgCache = [];
 178
 179         /**
 180          * Retrieves a configuration setting for a given wiki.
 181          * @param string $settingName ID of the setting name to retrieve
 182          * @param string $wiki Wiki ID of the wiki in question.
 183          * @param string|null $suffix The suffix of the wiki in question.
 184          * @param array $params List of parameters. $.'key' is replaced by $value in all returned data.
 185          * @param array $wikiTags The tags assigned to the wiki.
 186          * @return mixed The value of the setting requested.
 187          */
 188         public function get( $settingName, $wiki, $suffix = null, $params = [],
 189                 $wikiTags = []
 190         ) {
 191                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 192                 return $this->getSetting( $settingName, $wiki, $params );
 193         }
 194
 195         /**
 196          * Really retrieves a configuration setting for a given wiki.
 197          *
 198          * @param string $settingName ID of the setting name to retrieve.
 199          * @param string $wiki Wiki ID of the wiki in question.
 200          * @param array $params Array of parameters.
 201          * @return mixed The value of the setting requested.
 202          */
 203         protected function getSetting( $settingName, $wiki, array $params ) {
 204                 $retval = null;
 205                 if ( array_key_exists( $settingName, $this->settings ) ) {
 206                         $thisSetting =& $this->settings[$settingName];
 207                         do {
 208                                 // Do individual wiki settings
 209                                 if ( array_key_exists( $wiki, $thisSetting ) ) {
 210                                         $retval = $thisSetting[$wiki];
 211                                         break;
 212                                 } elseif ( array_key_exists( "+$wiki", $thisSetting ) && is_array( $thisSetting["+$wiki"] ) ) {
 213                                         $retval = $thisSetting["+$wiki"];
 214                                 }
 215
 216                                 // Do tag settings
 217                                 foreach ( $params['tags'] as $tag ) {
 218                                         if ( array_key_exists( $tag, $thisSetting ) ) {
 219                                                 if ( is_array( $retval ) && is_array( $thisSetting[$tag] ) ) {
 220                                                         $retval = self::arrayMerge( $retval, $thisSetting[$tag] );
 221                                                 } else {
 222                                                         $retval = $thisSetting[$tag];
 223                                                 }
 224                                                 break 2;
 225                                         } elseif ( array_key_exists( "+$tag", $thisSetting ) && is_array( $thisSetting["+$tag"] ) ) {
 226                                                 if ( $retval === null ) {
 227                                                         $retval = [];
 228                                                 }
 229                                                 $retval = self::arrayMerge( $retval, $thisSetting["+$tag"] );
 230                                         }
 231                                 }
 232                                 // Do suffix settings
 233                                 $suffix = $params['suffix'];
 234                                 if ( !is_null( $suffix ) ) {
 235                                         if ( array_key_exists( $suffix, $thisSetting ) ) {
 236                                                 if ( is_array( $retval ) && is_array( $thisSetting[$suffix] ) ) {
 237                                                         $retval = self::arrayMerge( $retval, $thisSetting[$suffix] );
 238                                                 } else {
 239                                                         $retval = $thisSetting[$suffix];
 240                                                 }
 241                                                 break;
 242                                         } elseif ( array_key_exists( "+$suffix", $thisSetting )
 243                                                 && is_array( $thisSetting["+$suffix"] )
 244                                         ) {
 245                                                 if ( $retval === null ) {
 246                                                         $retval = [];
 247                                                 }
 248                                                 $retval = self::arrayMerge( $retval, $thisSetting["+$suffix"] );
 249                                         }
 250                                 }
 251
 252                                 // Fall back to default.
 253                                 if ( array_key_exists( 'default', $thisSetting ) ) {
 254                                         if ( is_array( $retval ) && is_array( $thisSetting['default'] ) ) {
 255                                                 $retval = self::arrayMerge( $retval, $thisSetting['default'] );
 256                                         } else {
 257                                                 $retval = $thisSetting['default'];
 258                                         }
 259                                         break;
 260                                 }
 261                         } while ( false );
 262                 }
 263
 264                 if ( !is_null( $retval ) && count( $params['params'] ) ) {
 265                         foreach ( $params['params'] as $key => $value ) {
 266                                 $retval = $this->doReplace( '$' . $key, $value, $retval );
 267                         }
 268                 }
 269                 return $retval;
 270         }
 271
 272         /**
 273          * Type-safe string replace; won't do replacements on non-strings
 274          * private?
 275          *
 276          * @param string $from
 277          * @param string $to
 278          * @param string|array $in
 279          * @return string|array
 280          */
 281         function doReplace( $from, $to, $in ) {
 282                 if ( is_string( $in ) ) {
 283                         return str_replace( $from, $to, $in );
 284                 } elseif ( is_array( $in ) ) {
 285                         foreach ( $in as $key => $val ) {
 286                                 $in[$key] = $this->doReplace( $from, $to, $val );
 287                         }
 288                         return $in;
 289                 } else {
 290                         return $in;
 291                 }
 292         }
 293
 294         /**
 295          * Gets all settings for a wiki
 296          * @param string $wiki Wiki ID of the wiki in question.
 297          * @param string|null $suffix The suffix of the wiki in question.
 298          * @param array $params List of parameters. $.'key' is replaced by $value in all returned data.
 299          * @param array $wikiTags The tags assigned to the wiki.
 300          * @return array Array of settings requested.
 301          */
 302         public function getAll( $wiki, $suffix = null, $params = [], $wikiTags = [] ) {
 303                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 304                 $localSettings = [];
 305                 foreach ( $this->settings as $varname => $stuff ) {
 306                         $append = false;
 307                         $var = $varname;
 308                         if ( substr( $varname, 0, 1 ) == '+' ) {
 309                                 $append = true;
 310                                 $var = substr( $varname, 1 );
 311                         }
 312
 313                         $value = $this->getSetting( $varname, $wiki, $params );
 314                         if ( $append && is_array( $value ) && is_array( $GLOBALS[$var] ) ) {
 315                                 $value = self::arrayMerge( $value, $GLOBALS[$var] );
 316                         }
 317                         if ( !is_null( $value ) ) {
 318                                 $localSettings[$var] = $value;
 319                         }
 320                 }
 321                 return $localSettings;
 322         }
 323
 324         /**
 325          * Retrieves a configuration setting for a given wiki, forced to a boolean.
 326          * @param string $setting ID of the setting name to retrieve
 327          * @param string $wiki Wiki ID of the wiki in question.
 328          * @param string|null $suffix The suffix of the wiki in question.
 329          * @param array $wikiTags The tags assigned to the wiki.
 330          * @return bool The value of the setting requested.
 331          */
 332         public function getBool( $setting, $wiki, $suffix = null, $wikiTags = [] ) {
 333                 return (bool)$this->get( $setting, $wiki, $suffix, [], $wikiTags );
 334         }
 335
 336         /**
 337          * Retrieves an array of local databases
 338          *
 339          * @return array
 340          */
 341         function &getLocalDatabases() {
 342                 return $this->wikis;
 343         }
 344
 345         /**
 346          * Retrieves the value of a given setting, and places it in a variable passed by reference.
 347          * @param string $setting ID of the setting name to retrieve
 348          * @param string $wiki Wiki ID of the wiki in question.
 349          * @param string $suffix The suffix of the wiki in question.
 350          * @param array &$var Reference The variable to insert the value into.
 351          * @param array $params List of parameters. $.'key' is replaced by $value in all returned data.
 352          * @param array $wikiTags The tags assigned to the wiki.
 353          */
 354         public function extractVar( $setting, $wiki, $suffix, &$var,
 355                 $params = [], $wikiTags = []
 356         ) {
 357                 $value = $this->get( $setting, $wiki, $suffix, $params, $wikiTags );
 358                 if ( !is_null( $value ) ) {
 359                         $var = $value;
 360                 }
 361         }
 362
 363         /**
 364          * Retrieves the value of a given setting, and places it in its corresponding global variable.
 365          * @param string $setting ID of the setting name to retrieve
 366          * @param string $wiki Wiki ID of the wiki in question.
 367          * @param string|null $suffix The suffix of the wiki in question.
 368          * @param array $params List of parameters. $.'key' is replaced by $value in all returned data.
 369          * @param array $wikiTags The tags assigned to the wiki.
 370          */
 371         public function extractGlobal( $setting, $wiki, $suffix = null,
 372                 $params = [], $wikiTags = []
 373         ) {
 374                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 375                 $this->extractGlobalSetting( $setting, $wiki, $params );
 376         }
 377
 378         /**
 379          * @param string $setting
 380          * @param string $wiki
 381          * @param array $params
 382          */
 383         public function extractGlobalSetting( $setting, $wiki, $params ) {
 384                 $value = $this->getSetting( $setting, $wiki, $params );
 385                 if ( !is_null( $value ) ) {
 386                         if ( substr( $setting, 0, 1 ) == '+' && is_array( $value ) ) {
 387                                 $setting = substr( $setting, 1 );
 388                                 if ( is_array( $GLOBALS[$setting] ) ) {
 389                                         $GLOBALS[$setting] = self::arrayMerge( $GLOBALS[$setting], $value );
 390                                 } else {
 391                                         $GLOBALS[$setting] = $value;
 392                                 }
 393                         } else {
 394                                 $GLOBALS[$setting] = $value;
 395                         }
 396                 }
 397         }
 398
 399         /**
 400          * Retrieves the values of all settings, and places them in their corresponding global variables.
 401          * @param string $wiki Wiki ID of the wiki in question.
 402          * @param string|null $suffix The suffix of the wiki in question.
 403          * @param array $params List of parameters. $.'key' is replaced by $value in all returned data.
 404          * @param array $wikiTags The tags assigned to the wiki.
 405          */
 406         public function extractAllGlobals( $wiki, $suffix = null, $params = [],
 407                 $wikiTags = []
 408         ) {
 409                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 410                 foreach ( $this->settings as $varName => $setting ) {
 411                         $this->extractGlobalSetting( $varName, $wiki, $params );
 412                 }
 413         }
 414
 415         /**
 416          * Return specific settings for $wiki
 417          * See the documentation of self::$siteParamsCallback for more in-depth
 418          * documentation about this function
 419          *
 420          * @param string $wiki
 421          * @return array
 422          */
 423         protected function getWikiParams( $wiki ) {
 424                 static $default = [
 425                         'suffix' => null,
 426                         'lang' => null,
 427                         'tags' => [],
 428                         'params' => [],
 429                 ];
 430
 431                 if ( !is_callable( $this->siteParamsCallback ) ) {
 432                         return $default;
 433                 }
 434
 435                 $ret = ( $this->siteParamsCallback )( $this, $wiki );
 436                 # Validate the returned value
 437                 if ( !is_array( $ret ) ) {
 438                         return $default;
 439                 }
 440
 441                 foreach ( $default as $name => $def ) {
 442                         if ( !isset( $ret[$name] ) || ( is_array( $default[$name] ) && !is_array( $ret[$name] ) ) ) {
 443                                 $ret[$name] = $default[$name];
 444                         }
 445                 }
 446
 447                 return $ret;
 448         }
 449
 450         /**
 451          * Merge params between the ones passed to the function and the ones given
 452          * by self::$siteParamsCallback for backward compatibility
 453          * Values returned by self::getWikiParams() have the priority.
 454          *
 455          * @param string $wiki Wiki ID of the wiki in question.
 456          * @param string $suffix The suffix of the wiki in question.
 457          * @param array $params List of parameters. $.'key' is replaced by $value in
 458          *   all returned data.
 459          * @param array $wikiTags The tags assigned to the wiki.
 460          * @return array
 461          */
 462         protected function mergeParams( $wiki, $suffix, array $params, array $wikiTags ) {
 463                 $ret = $this->getWikiParams( $wiki );
 464
 465                 if ( is_null( $ret['suffix'] ) ) {
 466                         $ret['suffix'] = $suffix;
 467                 }
 468
 469                 $ret['tags'] = array_unique( array_merge( $ret['tags'], $wikiTags ) );
 470
 471                 $ret['params'] += $params;
 472
 473                 // Automatically fill that ones if needed
 474                 if ( !isset( $ret['params']['lang'] ) && !is_null( $ret['lang'] ) ) {
 475                         $ret['params']['lang'] = $ret['lang'];
 476                 }
 477                 if ( !isset( $ret['params']['site'] ) && !is_null( $ret['suffix'] ) ) {
 478                         $ret['params']['site'] = $ret['suffix'];
 479                 }
 480
 481                 return $ret;
 482         }
 483
 484         /**
 485          * Work out the site and language name from a database name
 486          * @param string $wiki Wiki ID
 487          *
 488          * @return array
 489          */
 490         public function siteFromDB( $wiki ) {
 491                 // Allow override
 492                 $def = $this->getWikiParams( $wiki );
 493                 if ( !is_null( $def['suffix'] ) && !is_null( $def['lang'] ) ) {
 494                         return [ $def['suffix'], $def['lang'] ];
 495                 }
 496
 497                 $site = null;
 498                 $lang = null;
 499                 foreach ( $this->suffixes as $altSite => $suffix ) {
 500                         if ( $suffix === '' ) {
 501                                 $site = '';
 502                                 $lang = $wiki;
 503                                 break;
 504                         } elseif ( substr( $wiki, -strlen( $suffix ) ) == $suffix ) {
 505                                 $site = is_numeric( $altSite ) ? $suffix : $altSite;
 506                                 $lang = substr( $wiki, 0, strlen( $wiki ) - strlen( $suffix ) );
 507                                 break;
 508                         }
 509                 }
 510                 $lang = str_replace( '_', '-', $lang );
 511
 512                 return [ $site, $lang ];
 513         }
 514
 515         /**
 516          * Get the resolved (post-setup) configuration of a potentially foreign wiki.
 517          * For foreign wikis, this is expensive, and only works if maintenance
 518          * scripts are setup to handle the --wiki parameter such as in wiki farms.
 519          *
 520          * @param string $wiki
 521          * @param array|string $settings A setting name or array of setting names
 522          * @return mixed|mixed[] Array if $settings is an array, otherwise the value
 523          * @throws MWException
 524          * @since 1.21
 525          */
 526         public function getConfig( $wiki, $settings ) {
 527                 global $IP;
 528
 529                 $multi = is_array( $settings );
 530                 $settings = (array)$settings;
 531                 if ( WikiMap::isCurrentWikiId( $wiki ) ) { // $wiki is this wiki
 532                         $res = [];
 533                         foreach ( $settings as $name ) {
 534                                 if ( !preg_match( '/^wg[A-Z]/', $name ) ) {
 535                                         throw new MWException( "Variable '$name' does start with 'wg'." );
 536                                 } elseif ( !isset( $GLOBALS[$name] ) ) {
 537                                         throw new MWException( "Variable '$name' is not set." );
 538                                 }
 539                                 $res[$name] = $GLOBALS[$name];
 540                         }
 541                 } else { // $wiki is a foreign wiki
 542                         if ( isset( $this->cfgCache[$wiki] ) ) {
 543                                 $res = array_intersect_key( $this->cfgCache[$wiki], array_flip( $settings ) );
 544                                 if ( count( $res ) == count( $settings ) ) {
 545                                         return $multi ? $res : current( $res ); // cache hit
 546                                 }
 547                         } elseif ( !in_array( $wiki, $this->wikis ) ) {
 548                                 throw new MWException( "No such wiki '$wiki'." );
 549                         } else {
 550                                 $this->cfgCache[$wiki] = [];
 551                         }
 552                         $result = Shell::makeScriptCommand(
 553                                 "$IP/maintenance/getConfiguration.php",
 554                                 [
 555                                         '--wiki', $wiki,
 556                                         '--settings', implode( ' ', $settings ),
 557                                         '--format', 'PHP',
 558                                 ]
 559                         )
 560                                 // limit.sh breaks this call
 561                                 ->limits( [ 'memory' => 0, 'filesize' => 0 ] )
 562                                 ->execute();
 563
 564                         $data = trim( $result->getStdout() );
 565                         if ( $result->getExitCode() || $data === '' ) {
 566                                 throw new MWException( "Failed to run getConfiguration.php: {$result->getStdout()}" );
 567                         }
 568                         $res = unserialize( $data );
 569                         if ( !is_array( $res ) ) {
 570                                 throw new MWException( "Failed to unserialize configuration array." );
 571                         }
 572                         $this->cfgCache[$wiki] = $this->cfgCache[$wiki] + $res;
 573                 }
 574
 575                 return $multi ? $res : current( $res );
 576         }
 577
 578         /**
 579          * Merge multiple arrays together.
 580          * On encountering duplicate keys, merge the two, but ONLY if they're arrays.
 581          * PHP's array_merge_recursive() merges ANY duplicate values into arrays,
 582          * which is not fun
 583          *
 584          * @param array $array1
 585          * @param array ...$arrays
 586          *
 587          * @return array
 588          */
 589         static function arrayMerge( array $array1, ...$arrays ) {
 590                 $out = $array1;
 591                 foreach ( $arrays as $array ) {
 592                         foreach ( $array as $key => $value ) {
 593                                 if ( isset( $out[$key] ) && is_array( $out[$key] ) && is_array( $value ) ) {
 594                                         $out[$key] = self::arrayMerge( $out[$key], $value );
 595                                 } elseif ( !isset( $out[$key] ) || !$out[$key] && !is_numeric( $key ) ) {
 596                                         // Values that evaluate to true given precedence, for the
 597                                         // primary purpose of merging permissions arrays.
 598                                         $out[$key] = $value;
 599                                 } elseif ( is_numeric( $key ) ) {
 600                                         $out[] = $value;
 601                                 }
 602                         }
 603                 }
 604
 605                 return $out;
 606         }
 607
 608         public function loadFullData() {
 609                 if ( $this->fullLoadCallback && !$this->fullLoadDone ) {
 610                         ( $this->fullLoadCallback )( $this );
 611                         $this->fullLoadDone = true;
 612                 }
 613         }
 614 }