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