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 fullfil 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 intented 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          * @var string
 207          */
 208         protected $message;
 209
 210         /**
 211          * Constructor.
 212          * @since 1.17
 213          * @param $key: message key, or array of message keys to try and use the first non-empty message for
 214          * @param $params Array message parameters
 215          * @return Message: $this
 216          */
 217         public function __construct( $key, $params = array() ) {
 218                 global $wgLang;
 219                 $this->key = $key;
 220                 $this->parameters = array_values( $params );
 221                 $this->language = $wgLang;
 222         }
 223
 224         /**
 225          * Factory function that is just wrapper for the real constructor. It is
 226          * intented to be used instead of the real constructor, because it allows
 227          * chaining method calls, while new objects don't.
 228          * @since 1.17
 229          * @param $key String: message key
 230          * @param Varargs: parameters as Strings
 231          * @return Message: $this
 232          */
 233         public static function newFromKey( $key /*...*/ ) {
 234                 $params = func_get_args();
 235                 array_shift( $params );
 236                 return new self( $key, $params );
 237         }
 238
 239         /**
 240          * Factory function accepting multiple message keys and returning a message instance
 241          * for the first message which is non-empty. If all messages are empty then an
 242          * instance of the first message key is returned.
 243          * @since 1.18
 244          * @param Varargs: message keys (or first arg as an array of all the message keys)
 245          * @return Message: $this
 246          */
 247         public static function newFallbackSequence( /*...*/ ) {
 248                 $keys = func_get_args();
 249                 if ( func_num_args() == 1 ) {
 250                         if ( is_array($keys[0]) ) {
 251                                 // Allow an array to be passed as the first argument instead
 252                                 $keys = array_values($keys[0]);
 253                         } else {
 254                                 // Optimize a single string to not need special fallback handling
 255                                 $keys = $keys[0];
 256                         }
 257                 }
 258                 return new self( $keys );
 259         }
 260
 261         /**
 262          * Adds parameters to the parameter list of this message.
 263          * @since 1.17
 264          * @param Varargs: parameters as Strings, or a single argument that is an array of Strings
 265          * @return Message: $this
 266          */
 267         public function params( /*...*/ ) {
 268                 $args = func_get_args();
 269                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 270                         $args = $args[0];
 271                 }
 272                 $args_values = array_values( $args );
 273                 $this->parameters = array_merge( $this->parameters, $args_values );
 274                 return $this;
 275         }
 276
 277         /**
 278          * Add parameters that are substituted after parsing or escaping.
 279          * In other words the parsing process cannot access the contents
 280          * of this type of parameter, and you need to make sure it is
 281          * sanitized beforehand.  The parser will see "$n", instead.
 282          * @since 1.17
 283          * @param Varargs: raw parameters as Strings (or single argument that is an array of raw parameters)
 284          * @return Message: $this
 285          */
 286         public function rawParams( /*...*/ ) {
 287                 $params = func_get_args();
 288                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 289                         $params = $params[0];
 290                 }
 291                 foreach( $params as $param ) {
 292                         $this->parameters[] = self::rawParam( $param );
 293                 }
 294                 return $this;
 295         }
 296
 297         /**
 298          * Add parameters that are numeric and will be passed through
 299          * Language::formatNum before substitution
 300          * @since 1.18
 301          * @param Varargs: numeric parameters (or single argument that is array of numeric parameters)
 302          * @return Message: $this
 303          */
 304         public function numParams( /*...*/ ) {
 305                 $params = func_get_args();
 306                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 307                         $params = $params[0];
 308                 }
 309                 foreach( $params as $param ) {
 310                         $this->parameters[] = self::numParam( $param );
 311                 }
 312                 return $this;
 313         }
 314
 315         /**
 316          * Set the language and the title from a context object
 317          * @since 1.19
 318          * @param $context IContextSource
 319          * @return Message: $this
 320          */
 321         public function setContext( IContextSource $context ) {
 322                 $this->inLanguage( $context->getLanguage() );
 323                 $this->title( $context->getTitle() );
 324                 $this->interface = true;
 325
 326                 return $this;
 327         }
 328
 329         /**
 330          * Request the message in any language that is supported.
 331          * As a side effect interface message status is unconditionally
 332          * turned off.
 333          * @since 1.17
 334          * @param $lang Mixed: language code or Language object.
 335          * @return Message: $this
 336          */
 337         public function inLanguage( $lang ) {
 338                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 339                         $this->language = $lang;
 340                 } elseif ( is_string( $lang ) ) {
 341                         if( $this->language->getCode() != $lang ) {
 342                                 $this->language = Language::factory( $lang );
 343                         }
 344                 } else {
 345                         $type = gettype( $lang );
 346                         throw new MWException( __METHOD__ . " must be "
 347                                 . "passed a String or Language object; $type given"
 348                         );
 349                 }
 350                 $this->interface = false;
 351                 return $this;
 352         }
 353
 354         /**
 355          * Request the message in the wiki's content language,
 356          * unless it is disabled for this message.
 357          * @since 1.17
 358          * @see $wgForceUIMsgAsContentMsg
 359          * @return Message: $this
 360          */
 361         public function inContentLanguage() {
 362                 global $wgForceUIMsgAsContentMsg;
 363                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 364                         return $this;
 365                 }
 366
 367                 global $wgContLang;
 368                 $this->interface = false;
 369                 $this->language = $wgContLang;
 370                 return $this;
 371         }
 372
 373         /**
 374          * Allows manipulating the interface message flag directly.
 375          * Can be used to restore the flag after setting a language.
 376          * @param $value bool
 377          * @return Message: $this
 378          * @since 1.20
 379          */
 380         public function setInterfaceMessageFlag( $value ) {
 381                 $this->interface = (bool) $value;
 382                 return $this;
 383         }
 384
 385         /**
 386          * Enable or disable database use.
 387          * @since 1.17
 388          * @param $value Boolean
 389          * @return Message: $this
 390          */
 391         public function useDatabase( $value ) {
 392                 $this->useDatabase = (bool) $value;
 393                 return $this;
 394         }
 395
 396         /**
 397          * Set the Title object to use as context when transforming the message
 398          * @since 1.18
 399          * @param $title Title object
 400          * @return Message: $this
 401          */
 402         public function title( $title ) {
 403                 $this->title = $title;
 404                 return $this;
 405         }
 406
 407         /**
 408          * Returns the message parsed from wikitext to HTML.
 409          * @since 1.17
 410          * @return String: HTML
 411          */
 412         public function toString() {
 413                 $string = $this->fetchMessage();
 414
 415                 if ( $string === false ) {
 416                         $key =  htmlspecialchars( is_array( $this->key ) ? $this->key[0] : $this->key );
 417                         if ( $this->format === 'plain' ) {
 418                                 return '<' . $key . '>';
 419                         }
 420                         return '&lt;' . $key . '&gt;';
 421                 }
 422
 423                 # Replace parameters before text parsing
 424                 $string = $this->replaceParameters( $string, 'before' );
 425
 426                 # Maybe transform using the full parser
 427                 if( $this->format === 'parse' ) {
 428                         $string = $this->parseText( $string );
 429                         $m = array();
 430                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 431                                 $string = $m[1];
 432                         }
 433                 } elseif( $this->format === 'block-parse' ){
 434                         $string = $this->parseText( $string );
 435                 } elseif( $this->format === 'text' ){
 436                         $string = $this->transformText( $string );
 437                 } elseif( $this->format === 'escaped' ){
 438                         $string = $this->transformText( $string );
 439                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 440                 }
 441
 442                 # Raw parameter replacement
 443                 $string = $this->replaceParameters( $string, 'after' );
 444
 445                 return $string;
 446         }
 447
 448         /**
 449          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 450          *     $foo = Message::get($key);
 451          *     $string = "<abbr>$foo</abbr>";
 452          * @since 1.18
 453          * @return String
 454          */
 455         public function __toString() {
 456                 return $this->toString();
 457         }
 458
 459         /**
 460          * Fully parse the text from wikitext to HTML
 461          * @since 1.17
 462          * @return String parsed HTML
 463          */
 464         public function parse() {
 465                 $this->format = 'parse';
 466                 return $this->toString();
 467         }
 468
 469         /**
 470          * Returns the message text. {{-transformation is done.
 471          * @since 1.17
 472          * @return String: Unescaped message text.
 473          */
 474         public function text() {
 475                 $this->format = 'text';
 476                 return $this->toString();
 477         }
 478
 479         /**
 480          * Returns the message text as-is, only parameters are subsituted.
 481          * @since 1.17
 482          * @return String: Unescaped untransformed message text.
 483          */
 484         public function plain() {
 485                 $this->format = 'plain';
 486                 return $this->toString();
 487         }
 488
 489         /**
 490          * Returns the parsed message text which is always surrounded by a block element.
 491          * @since 1.17
 492          * @return String: HTML
 493          */
 494         public function parseAsBlock() {
 495                 $this->format = 'block-parse';
 496                 return $this->toString();
 497         }
 498
 499         /**
 500          * Returns the message text. {{-transformation is done and the result
 501          * is escaped excluding any raw parameters.
 502          * @since 1.17
 503          * @return String: Escaped message text.
 504          */
 505         public function escaped() {
 506                 $this->format = 'escaped';
 507                 return $this->toString();
 508         }
 509
 510         /**
 511          * Check whether a message key has been defined currently.
 512          * @since 1.17
 513          * @return Bool: true if it is and false if not.
 514          */
 515         public function exists() {
 516                 return $this->fetchMessage() !== false;
 517         }
 518
 519         /**
 520          * Check whether a message does not exist, or is an empty string
 521          * @since 1.18
 522          * @return Bool: true if is is and false if not
 523          * @todo FIXME: Merge with isDisabled()?
 524          */
 525         public function isBlank() {
 526                 $message = $this->fetchMessage();
 527                 return $message === false || $message === '';
 528         }
 529
 530         /**
 531          * Check whether a message does not exist, is an empty string, or is "-"
 532          * @since 1.18
 533          * @return Bool: true if it is and false if not
 534          */
 535         public function isDisabled() {
 536                 $message = $this->fetchMessage();
 537                 return $message === false || $message === '' || $message === '-';
 538         }
 539
 540         /**
 541          * @since 1.17
 542          * @param $value
 543          * @return array
 544          */
 545         public static function rawParam( $value ) {
 546                 return array( 'raw' => $value );
 547         }
 548
 549         /**
 550          * @since 1.18
 551          * @param $value
 552          * @return array
 553          */
 554         public static function numParam( $value ) {
 555                 return array( 'num' => $value );
 556         }
 557
 558         /**
 559          * Substitutes any paramaters into the message text.
 560          * @since 1.17
 561          * @param $message String: the message text
 562          * @param $type String: either before or after
 563          * @return String
 564          */
 565         protected function replaceParameters( $message, $type = 'before' ) {
 566                 $replacementKeys = array();
 567                 foreach( $this->parameters as $n => $param ) {
 568                         list( $paramType, $value ) = $this->extractParam( $param );
 569                         if ( $type === $paramType ) {
 570                                 $replacementKeys['$' . ($n + 1)] = $value;
 571                         }
 572                 }
 573                 $message = strtr( $message, $replacementKeys );
 574                 return $message;
 575         }
 576
 577         /**
 578          * Extracts the parameter type and preprocessed the value if needed.
 579          * @since 1.18
 580          * @param $param String|Array: Parameter as defined in this class.
 581          * @return Tuple(type, value)
 582          * @throws MWException
 583          */
 584         protected function extractParam( $param ) {
 585                 if ( is_array( $param ) && isset( $param['raw'] ) ) {
 586                         return array( 'after', $param['raw'] );
 587                 } elseif ( is_array( $param ) && isset( $param['num'] ) ) {
 588                         // Replace number params always in before step for now.
 589                         // No support for combined raw and num params
 590                         return array( 'before', $this->language->formatNum( $param['num'] ) );
 591                 } elseif ( !is_array( $param ) ) {
 592                         return array( 'before', $param );
 593                 } else {
 594                         throw new MWException( "Invalid message parameter" );
 595                 }
 596         }
 597
 598         /**
 599          * Wrapper for what ever method we use to parse wikitext.
 600          * @since 1.17
 601          * @param $string String: Wikitext message contents
 602          * @return string Wikitext parsed into HTML
 603          */
 604         protected function parseText( $string ) {
 605                 return MessageCache::singleton()->parse( $string, $this->title, /*linestart*/true, $this->interface, $this->language )->getText();
 606         }
 607
 608         /**
 609          * Wrapper for what ever method we use to {{-transform wikitext.
 610          * @since 1.17
 611          * @param $string String: Wikitext message contents
 612          * @return string Wikitext with {{-constructs replaced with their values.
 613          */
 614         protected function transformText( $string ) {
 615                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language, $this->title );
 616         }
 617
 618         /**
 619          * Wrapper for what ever method we use to get message contents
 620          * @since 1.17
 621          * @return string
 622          */
 623         protected function fetchMessage() {
 624                 if ( !isset( $this->message ) ) {
 625                         $cache = MessageCache::singleton();
 626                         if ( is_array( $this->key ) ) {
 627                                 if ( !count( $this->key ) ) {
 628                                         throw new MWException( "Given empty message key array." );
 629                                 }
 630                                 foreach ( $this->key as $key ) {
 631                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 632                                         if ( $message !== false && $message !== '' ) {
 633                                                 break;
 634                                         }
 635                                 }
 636                                 $this->message = $message;
 637                         } else {
 638                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 639                         }
 640                 }
 641                 return $this->message;
 642         }
 643
 644 }