includes/Message.php

   1 <?php
   2 /**
   3  * Fetching and processing of interface messages.
   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  * @author Niklas Laxström
  22  */
  23
  24 /**
  25  * The Message class provides methods which fulfil two basic services:
  26  *  - fetching interface messages
  27  *  - processing messages into a variety of formats
  28  *
  29  * First implemented with MediaWiki 1.17, the Message class is intended to
  30  * replace the old wfMsg* functions that over time grew unusable.
  31  * @see https://www.mediawiki.org/wiki/Manual:Messages_API for equivalences
  32  * between old and new functions.
  33  *
  34  * You should use the wfMessage() global function which acts as a wrapper for
  35  * the Message class. The wrapper let you pass parameters as arguments.
  36  *
  37  * The most basic usage cases would be:
  38  *
  39  * @code
  40  *     // Initialize a Message object using the 'some_key' message key
  41  *     $message = wfMessage( 'some_key' );
  42  *
  43  *     // Using two parameters those values are strings 'value1' and 'value2':
  44  *     $message = wfMessage( 'some_key',
  45  *          'value1', 'value2'
  46  *     );
  47  * @endcode
  48  *
  49  * @section message_global_fn Global function wrapper:
  50  *
  51  * Since wfMessage() returns a Message instance, you can chain its call with
  52  * a method. Some of them return a Message instance too so you can chain them.
  53  * You will find below several examples of wfMessage() usage.
  54  *
  55  * Fetching a message text for interface message:
  56  *
  57  * @code
  58  *    $button = Xml::button(
  59  *         wfMessage( 'submit' )->text()
  60  *    );
  61  * @endcode
  62  *
  63  * A Message instance can be passed parameters after it has been constructed,
  64  * use the params() method to do so:
  65  *
  66  * @code
  67  *     wfMessage( 'welcome-to' )
  68  *         ->params( $wgSitename )
  69  *         ->text();
  70  * @endcode
  71  *
  72  * {{GRAMMAR}} and friends work correctly:
  73  *
  74  * @code
  75  *    wfMessage( 'are-friends',
  76  *        $user, $friend
  77  *    );
  78  *    wfMessage( 'bad-message' )
  79  *         ->rawParams( '<script>...</script>' )
  80  *         ->escaped();
  81  * @endcode
  82  *
  83  * @section message_language Changing language:
  84  *
  85  * Messages can be requested in a different language or in whatever current
  86  * content language is being used. The methods are:
  87  *     - Message->inContentLanguage()
  88  *     - Message->inLanguage()
  89  *
  90  * Sometimes the message text ends up in the database, so content language is
  91  * needed:
  92  *
  93  * @code
  94  *    wfMessage( 'file-log',
  95  *        $user, $filename
  96  *    )->inContentLanguage()->text();
  97  * @endcode
  98  *
  99  * Checking whether a message exists:
 100  *
 101  * @code
 102  *    wfMessage( 'mysterious-message' )->exists()
 103  *    // returns a boolean whether the 'mysterious-message' key exist.
 104  * @endcode
 105  *
 106  * If you want to use a different language:
 107  *
 108  * @code
 109  *    $userLanguage = $user->getOption( 'language' );
 110  *    wfMessage( 'email-header' )
 111  *         ->inLanguage( $userLanguage )
 112  *         ->plain();
 113  * @endcode
 114  *
 115  * @note You can parse the text only in the content or interface languages
 116  *
 117  * @section message_compare_old Comparison with old wfMsg* functions:
 118  *
 119  * Use full parsing:
 120  *
 121  * @code
 122  *     // old style:
 123  *     wfMsgExt( 'key', array( 'parseinline' ), 'apple' );
 124  *     // new style:
 125  *     wfMessage( 'key', 'apple' )->parse();
 126  * @endcode
 127  *
 128  * Parseinline is used because it is more useful when pre-building HTML.
 129  * In normal use it is better to use OutputPage::(add|wrap)WikiMsg.
 130  *
 131  * Places where HTML cannot be used. {{-transformation is done.
 132  * @code
 133  *     // old style:
 134  *     wfMsgExt( 'key', array( 'parsemag' ), 'apple', 'pear' );
 135  *     // new style:
 136  *     wfMessage( 'key', 'apple', 'pear' )->text();
 137  * @endcode
 138  *
 139  * Shortcut for escaping the message too, similar to wfMsgHTML(), but
 140  * parameters are not replaced after escaping by default.
 141  * @code
 142  *     $escaped = wfMessage( 'key' )
 143  *          ->rawParams( 'apple' )
 144  *          ->escaped();
 145  * @endcode
 146  *
 147  * @section message_appendix Appendix:
 148  *
 149  * @todo
 150  * - test, can we have tests?
 151  * - this documentation needs to be extended
 152  *
 153  * @see https://www.mediawiki.org/wiki/WfMessage()
 154  * @see https://www.mediawiki.org/wiki/New_messages_API
 155  * @see https://www.mediawiki.org/wiki/Localisation
 156  *
 157  * @since 1.17
 158  */
 159 class Message {
 160         /**
 161          * In which language to get this message. True, which is the default,
 162          * means the current interface language, false content language.
 163          */
 164         protected $interface = true;
 165
 166         /**
 167          * In which language to get this message. Overrides the $interface
 168          * variable.
 169          *
 170          * @var Language
 171          */
 172         protected $language = null;
 173
 174         /**
 175          * The message key.
 176          */
 177         protected $key;
 178
 179         /**
 180          * List of parameters which will be substituted into the message.
 181          */
 182         protected $parameters = array();
 183
 184         /**
 185          * Format for the message.
 186          * Supported formats are:
 187          * * text (transform)
 188          * * escaped (transform+htmlspecialchars)
 189          * * block-parse
 190          * * parse (default)
 191          * * plain
 192          */
 193         protected $format = 'parse';
 194
 195         /**
 196          * Whether database can be used.
 197          */
 198         protected $useDatabase = true;
 199
 200         /**
 201          * Title object to use as context
 202          */
 203         protected $title = null;
 204
 205         /**
 206          * Content object representing the message
 207          */
 208         protected $content = null;
 209
 210         /**
 211          * @var string
 212          */
 213         protected $message;
 214
 215         /**
 216          * Constructor.
 217          * @since 1.17
 218          * @param $key: message key, or array of message keys to try and use the first non-empty message for
 219          * @param array $params message parameters
 220          * @return Message: $this
 221          */
 222         public function __construct( $key, $params = array() ) {
 223                 global $wgLang;
 224                 $this->key = $key;
 225                 $this->parameters = array_values( $params );
 226                 $this->language = $wgLang;
 227         }
 228
 229         /**
 230          * Returns the message key
 231          *
 232          * @since 1.21
 233          *
 234          * @return string
 235          */
 236         public function getKey() {
 237                 return $this->key;
 238         }
 239
 240         /**
 241          * Returns the message parameters
 242          *
 243          * @since 1.21
 244          *
 245          * @return string[]
 246          */
 247         public function getParams() {
 248                 return $this->parameters;
 249         }
 250
 251         /**
 252          * Returns the message format
 253          *
 254          * @since 1.21
 255          *
 256          * @return string
 257          */
 258         public function getFormat() {
 259                 return $this->format;
 260         }
 261
 262         /**
 263          * Factory function that is just wrapper for the real constructor. It is
 264          * intended to be used instead of the real constructor, because it allows
 265          * chaining method calls, while new objects don't.
 266          * @since 1.17
 267          * @param string $key message key
 268          * @param Varargs: parameters as Strings
 269          * @return Message: $this
 270          */
 271         public static function newFromKey( $key /*...*/ ) {
 272                 $params = func_get_args();
 273                 array_shift( $params );
 274                 return new self( $key, $params );
 275         }
 276
 277         /**
 278          * Factory function accepting multiple message keys and returning a message instance
 279          * for the first message which is non-empty. If all messages are empty then an
 280          * instance of the first message key is returned.
 281          * @since 1.18
 282          * @param Varargs: message keys (or first arg as an array of all the message keys)
 283          * @return Message: $this
 284          */
 285         public static function newFallbackSequence( /*...*/ ) {
 286                 $keys = func_get_args();
 287                 if ( func_num_args() == 1 ) {
 288                         if ( is_array( $keys[0] ) ) {
 289                                 // Allow an array to be passed as the first argument instead
 290                                 $keys = array_values( $keys[0] );
 291                         } else {
 292                                 // Optimize a single string to not need special fallback handling
 293                                 $keys = $keys[0];
 294                         }
 295                 }
 296                 return new self( $keys );
 297         }
 298
 299         /**
 300          * Adds parameters to the parameter list of this message.
 301          * @since 1.17
 302          * @param Varargs: parameters as Strings, or a single argument that is an array of Strings
 303          * @return Message: $this
 304          */
 305         public function params( /*...*/ ) {
 306                 $args = func_get_args();
 307                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 308                         $args = $args[0];
 309                 }
 310                 $args_values = array_values( $args );
 311                 $this->parameters = array_merge( $this->parameters, $args_values );
 312                 return $this;
 313         }
 314
 315         /**
 316          * Add parameters that are substituted after parsing or escaping.
 317          * In other words the parsing process cannot access the contents
 318          * of this type of parameter, and you need to make sure it is
 319          * sanitized beforehand.  The parser will see "$n", instead.
 320          * @since 1.17
 321          * @param Varargs: raw parameters as Strings (or single argument that is an array of raw parameters)
 322          * @return Message: $this
 323          */
 324         public function rawParams( /*...*/ ) {
 325                 $params = func_get_args();
 326                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 327                         $params = $params[0];
 328                 }
 329                 foreach( $params as $param ) {
 330                         $this->parameters[] = self::rawParam( $param );
 331                 }
 332                 return $this;
 333         }
 334
 335         /**
 336          * Add parameters that are numeric and will be passed through
 337          * Language::formatNum before substitution
 338          * @since 1.18
 339          * @param Varargs: numeric parameters (or single argument that is array of numeric parameters)
 340          * @return Message: $this
 341          */
 342         public function numParams( /*...*/ ) {
 343                 $params = func_get_args();
 344                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 345                         $params = $params[0];
 346                 }
 347                 foreach( $params as $param ) {
 348                         $this->parameters[] = self::numParam( $param );
 349                 }
 350                 return $this;
 351         }
 352
 353         /**
 354          * Set the language and the title from a context object
 355          * @since 1.19
 356          * @param $context IContextSource
 357          * @return Message: $this
 358          */
 359         public function setContext( IContextSource $context ) {
 360                 $this->inLanguage( $context->getLanguage() );
 361                 $this->title( $context->getTitle() );
 362                 $this->interface = true;
 363
 364                 return $this;
 365         }
 366
 367         /**
 368          * Request the message in any language that is supported.
 369          * As a side effect interface message status is unconditionally
 370          * turned off.
 371          * @since 1.17
 372          * @param $lang Mixed: language code or Language object.
 373          * @throws MWException
 374          * @return Message: $this
 375          */
 376         public function inLanguage( $lang ) {
 377                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 378                         $this->language = $lang;
 379                 } elseif ( is_string( $lang ) ) {
 380                         if( $this->language->getCode() != $lang ) {
 381                                 $this->language = Language::factory( $lang );
 382                         }
 383                 } else {
 384                         $type = gettype( $lang );
 385                         throw new MWException( __METHOD__ . " must be "
 386                                 . "passed a String or Language object; $type given"
 387                         );
 388                 }
 389                 $this->interface = false;
 390                 return $this;
 391         }
 392
 393         /**
 394          * Request the message in the wiki's content language,
 395          * unless it is disabled for this message.
 396          * @since 1.17
 397          * @see $wgForceUIMsgAsContentMsg
 398          * @return Message: $this
 399          */
 400         public function inContentLanguage() {
 401                 global $wgForceUIMsgAsContentMsg;
 402                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 403                         return $this;
 404                 }
 405
 406                 global $wgContLang;
 407                 $this->interface = false;
 408                 $this->language = $wgContLang;
 409                 return $this;
 410         }
 411
 412         /**
 413          * Allows manipulating the interface message flag directly.
 414          * Can be used to restore the flag after setting a language.
 415          * @param $value bool
 416          * @return Message: $this
 417          * @since 1.20
 418          */
 419         public function setInterfaceMessageFlag( $value ) {
 420                 $this->interface = (bool) $value;
 421                 return $this;
 422         }
 423
 424         /**
 425          * Enable or disable database use.
 426          * @since 1.17
 427          * @param $value Boolean
 428          * @return Message: $this
 429          */
 430         public function useDatabase( $value ) {
 431                 $this->useDatabase = (bool) $value;
 432                 return $this;
 433         }
 434
 435         /**
 436          * Set the Title object to use as context when transforming the message
 437          * @since 1.18
 438          * @param $title Title object
 439          * @return Message: $this
 440          */
 441         public function title( $title ) {
 442                 $this->title = $title;
 443                 return $this;
 444         }
 445
 446         /**
 447          * Returns the message as a Content object.
 448          * @return Content
 449          */
 450         public function content() {
 451                 if ( !$this->content ) {
 452                         $this->content = new MessageContent( $this );
 453                 }
 454
 455                 return $this->content;
 456         }
 457
 458         /**
 459          * Returns the message parsed from wikitext to HTML.
 460          * @since 1.17
 461          * @return String: HTML
 462          */
 463         public function toString() {
 464                 $string = $this->fetchMessage();
 465
 466                 if ( $string === false ) {
 467                         $key = htmlspecialchars( is_array( $this->key ) ? $this->key[0] : $this->key );
 468                         if ( $this->format === 'plain' ) {
 469                                 return '<' . $key . '>';
 470                         }
 471                         return '&lt;' . $key . '&gt;';
 472                 }
 473
 474                 # Replace $* with a list of parameters for &uselang=qqx.
 475                 if ( strpos( $string, '$*' ) !== false ) {
 476                         $paramlist = '';
 477                         if ( $this->parameters !== array() ) {
 478                                 $paramlist = ': $' . implode( ', $', range( 1, count( $this->parameters ) ) );
 479                         }
 480                         $string = str_replace( '$*', $paramlist, $string );
 481                 }
 482
 483                 # Replace parameters before text parsing
 484                 $string = $this->replaceParameters( $string, 'before' );
 485
 486                 # Maybe transform using the full parser
 487                 if( $this->format === 'parse' ) {
 488                         $string = $this->parseText( $string );
 489                         $m = array();
 490                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 491                                 $string = $m[1];
 492                         }
 493                 } elseif( $this->format === 'block-parse' ) {
 494                         $string = $this->parseText( $string );
 495                 } elseif( $this->format === 'text' ) {
 496                         $string = $this->transformText( $string );
 497                 } elseif( $this->format === 'escaped' ) {
 498                         $string = $this->transformText( $string );
 499                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 500                 }
 501
 502                 # Raw parameter replacement
 503                 $string = $this->replaceParameters( $string, 'after' );
 504
 505                 return $string;
 506         }
 507
 508         /**
 509          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 510          *     $foo = Message::get( $key );
 511          *     $string = "<abbr>$foo</abbr>";
 512          * @since 1.18
 513          * @return String
 514          */
 515         public function __toString() {
 516                 // PHP doesn't allow __toString to throw exceptions and will
 517                 // trigger a fatal error if it does. So, catch any exceptions.
 518
 519                 try {
 520                         return $this->toString();
 521                 } catch ( Exception $ex ) {
 522                         try {
 523                                 trigger_error( "Exception caught in " . __METHOD__ . " (message " . $this->key . "): "
 524                                         . $ex, E_USER_WARNING );
 525                         } catch ( Exception $ex ) {
 526                                 // Doh! Cause a fatal error after all?
 527                         }
 528
 529                         if ( $this->format === 'plain' ) {
 530                                 return '<' . $this->key . '>';
 531                         }
 532                         return '&lt;' . $this->key . '&gt;';
 533                 }
 534         }
 535
 536         /**
 537          * Fully parse the text from wikitext to HTML
 538          * @since 1.17
 539          * @return String parsed HTML
 540          */
 541         public function parse() {
 542                 $this->format = 'parse';
 543                 return $this->toString();
 544         }
 545
 546         /**
 547          * Returns the message text. {{-transformation is done.
 548          * @since 1.17
 549          * @return String: Unescaped message text.
 550          */
 551         public function text() {
 552                 $this->format = 'text';
 553                 return $this->toString();
 554         }
 555
 556         /**
 557          * Returns the message text as-is, only parameters are substituted.
 558          * @since 1.17
 559          * @return String: Unescaped untransformed message text.
 560          */
 561         public function plain() {
 562                 $this->format = 'plain';
 563                 return $this->toString();
 564         }
 565
 566         /**
 567          * Returns the parsed message text which is always surrounded by a block element.
 568          * @since 1.17
 569          * @return String: HTML
 570          */
 571         public function parseAsBlock() {
 572                 $this->format = 'block-parse';
 573                 return $this->toString();
 574         }
 575
 576         /**
 577          * Returns the message text. {{-transformation is done and the result
 578          * is escaped excluding any raw parameters.
 579          * @since 1.17
 580          * @return String: Escaped message text.
 581          */
 582         public function escaped() {
 583                 $this->format = 'escaped';
 584                 return $this->toString();
 585         }
 586
 587         /**
 588          * Check whether a message key has been defined currently.
 589          * @since 1.17
 590          * @return Bool: true if it is and false if not.
 591          */
 592         public function exists() {
 593                 return $this->fetchMessage() !== false;
 594         }
 595
 596         /**
 597          * Check whether a message does not exist, or is an empty string
 598          * @since 1.18
 599          * @return Bool: true if is is and false if not
 600          * @todo FIXME: Merge with isDisabled()?
 601          */
 602         public function isBlank() {
 603                 $message = $this->fetchMessage();
 604                 return $message === false || $message === '';
 605         }
 606
 607         /**
 608          * Check whether a message does not exist, is an empty string, or is "-"
 609          * @since 1.18
 610          * @return Bool: true if it is and false if not
 611          */
 612         public function isDisabled() {
 613                 $message = $this->fetchMessage();
 614                 return $message === false || $message === '' || $message === '-';
 615         }
 616
 617         /**
 618          * @since 1.17
 619          * @param $value
 620          * @return array
 621          */
 622         public static function rawParam( $value ) {
 623                 return array( 'raw' => $value );
 624         }
 625
 626         /**
 627          * @since 1.18
 628          * @param $value
 629          * @return array
 630          */
 631         public static function numParam( $value ) {
 632                 return array( 'num' => $value );
 633         }
 634
 635         /**
 636          * Substitutes any parameters into the message text.
 637          * @since 1.17
 638          * @param string $message the message text
 639          * @param string $type either before or after
 640          * @return String
 641          */
 642         protected function replaceParameters( $message, $type = 'before' ) {
 643                 $replacementKeys = array();
 644                 foreach( $this->parameters as $n => $param ) {
 645                         list( $paramType, $value ) = $this->extractParam( $param );
 646                         if ( $type === $paramType ) {
 647                                 $replacementKeys['$' . ($n + 1)] = $value;
 648                         }
 649                 }
 650                 $message = strtr( $message, $replacementKeys );
 651                 return $message;
 652         }
 653
 654         /**
 655          * Extracts the parameter type and preprocessed the value if needed.
 656          * @since 1.18
 657          * @param string|array $param Parameter as defined in this class.
 658          * @return Tuple(type, value)
 659          */
 660         protected function extractParam( $param ) {
 661                 if ( is_array( $param ) && isset( $param['raw'] ) ) {
 662                         return array( 'after', $param['raw'] );
 663                 } elseif ( is_array( $param ) && isset( $param['num'] ) ) {
 664                         // Replace number params always in before step for now.
 665                         // No support for combined raw and num params
 666                         return array( 'before', $this->language->formatNum( $param['num'] ) );
 667                 } elseif ( !is_array( $param ) ) {
 668                         return array( 'before', $param );
 669                 } else {
 670                         trigger_error(
 671                                 "Invalid message parameter: " . htmlspecialchars( serialize( $param ) ),
 672                                 E_USER_WARNING
 673                         );
 674                         return array( 'before', '[INVALID]' );
 675                 }
 676         }
 677
 678         /**
 679          * Wrapper for what ever method we use to parse wikitext.
 680          * @since 1.17
 681          * @param string $string Wikitext message contents
 682          * @return string Wikitext parsed into HTML
 683          */
 684         protected function parseText( $string ) {
 685                 $out = MessageCache::singleton()->parse( $string, $this->title, /*linestart*/true, $this->interface, $this->language );
 686                 return is_object( $out ) ? $out->getText() : $out;
 687         }
 688
 689         /**
 690          * Wrapper for what ever method we use to {{-transform wikitext.
 691          * @since 1.17
 692          * @param string $string Wikitext message contents
 693          * @return string Wikitext with {{-constructs replaced with their values.
 694          */
 695         protected function transformText( $string ) {
 696                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language, $this->title );
 697         }
 698
 699         /**
 700          * Wrapper for what ever method we use to get message contents
 701          * @since 1.17
 702          * @throws MWException
 703          * @return string
 704          */
 705         protected function fetchMessage() {
 706                 if ( !isset( $this->message ) ) {
 707                         $cache = MessageCache::singleton();
 708                         if ( is_array( $this->key ) ) {
 709                                 if ( !count( $this->key ) ) {
 710                                         throw new MWException( "Given empty message key array." );
 711                                 }
 712                                 foreach ( $this->key as $key ) {
 713                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 714                                         if ( $message !== false && $message !== '' ) {
 715                                                 break;
 716                                         }
 717                                 }
 718                                 $this->message = $message;
 719                         } else {
 720                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 721                         }
 722                 }
 723                 return $this->message;
 724         }
 725
 726 }
 727
 728 /**
 729  * Variant of the Message class.
 730  *
 731  * Rather than treating the message key as a lookup
 732  * value (which is passed to the MessageCache and
 733  * translated as necessary), a RawMessage key is
 734  * treated as the actual message.
 735  *
 736  * All other functionality (parsing, escaping, etc.)
 737  * is preserved.
 738  *
 739  * @since 1.21
 740  */
 741 class RawMessage extends Message {
 742         /**
 743          * Call the parent constructor, then store the key as
 744          * the message.
 745          *
 746          * @param string $key Message to use
 747          * @param array $params Parameters for the message
 748          * @see Message::__construct
 749          */
 750         public function __construct( $key, $params = array() ) {
 751                 parent::__construct( $key, $params );
 752                 // The key is the message.
 753                 $this->message = $key;
 754         }
 755
 756         /**
 757          * Fetch the message (in this case, the key).
 758          *
 759          * @return string
 760          */
 761         public function fetchMessage() {
 762                 // Just in case the message is unset somewhere.
 763                 if( !isset( $this->message ) ) {
 764                         $this->message = $this->key;
 765                 }
 766                 return $this->message;
 767         }
 768 }