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          */
 142         public $fullLoadCallback = null;
 143
 144         /** Whether or not all data has been loaded */
 145         public $fullLoadDone = false;
 146
 147         /**
 148          * A callback function that returns an array with the following keys (all
 149          * optional):
 150          * - suffix: site's suffix
 151          * - lang: site's lang
 152          * - tags: array of wiki tags
 153          * - params: array of parameters to be replaced
 154          * The function will receive the SiteConfiguration instance in the first
 155          * argument and the wiki in the second one.
 156          * if suffix and lang are passed they will be used for the return value of
 157          * self::siteFromDB() and self::$suffixes will be ignored
 158          */
 159         public $siteParamsCallback = null;
 160
 161         /**
 162          * Retrieves a configuration setting for a given wiki.
 163          * @param $settingName String ID of the setting name to retrieve
 164          * @param $wiki String Wiki ID of the wiki in question.
 165          * @param $suffix String The suffix of the wiki in question.
 166          * @param $params Array List of parameters. $.'key' is replaced by $value in all returned data.
 167          * @param $wikiTags Array The tags assigned to the wiki.
 168          * @return Mixed the value of the setting requested.
 169          */
 170         public function get( $settingName, $wiki, $suffix = null, $params = array(), $wikiTags = array() ) {
 171                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 172                 return $this->getSetting( $settingName, $wiki, $params );
 173         }
 174
 175         /**
 176          * Really retrieves a configuration setting for a given wiki.
 177          *
 178          * @param $settingName String ID of the setting name to retrieve.
 179          * @param $wiki String Wiki ID of the wiki in question.
 180          * @param $params Array: array of parameters.
 181          * @return Mixed the value of the setting requested.
 182          */
 183         protected function getSetting( $settingName, $wiki, /*array*/ $params ){
 184                 $retval = null;
 185                 if( array_key_exists( $settingName, $this->settings ) ) {
 186                         $thisSetting =& $this->settings[$settingName];
 187                         do {
 188                                 // Do individual wiki settings
 189                                 if( array_key_exists( $wiki, $thisSetting ) ) {
 190                                         $retval = $thisSetting[$wiki];
 191                                         break;
 192                                 } elseif( array_key_exists( "+$wiki", $thisSetting ) && is_array( $thisSetting["+$wiki"] ) ) {
 193                                         $retval = $thisSetting["+$wiki"];
 194                                 }
 195
 196                                 // Do tag settings
 197                                 foreach( $params['tags'] as $tag ) {
 198                                         if( array_key_exists( $tag, $thisSetting ) ) {
 199                                                 if ( isset( $retval ) && is_array( $retval ) && is_array( $thisSetting[$tag] ) ) {
 200                                                         $retval = self::arrayMerge( $retval, $thisSetting[$tag] );
 201                                                 } else {
 202                                                         $retval = $thisSetting[$tag];
 203                                                 }
 204                                                 break 2;
 205                                         } elseif( array_key_exists( "+$tag", $thisSetting ) && is_array($thisSetting["+$tag"]) ) {
 206                                                 if( !isset( $retval ) )
 207                                                         $retval = array();
 208                                                 $retval = self::arrayMerge( $retval, $thisSetting["+$tag"] );
 209                                         }
 210                                 }
 211                                 // Do suffix settings
 212                                 $suffix = $params['suffix'];
 213                                 if( !is_null( $suffix ) ) {
 214                                         if( array_key_exists( $suffix, $thisSetting ) ) {
 215                                                 if ( isset($retval) && is_array($retval) && is_array($thisSetting[$suffix]) ) {
 216                                                         $retval = self::arrayMerge( $retval, $thisSetting[$suffix] );
 217                                                 } else {
 218                                                         $retval = $thisSetting[$suffix];
 219                                                 }
 220                                                 break;
 221                                         } elseif( array_key_exists( "+$suffix", $thisSetting ) && is_array($thisSetting["+$suffix"]) ) {
 222                                                 if (!isset($retval))
 223                                                         $retval = array();
 224                                                 $retval = self::arrayMerge( $retval, $thisSetting["+$suffix"] );
 225                                         }
 226                                 }
 227
 228                                 // Fall back to default.
 229                                 if( array_key_exists( 'default', $thisSetting ) ) {
 230                                         if( is_array( $retval ) && is_array( $thisSetting['default'] ) ) {
 231                                                 $retval = self::arrayMerge( $retval, $thisSetting['default'] );
 232                                         } else {
 233                                                 $retval = $thisSetting['default'];
 234                                         }
 235                                         break;
 236                                 }
 237                         } while ( false );
 238                 }
 239
 240                 if( !is_null( $retval ) && count( $params['params'] ) ) {
 241                         foreach ( $params['params'] as $key => $value ) {
 242                                 $retval = $this->doReplace( '$' . $key, $value, $retval );
 243                         }
 244                 }
 245                 return $retval;
 246         }
 247
 248         /**
 249          * Type-safe string replace; won't do replacements on non-strings
 250          * private?
 251          *
 252          * @param $from
 253          * @param $to
 254          * @param $in
 255          * @return string
 256          */
 257         function doReplace( $from, $to, $in ) {
 258                 if( is_string( $in ) ) {
 259                         return str_replace( $from, $to, $in );
 260                 } elseif( is_array( $in ) ) {
 261                         foreach( $in as $key => $val ) {
 262                                 $in[$key] = $this->doReplace( $from, $to, $val );
 263                         }
 264                         return $in;
 265                 } else {
 266                         return $in;
 267                 }
 268         }
 269
 270         /**
 271          * Gets all settings for a wiki
 272          * @param $wiki String Wiki ID of the wiki in question.
 273          * @param $suffix String The suffix of the wiki in question.
 274          * @param $params Array List of parameters. $.'key' is replaced by $value in all returned data.
 275          * @param $wikiTags Array The tags assigned to the wiki.
 276          * @return Array Array of settings requested.
 277          */
 278         public function getAll( $wiki, $suffix = null, $params = array(), $wikiTags = array() ) {
 279                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 280                 $localSettings = array();
 281                 foreach( $this->settings as $varname => $stuff ) {
 282                         $append = false;
 283                         $var = $varname;
 284                         if ( substr( $varname, 0, 1 ) == '+' ) {
 285                                 $append = true;
 286                                 $var = substr( $varname, 1 );
 287                         }
 288
 289                         $value = $this->getSetting( $varname, $wiki, $params );
 290                         if ( $append && is_array( $value ) && is_array( $GLOBALS[$var] ) )
 291                                 $value = self::arrayMerge( $value, $GLOBALS[$var] );
 292                         if ( !is_null( $value ) ) {
 293                                 $localSettings[$var] = $value;
 294                         }
 295                 }
 296                 return $localSettings;
 297         }
 298
 299         /**
 300          * Retrieves a configuration setting for a given wiki, forced to a boolean.
 301          * @param $setting String ID of the setting name to retrieve
 302          * @param $wiki String Wiki ID of the wiki in question.
 303          * @param $suffix String The suffix of the wiki in question.
 304          * @param $wikiTags Array The tags assigned to the wiki.
 305          * @return bool The value of the setting requested.
 306          */
 307         public function getBool( $setting, $wiki, $suffix = null, $wikiTags = array() ) {
 308                 return (bool)($this->get( $setting, $wiki, $suffix, array(), $wikiTags ) );
 309         }
 310
 311         /**
 312          * Retrieves an array of local databases
 313          *
 314          * @return array
 315          */
 316         function &getLocalDatabases() {
 317                 return $this->wikis;
 318         }
 319
 320         /**
 321          * Retrieves the value of a given setting, and places it in a variable passed by reference.
 322          * @param $setting String ID of the setting name to retrieve
 323          * @param $wiki String Wiki ID of the wiki in question.
 324          * @param $suffix String The suffix of the wiki in question.
 325          * @param $var array Reference The variable to insert the value into.
 326          * @param $params Array List of parameters. $.'key' is replaced by $value in all returned data.
 327          * @param $wikiTags Array The tags assigned to the wiki.
 328          */
 329         public function extractVar( $setting, $wiki, $suffix, &$var, $params = array(), $wikiTags = array() ) {
 330                 $value = $this->get( $setting, $wiki, $suffix, $params, $wikiTags );
 331                 if ( !is_null( $value ) ) {
 332                         $var = $value;
 333                 }
 334         }
 335
 336         /**
 337          * Retrieves the value of a given setting, and places it in its corresponding global variable.
 338          * @param $setting String ID of the setting name to retrieve
 339          * @param $wiki String Wiki ID of the wiki in question.
 340          * @param $suffix String The suffix of the wiki in question.
 341          * @param $params Array List of parameters. $.'key' is replaced by $value in all returned data.
 342          * @param $wikiTags Array The tags assigned to the wiki.
 343          */
 344         public function extractGlobal( $setting, $wiki, $suffix = null, $params = array(), $wikiTags = array() ) {
 345                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 346                 $this->extractGlobalSetting( $setting, $wiki, $params );
 347         }
 348
 349         /**
 350          * @param $setting string
 351          * @param $wiki string
 352          * @param $params array
 353          */
 354         public function extractGlobalSetting( $setting, $wiki, $params ) {
 355                 $value = $this->getSetting( $setting, $wiki, $params );
 356                 if ( !is_null( $value ) ) {
 357                         if (substr($setting,0,1) == '+' && is_array($value)) {
 358                                 $setting = substr($setting,1);
 359                                 if ( is_array($GLOBALS[$setting]) ) {
 360                                         $GLOBALS[$setting] = self::arrayMerge( $GLOBALS[$setting], $value );
 361                                 } else {
 362                                         $GLOBALS[$setting] = $value;
 363                                 }
 364                         } else {
 365                                 $GLOBALS[$setting] = $value;
 366                         }
 367                 }
 368         }
 369
 370         /**
 371          * Retrieves the values of all settings, and places them in their corresponding global variables.
 372          * @param $wiki String Wiki ID of the wiki in question.
 373          * @param $suffix String The suffix of the wiki in question.
 374          * @param $params Array List of parameters. $.'key' is replaced by $value in all returned data.
 375          * @param $wikiTags Array The tags assigned to the wiki.
 376          */
 377         public function extractAllGlobals( $wiki, $suffix = null, $params = array(), $wikiTags = array() ) {
 378                 $params = $this->mergeParams( $wiki, $suffix, $params, $wikiTags );
 379                 foreach ( $this->settings as $varName => $setting ) {
 380                         $this->extractGlobalSetting( $varName, $wiki, $params );
 381                 }
 382         }
 383
 384         /**
 385          * Return specific settings for $wiki
 386          * See the documentation of self::$siteParamsCallback for more in-depth
 387          * documentation about this function
 388          *
 389          * @param $wiki String
 390          * @return array
 391          */
 392         protected function getWikiParams( $wiki ){
 393                 static $default = array(
 394                         'suffix' => null,
 395                         'lang' => null,
 396                         'tags' => array(),
 397                         'params' => array(),
 398                 );
 399
 400                 if( !is_callable( $this->siteParamsCallback ) ) {
 401                         return $default;
 402                 }
 403
 404                 $ret = call_user_func_array( $this->siteParamsCallback, array( $this, $wiki ) );
 405                 # Validate the returned value
 406                 if( !is_array( $ret ) ) {
 407                         return $default;
 408                 }
 409
 410                 foreach( $default as $name => $def ){
 411                         if( !isset( $ret[$name] ) || ( is_array( $default[$name] ) && !is_array( $ret[$name] ) ) )
 412                                 $ret[$name] = $default[$name];
 413                 }
 414
 415                 return $ret;
 416         }
 417
 418         /**
 419          * Merge params between the ones passed to the function and the ones given
 420          * by self::$siteParamsCallback for backward compatibility
 421          * Values returned by self::getWikiParams() have the priority.
 422          *
 423          * @param $wiki String Wiki ID of the wiki in question.
 424          * @param $suffix String The suffix of the wiki in question.
 425          * @param $params Array List of parameters. $.'key' is replaced by $value in
 426          *                all returned data.
 427          * @param $wikiTags Array The tags assigned to the wiki.
 428          * @return array
 429          */
 430         protected function mergeParams( $wiki, $suffix, /*array*/ $params, /*array*/ $wikiTags ){
 431                 $ret = $this->getWikiParams( $wiki );
 432
 433                 if( is_null( $ret['suffix'] ) )
 434                         $ret['suffix'] = $suffix;
 435
 436                 $ret['tags'] = array_unique( array_merge( $ret['tags'], $wikiTags ) );
 437
 438                 $ret['params'] += $params;
 439
 440                 // Automatically fill that ones if needed
 441                 if( !isset( $ret['params']['lang'] ) && !is_null( $ret['lang'] ) )
 442                         $ret['params']['lang'] = $ret['lang'];
 443                 if( !isset( $ret['params']['site'] ) && !is_null( $ret['suffix'] ) )
 444                         $ret['params']['site'] = $ret['suffix'];
 445
 446                 return $ret;
 447         }
 448
 449         /**
 450          * Work out the site and language name from a database name
 451          * @param $db
 452          *
 453          * @return array
 454          */
 455         public function siteFromDB( $db ) {
 456                 // Allow override
 457                 $def = $this->getWikiParams( $db );
 458                 if( !is_null( $def['suffix'] ) && !is_null( $def['lang'] ) )
 459                         return array( $def['suffix'], $def['lang'] );
 460
 461                 $site = null;
 462                 $lang = null;
 463                 foreach ( $this->suffixes as $suffix ) {
 464                         if ( $suffix === '' ) {
 465                                 $site = '';
 466                                 $lang = $db;
 467                                 break;
 468                         } elseif ( substr( $db, -strlen( $suffix ) ) == $suffix ) {
 469                                 $site = $suffix == 'wiki' ? 'wikipedia' : $suffix;
 470                                 $lang = substr( $db, 0, strlen( $db ) - strlen( $suffix ) );
 471                                 break;
 472                         }
 473                 }
 474                 $lang = str_replace( '_', '-', $lang );
 475                 return array( $site, $lang );
 476         }
 477
 478         /**
 479          * Returns true if the given vhost is handled locally.
 480          * @param $vhost String
 481          * @return bool
 482          */
 483         public function isLocalVHost( $vhost ) {
 484                 return in_array( $vhost, $this->localVHosts );
 485         }
 486
 487         /**
 488          * Merge multiple arrays together.
 489          * On encountering duplicate keys, merge the two, but ONLY if they're arrays.
 490          * PHP's array_merge_recursive() merges ANY duplicate values into arrays,
 491          * which is not fun
 492          *
 493          * @param $array1 array
 494          *
 495          * @return array
 496          */
 497         static function arrayMerge( $array1/* ... */ ) {
 498                 $out = $array1;
 499                 for( $i = 1; $i < func_num_args(); $i++ ) {
 500                         foreach( func_get_arg( $i ) as $key => $value ) {
 501                                 if ( isset($out[$key]) && is_array($out[$key]) && is_array($value) ) {
 502                                         $out[$key] = self::arrayMerge( $out[$key], $value );
 503                                 } elseif ( !isset($out[$key]) || !$out[$key] && !is_numeric($key) ) {
 504                                         // Values that evaluate to true given precedence, for the primary purpose of merging permissions arrays.
 505                                         $out[$key] = $value;
 506                                 } elseif ( is_numeric( $key ) ) {
 507                                         $out[] = $value;
 508                                 }
 509                         }
 510                 }
 511
 512                 return $out;
 513         }
 514
 515         public function loadFullData() {
 516                 if ($this->fullLoadCallback && !$this->fullLoadDone) {
 517                         call_user_func( $this->fullLoadCallback, $this );
 518                         $this->fullLoadDone = true;
 519                 }
 520         }
 521 }