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          * 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 $params Array 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          * Factory function that is just wrapper for the real constructor. It is
 231          * intented to be used instead of the real constructor, because it allows
 232          * chaining method calls, while new objects don't.
 233          * @since 1.17
 234          * @param $key String: message key
 235          * @param Varargs: parameters as Strings
 236          * @return Message: $this
 237          */
 238         public static function newFromKey( $key /*...*/ ) {
 239                 $params = func_get_args();
 240                 array_shift( $params );
 241                 return new self( $key, $params );
 242         }
 243
 244         /**
 245          * Factory function accepting multiple message keys and returning a message instance
 246          * for the first message which is non-empty. If all messages are empty then an
 247          * instance of the first message key is returned.
 248          * @since 1.18
 249          * @param Varargs: message keys (or first arg as an array of all the message keys)
 250          * @return Message: $this
 251          */
 252         public static function newFallbackSequence( /*...*/ ) {
 253                 $keys = func_get_args();
 254                 if ( func_num_args() == 1 ) {
 255                         if ( is_array($keys[0]) ) {
 256                                 // Allow an array to be passed as the first argument instead
 257                                 $keys = array_values($keys[0]);
 258                         } else {
 259                                 // Optimize a single string to not need special fallback handling
 260                                 $keys = $keys[0];
 261                         }
 262                 }
 263                 return new self( $keys );
 264         }
 265
 266         /**
 267          * Adds parameters to the parameter list of this message.
 268          * @since 1.17
 269          * @param Varargs: parameters as Strings, or a single argument that is an array of Strings
 270          * @return Message: $this
 271          */
 272         public function params( /*...*/ ) {
 273                 $args = func_get_args();
 274                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 275                         $args = $args[0];
 276                 }
 277                 $args_values = array_values( $args );
 278                 $this->parameters = array_merge( $this->parameters, $args_values );
 279                 return $this;
 280         }
 281
 282         /**
 283          * Add parameters that are substituted after parsing or escaping.
 284          * In other words the parsing process cannot access the contents
 285          * of this type of parameter, and you need to make sure it is
 286          * sanitized beforehand.  The parser will see "$n", instead.
 287          * @since 1.17
 288          * @param Varargs: raw parameters as Strings (or single argument that is an array of raw parameters)
 289          * @return Message: $this
 290          */
 291         public function rawParams( /*...*/ ) {
 292                 $params = func_get_args();
 293                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 294                         $params = $params[0];
 295                 }
 296                 foreach( $params as $param ) {
 297                         $this->parameters[] = self::rawParam( $param );
 298                 }
 299                 return $this;
 300         }
 301
 302         /**
 303          * Add parameters that are numeric and will be passed through
 304          * Language::formatNum before substitution
 305          * @since 1.18
 306          * @param Varargs: numeric parameters (or single argument that is array of numeric parameters)
 307          * @return Message: $this
 308          */
 309         public function numParams( /*...*/ ) {
 310                 $params = func_get_args();
 311                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 312                         $params = $params[0];
 313                 }
 314                 foreach( $params as $param ) {
 315                         $this->parameters[] = self::numParam( $param );
 316                 }
 317                 return $this;
 318         }
 319
 320         /**
 321          * Set the language and the title from a context object
 322          * @since 1.19
 323          * @param $context IContextSource
 324          * @return Message: $this
 325          */
 326         public function setContext( IContextSource $context ) {
 327                 $this->inLanguage( $context->getLanguage() );
 328                 $this->title( $context->getTitle() );
 329                 $this->interface = true;
 330
 331                 return $this;
 332         }
 333
 334         /**
 335          * Request the message in any language that is supported.
 336          * As a side effect interface message status is unconditionally
 337          * turned off.
 338          * @since 1.17
 339          * @param $lang Mixed: language code or Language object.
 340          * @return Message: $this
 341          */
 342         public function inLanguage( $lang ) {
 343                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 344                         $this->language = $lang;
 345                 } elseif ( is_string( $lang ) ) {
 346                         if( $this->language->getCode() != $lang ) {
 347                                 $this->language = Language::factory( $lang );
 348                         }
 349                 } else {
 350                         $type = gettype( $lang );
 351                         throw new MWException( __METHOD__ . " must be "
 352                                 . "passed a String or Language object; $type given"
 353                         );
 354                 }
 355                 $this->interface = false;
 356                 return $this;
 357         }
 358
 359         /**
 360          * Request the message in the wiki's content language,
 361          * unless it is disabled for this message.
 362          * @since 1.17
 363          * @see $wgForceUIMsgAsContentMsg
 364          * @return Message: $this
 365          */
 366         public function inContentLanguage() {
 367                 global $wgForceUIMsgAsContentMsg;
 368                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 369                         return $this;
 370                 }
 371
 372                 global $wgContLang;
 373                 $this->interface = false;
 374                 $this->language = $wgContLang;
 375                 return $this;
 376         }
 377
 378         /**
 379          * Allows manipulating the interface message flag directly.
 380          * Can be used to restore the flag after setting a language.
 381          * @param $value bool
 382          * @return Message: $this
 383          * @since 1.20
 384          */
 385         public function setInterfaceMessageFlag( $value ) {
 386                 $this->interface = (bool) $value;
 387                 return $this;
 388         }
 389
 390         /**
 391          * Enable or disable database use.
 392          * @since 1.17
 393          * @param $value Boolean
 394          * @return Message: $this
 395          */
 396         public function useDatabase( $value ) {
 397                 $this->useDatabase = (bool) $value;
 398                 return $this;
 399         }
 400
 401         /**
 402          * Set the Title object to use as context when transforming the message
 403          * @since 1.18
 404          * @param $title Title object
 405          * @return Message: $this
 406          */
 407         public function title( $title ) {
 408                 $this->title = $title;
 409                 return $this;
 410         }
 411
 412         /**
 413          * Returns the message as a Content object.
 414          * @return Content
 415          */
 416         public function content() {
 417                 if ( !$this->content ) {
 418                         $this->content = new MessageContent( $this->key );
 419                 }
 420
 421                 return $this->content;
 422         }
 423
 424         /**
 425          * Returns the message parsed from wikitext to HTML.
 426          * @since 1.17
 427          * @return String: HTML
 428          */
 429         public function toString() {
 430                 $string = $this->fetchMessage();
 431
 432                 if ( $string === false ) {
 433                         $key =  htmlspecialchars( is_array( $this->key ) ? $this->key[0] : $this->key );
 434                         if ( $this->format === 'plain' ) {
 435                                 return '<' . $key . '>';
 436                         }
 437                         return '&lt;' . $key . '&gt;';
 438                 }
 439
 440                 # Replace parameters before text parsing
 441                 $string = $this->replaceParameters( $string, 'before' );
 442
 443                 # Maybe transform using the full parser
 444                 if( $this->format === 'parse' ) {
 445                         $string = $this->parseText( $string );
 446                         $m = array();
 447                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 448                                 $string = $m[1];
 449                         }
 450                 } elseif( $this->format === 'block-parse' ){
 451                         $string = $this->parseText( $string );
 452                 } elseif( $this->format === 'text' ){
 453                         $string = $this->transformText( $string );
 454                 } elseif( $this->format === 'escaped' ){
 455                         $string = $this->transformText( $string );
 456                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 457                 }
 458
 459                 # Raw parameter replacement
 460                 $string = $this->replaceParameters( $string, 'after' );
 461
 462                 return $string;
 463         }
 464
 465         /**
 466          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 467          *     $foo = Message::get($key);
 468          *     $string = "<abbr>$foo</abbr>";
 469          * @since 1.18
 470          * @return String
 471          */
 472         public function __toString() {
 473                 return $this->toString();
 474         }
 475
 476         /**
 477          * Fully parse the text from wikitext to HTML
 478          * @since 1.17
 479          * @return String parsed HTML
 480          */
 481         public function parse() {
 482                 $this->format = 'parse';
 483                 return $this->toString();
 484         }
 485
 486         /**
 487          * Returns the message text. {{-transformation is done.
 488          * @since 1.17
 489          * @return String: Unescaped message text.
 490          */
 491         public function text() {
 492                 $this->format = 'text';
 493                 return $this->toString();
 494         }
 495
 496         /**
 497          * Returns the message text as-is, only parameters are subsituted.
 498          * @since 1.17
 499          * @return String: Unescaped untransformed message text.
 500          */
 501         public function plain() {
 502                 $this->format = 'plain';
 503                 return $this->toString();
 504         }
 505
 506         /**
 507          * Returns the parsed message text which is always surrounded by a block element.
 508          * @since 1.17
 509          * @return String: HTML
 510          */
 511         public function parseAsBlock() {
 512                 $this->format = 'block-parse';
 513                 return $this->toString();
 514         }
 515
 516         /**
 517          * Returns the message text. {{-transformation is done and the result
 518          * is escaped excluding any raw parameters.
 519          * @since 1.17
 520          * @return String: Escaped message text.
 521          */
 522         public function escaped() {
 523                 $this->format = 'escaped';
 524                 return $this->toString();
 525         }
 526
 527         /**
 528          * Check whether a message key has been defined currently.
 529          * @since 1.17
 530          * @return Bool: true if it is and false if not.
 531          */
 532         public function exists() {
 533                 return $this->fetchMessage() !== false;
 534         }
 535
 536         /**
 537          * Check whether a message does not exist, or is an empty string
 538          * @since 1.18
 539          * @return Bool: true if is is and false if not
 540          * @todo FIXME: Merge with isDisabled()?
 541          */
 542         public function isBlank() {
 543                 $message = $this->fetchMessage();
 544                 return $message === false || $message === '';
 545         }
 546
 547         /**
 548          * Check whether a message does not exist, is an empty string, or is "-"
 549          * @since 1.18
 550          * @return Bool: true if it is and false if not
 551          */
 552         public function isDisabled() {
 553                 $message = $this->fetchMessage();
 554                 return $message === false || $message === '' || $message === '-';
 555         }
 556
 557         /**
 558          * @since 1.17
 559          * @param $value
 560          * @return array
 561          */
 562         public static function rawParam( $value ) {
 563                 return array( 'raw' => $value );
 564         }
 565
 566         /**
 567          * @since 1.18
 568          * @param $value
 569          * @return array
 570          */
 571         public static function numParam( $value ) {
 572                 return array( 'num' => $value );
 573         }
 574
 575         /**
 576          * Substitutes any paramaters into the message text.
 577          * @since 1.17
 578          * @param $message String: the message text
 579          * @param $type String: either before or after
 580          * @return String
 581          */
 582         protected function replaceParameters( $message, $type = 'before' ) {
 583                 $replacementKeys = array();
 584                 foreach( $this->parameters as $n => $param ) {
 585                         list( $paramType, $value ) = $this->extractParam( $param );
 586                         if ( $type === $paramType ) {
 587                                 $replacementKeys['$' . ($n + 1)] = $value;
 588                         }
 589                 }
 590                 $message = strtr( $message, $replacementKeys );
 591                 return $message;
 592         }
 593
 594         /**
 595          * Extracts the parameter type and preprocessed the value if needed.
 596          * @since 1.18
 597          * @param $param String|Array: Parameter as defined in this class.
 598          * @return Tuple(type, value)
 599          * @throws MWException
 600          */
 601         protected function extractParam( $param ) {
 602                 if ( is_array( $param ) && isset( $param['raw'] ) ) {
 603                         return array( 'after', $param['raw'] );
 604                 } elseif ( is_array( $param ) && isset( $param['num'] ) ) {
 605                         // Replace number params always in before step for now.
 606                         // No support for combined raw and num params
 607                         return array( 'before', $this->language->formatNum( $param['num'] ) );
 608                 } elseif ( !is_array( $param ) ) {
 609                         return array( 'before', $param );
 610                 } else {
 611                         throw new MWException( "Invalid message parameter" );
 612                 }
 613         }
 614
 615         /**
 616          * Wrapper for what ever method we use to parse wikitext.
 617          * @since 1.17
 618          * @param $string String: Wikitext message contents
 619          * @return string Wikitext parsed into HTML
 620          */
 621         protected function parseText( $string ) {
 622                 return MessageCache::singleton()->parse( $string, $this->title, /*linestart*/true, $this->interface, $this->language )->getText();
 623         }
 624
 625         /**
 626          * Wrapper for what ever method we use to {{-transform wikitext.
 627          * @since 1.17
 628          * @param $string String: Wikitext message contents
 629          * @return string Wikitext with {{-constructs replaced with their values.
 630          */
 631         protected function transformText( $string ) {
 632                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language, $this->title );
 633         }
 634
 635         /**
 636          * Wrapper for what ever method we use to get message contents
 637          * @since 1.17
 638          * @return string
 639          */
 640         protected function fetchMessage() {
 641                 if ( !isset( $this->message ) ) {
 642                         $cache = MessageCache::singleton();
 643                         if ( is_array( $this->key ) ) {
 644                                 if ( !count( $this->key ) ) {
 645                                         throw new MWException( "Given empty message key array." );
 646                                 }
 647                                 foreach ( $this->key as $key ) {
 648                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 649                                         if ( $message !== false && $message !== '' ) {
 650                                                 break;
 651                                         }
 652                                 }
 653                                 $this->message = $message;
 654                         } else {
 655                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 656                         }
 657                 }
 658                 return $this->message;
 659         }
 660
 661 }