includes/Message.php

   1 <?php
   2 /**
   3  * This class provides methods for fetching interface messages and
   4  * processing them into variety of formats that are needed in MediaWiki.
   5  *
   6  * It is intented to replace the old wfMsg* functions that over time grew
   7  * unusable.
   8  * @see https://www.mediawiki.org/wiki/New_messages_API for
   9  * equivalence between old and new functions.
  10  *
  11  * Below, you will find several examples of wfMessage() usage.
  12  *
  13  *
  14  * Fetching a message text for interface message
  15  * @code
  16  *    $button = Xml::button( wfMessage( 'submit' )->text() );
  17  * @endcode
  18  *
  19  * Messages can have parameters:
  20  *
  21  * @code
  22  *    wfMessage( 'welcome-to' )->params( $wgSitename )->text();
  23  * @endcode
  24  *
  25  * {{GRAMMAR}} and friends work correctly
  26  * @code
  27  *    wfMessage( 'are-friends', $user, $friend );
  28  *    wfMessage( 'bad-message' )->rawParams( '<script>...</script>' )->escaped();
  29  * @endcode
  30  *
  31  * Sometimes the message text ends up in the database, so content language is needed.
  32  * @code
  33  *    wfMessage( 'file-log', $user, $filename )->inContentLanguage()->text()
  34  * </pre>
  35  * @endcode
  36  *
  37  * Checking whether a message exists:
  38  * @code
  39  *    wfMessage( 'mysterious-message' )->exists()
  40  * @endcode
  41  *
  42  * If you want to use a different language:
  43  * @code
  44  *    wfMessage( 'email-header' )->inLanguage( $user->getOption( 'language' ) )->plain()
  45  * @endcode
  46  *
  47  * @note You cannot parse the text except in the content or interface
  48  * @note languages
  49  *
  50  * Comparison with old wfMsg* functions:
  51  *
  52  * Use full parsing.
  53  *
  54  * @code
  55  *     wfMsgExt( 'key', array( 'parseinline' ), 'apple' );
  56  *     === wfMessage( 'key', 'apple' )->parse();
  57  * @endcode
  58  *
  59  * Parseinline is used because it is more useful when pre-building html.
  60  * In normal use it is better to use OutputPage::(add|wrap)WikiMsg.
  61  *
  62  * Places where html cannot be used. {{-transformation is done.
  63  * @code
  64  *     wfMsgExt( 'key', array( 'parsemag' ), 'apple', 'pear' );
  65  *     === wfMessage( 'key', 'apple', 'pear' )->text();
  66  * @endcode
  67  *
  68  * Shortcut for escaping the message too, similar to wfMsgHTML, but
  69  * parameters are not replaced after escaping by default.
  70  * @code
  71  * $escaped = wfMessage( 'key' )->rawParams( 'apple' )->escaped();
  72  * @endcode
  73  *
  74  * @todo
  75  * - test, can we have tests?
  76  *
  77  * @see https://www.mediawiki.org/wiki/WfMessage()
  78  * @see https://www.mediawiki.org/wiki/New_messages_API
  79  * @see https://www.mediawiki.org/wiki/Localisation
  80  *
  81  * @since 1.17
  82  * @author Niklas Laxström
  83  */
  84 class Message {
  85         /**
  86          * In which language to get this message. True, which is the default,
  87          * means the current interface language, false content language.
  88          */
  89         protected $interface = true;
  90
  91         /**
  92          * In which language to get this message. Overrides the $interface
  93          * variable.
  94          *
  95          * @var Language
  96          */
  97         protected $language = null;
  98
  99         /**
 100          * The message key.
 101          */
 102         protected $key;
 103
 104         /**
 105          * List of parameters which will be substituted into the message.
 106          */
 107         protected $parameters = array();
 108
 109         /**
 110          * Format for the message.
 111          * Supported formats are:
 112          * * text (transform)
 113          * * escaped (transform+htmlspecialchars)
 114          * * block-parse
 115          * * parse (default)
 116          * * plain
 117          */
 118         protected $format = 'parse';
 119
 120         /**
 121          * Whether database can be used.
 122          */
 123         protected $useDatabase = true;
 124
 125         /**
 126          * Title object to use as context
 127          */
 128         protected $title = null;
 129
 130         /**
 131          * @var string
 132          */
 133         protected $message;
 134
 135         /**
 136          * Constructor.
 137          * @param $key: message key, or array of message keys to try and use the first non-empty message for
 138          * @param $params Array message parameters
 139          * @return Message: $this
 140          */
 141         public function __construct( $key, $params = array() ) {
 142                 global $wgLang;
 143                 $this->key = $key;
 144                 $this->parameters = array_values( $params );
 145                 $this->language = $wgLang;
 146         }
 147
 148         /**
 149          * Factory function that is just wrapper for the real constructor. It is
 150          * intented to be used instead of the real constructor, because it allows
 151          * chaining method calls, while new objects don't.
 152          * @param $key String: message key
 153          * @param Varargs: parameters as Strings
 154          * @return Message: $this
 155          */
 156         public static function newFromKey( $key /*...*/ ) {
 157                 $params = func_get_args();
 158                 array_shift( $params );
 159                 return new self( $key, $params );
 160         }
 161
 162         /**
 163          * Factory function accepting multiple message keys and returning a message instance
 164          * for the first message which is non-empty. If all messages are empty then an
 165          * instance of the first message key is returned.
 166          * @param Varargs: message keys (or first arg as an array of all the message keys)
 167          * @return Message: $this
 168          */
 169         public static function newFallbackSequence( /*...*/ ) {
 170                 $keys = func_get_args();
 171                 if ( func_num_args() == 1 ) {
 172                         if ( is_array($keys[0]) ) {
 173                                 // Allow an array to be passed as the first argument instead
 174                                 $keys = array_values($keys[0]);
 175                         } else {
 176                                 // Optimize a single string to not need special fallback handling
 177                                 $keys = $keys[0];
 178                         }
 179                 }
 180                 return new self( $keys );
 181         }
 182
 183         /**
 184          * Adds parameters to the parameter list of this message.
 185          * @param Varargs: parameters as Strings, or a single argument that is an array of Strings
 186          * @return Message: $this
 187          */
 188         public function params( /*...*/ ) {
 189                 $args = func_get_args();
 190                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 191                         $args = $args[0];
 192                 }
 193                 $args_values = array_values( $args );
 194                 $this->parameters = array_merge( $this->parameters, $args_values );
 195                 return $this;
 196         }
 197
 198         /**
 199          * Add parameters that are substituted after parsing or escaping.
 200          * In other words the parsing process cannot access the contents
 201          * of this type of parameter, and you need to make sure it is
 202          * sanitized beforehand.  The parser will see "$n", instead.
 203          * @param Varargs: raw parameters as Strings (or single argument that is an array of raw parameters)
 204          * @return Message: $this
 205          */
 206         public function rawParams( /*...*/ ) {
 207                 $params = func_get_args();
 208                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 209                         $params = $params[0];
 210                 }
 211                 foreach( $params as $param ) {
 212                         $this->parameters[] = self::rawParam( $param );
 213                 }
 214                 return $this;
 215         }
 216
 217         /**
 218          * Add parameters that are numeric and will be passed through
 219          * Language::formatNum before substitution
 220          * @param Varargs: numeric parameters (or single argument that is array of numeric parameters)
 221          * @return Message: $this
 222          */
 223         public function numParams( /*...*/ ) {
 224                 $params = func_get_args();
 225                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 226                         $params = $params[0];
 227                 }
 228                 foreach( $params as $param ) {
 229                         $this->parameters[] = self::numParam( $param );
 230                 }
 231                 return $this;
 232         }
 233
 234         /**
 235          * Set the language and the title from a context object
 236          *
 237          * @param $context IContextSource
 238          * @return Message: $this
 239          */
 240         public function setContext( IContextSource $context ) {
 241                 $this->inLanguage( $context->getLanguage() );
 242                 $this->title( $context->getTitle() );
 243
 244                 return $this;
 245         }
 246
 247         /**
 248          * Request the message in any language that is supported.
 249          * As a side effect interface message status is unconditionally
 250          * turned off.
 251          * @param $lang Mixed: language code or Language object.
 252          * @return Message: $this
 253          */
 254         public function inLanguage( $lang ) {
 255                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 256                         $this->language = $lang;
 257                 } elseif ( is_string( $lang ) ) {
 258                         if( $this->language->getCode() != $lang ) {
 259                                 $this->language = Language::factory( $lang );
 260                         }
 261                 } else {
 262                         $type = gettype( $lang );
 263                         throw new MWException( __METHOD__ . " must be "
 264                                 . "passed a String or Language object; $type given"
 265                         );
 266                 }
 267                 $this->interface = false;
 268                 return $this;
 269         }
 270
 271         /**
 272          * Request the message in the wiki's content language,
 273          * unless it is disabled for this message.
 274          * @see $wgForceUIMsgAsContentMsg
 275          * @return Message: $this
 276          */
 277         public function inContentLanguage() {
 278                 global $wgForceUIMsgAsContentMsg;
 279                 if ( in_array( $this->key, (array)$wgForceUIMsgAsContentMsg ) ) {
 280                         return $this;
 281                 }
 282
 283                 global $wgContLang;
 284                 $this->interface = false;
 285                 $this->language = $wgContLang;
 286                 return $this;
 287         }
 288
 289         /**
 290          * Enable or disable database use.
 291          * @param $value Boolean
 292          * @return Message: $this
 293          */
 294         public function useDatabase( $value ) {
 295                 $this->useDatabase = (bool) $value;
 296                 return $this;
 297         }
 298
 299         /**
 300          * Set the Title object to use as context when transforming the message
 301          *
 302          * @param $title Title object
 303          * @return Message: $this
 304          */
 305         public function title( $title ) {
 306                 $this->title = $title;
 307                 return $this;
 308         }
 309
 310         /**
 311          * Returns the message parsed from wikitext to HTML.
 312          * @return String: HTML
 313          */
 314         public function toString() {
 315                 $string = $this->getMessageText();
 316
 317                 # Replace parameters before text parsing
 318                 $string = $this->replaceParameters( $string, 'before' );
 319
 320                 # Maybe transform using the full parser
 321                 if( $this->format === 'parse' ) {
 322                         $string = $this->parseText( $string );
 323                         $m = array();
 324                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 325                                 $string = $m[1];
 326                         }
 327                 } elseif( $this->format === 'block-parse' ){
 328                         $string = $this->parseText( $string );
 329                 } elseif( $this->format === 'text' ){
 330                         $string = $this->transformText( $string );
 331                 } elseif( $this->format === 'escaped' ){
 332                         $string = $this->transformText( $string );
 333                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 334                 }
 335
 336                 # Raw parameter replacement
 337                 $string = $this->replaceParameters( $string, 'after' );
 338
 339                 return $string;
 340         }
 341
 342         /**
 343          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 344          *     $foo = Message::get($key);
 345          *     $string = "<abbr>$foo</abbr>";
 346          * @return String
 347          */
 348         public function __toString() {
 349                 return $this->toString();
 350         }
 351
 352         /**
 353          * Fully parse the text from wikitext to HTML
 354          * @return String parsed HTML
 355          */
 356         public function parse() {
 357                 $this->format = 'parse';
 358                 return $this->toString();
 359         }
 360
 361         /**
 362          * Returns the message text. {{-transformation is done.
 363          * @return String: Unescaped message text.
 364          */
 365         public function text() {
 366                 $this->format = 'text';
 367                 return $this->toString();
 368         }
 369
 370         /**
 371          * Returns the message text as-is, only parameters are subsituted.
 372          * @return String: Unescaped untransformed message text.
 373          */
 374         public function plain() {
 375                 $this->format = 'plain';
 376                 return $this->toString();
 377         }
 378
 379         /**
 380          * Returns the parsed message text which is always surrounded by a block element.
 381          * @return String: HTML
 382          */
 383         public function parseAsBlock() {
 384                 $this->format = 'block-parse';
 385                 return $this->toString();
 386         }
 387
 388         /**
 389          * Returns the message text. {{-transformation is done and the result
 390          * is escaped excluding any raw parameters.
 391          * @return String: Escaped message text.
 392          */
 393         public function escaped() {
 394                 $this->format = 'escaped';
 395                 return $this->toString();
 396         }
 397
 398         /**
 399          * Check whether a message key has been defined currently.
 400          * @return Bool: true if it is and false if not.
 401          */
 402         public function exists() {
 403                 return $this->fetchMessage() !== false;
 404         }
 405
 406         /**
 407          * Check whether a message does not exist, or is an empty string
 408          * @return Bool: true if is is and false if not
 409          * @todo FIXME: Merge with isDisabled()?
 410          */
 411         public function isBlank() {
 412                 $message = $this->fetchMessage();
 413                 return $message === false || $message === '';
 414         }
 415
 416         /**
 417          * Check whether a message does not exist, is an empty string, or is "-"
 418          * @return Bool: true if is is and false if not
 419          */
 420         public function isDisabled() {
 421                 $message = $this->fetchMessage();
 422                 return $message === false || $message === '' || $message === '-';
 423         }
 424
 425         /**
 426          * @param $value
 427          * @return array
 428          */
 429         public static function rawParam( $value ) {
 430                 return array( 'raw' => $value );
 431         }
 432
 433         /**
 434          * @param $value
 435          * @return array
 436          */
 437         public static function numParam( $value ) {
 438                 return array( 'num' => $value );
 439         }
 440
 441         /**
 442          * Substitutes any paramaters into the message text.
 443          * @param $message String: the message text
 444          * @param $type String: either before or after
 445          * @return String
 446          */
 447         protected function replaceParameters( $message, $type = 'before' ) {
 448                 $replacementKeys = array();
 449                 foreach( $this->parameters as $n => $param ) {
 450                         list( $paramType, $value ) = $this->extractParam( $param );
 451                         if ( $type === $paramType ) {
 452                                 $replacementKeys['$' . ($n + 1)] = $value;
 453                         }
 454                 }
 455                 $message = strtr( $message, $replacementKeys );
 456                 return $message;
 457         }
 458
 459         /**
 460          * Extracts the parameter type and preprocessed the value if needed.
 461          * @param $param String|Array: Parameter as defined in this class.
 462          * @return Tuple(type, value)
 463          * @throws MWException
 464          */
 465         protected function extractParam( $param ) {
 466                 if ( is_array( $param ) && isset( $param['raw'] ) ) {
 467                         return array( 'after', $param['raw'] );
 468                 } elseif ( is_array( $param ) && isset( $param['num'] ) ) {
 469                         // Replace number params always in before step for now.
 470                         // No support for combined raw and num params
 471                         return array( 'before', $this->language->formatNum( $param['num'] ) );
 472                 } elseif ( !is_array( $param ) ) {
 473                         return array( 'before', $param );
 474                 } else {
 475                         throw new MWException( "Invalid message parameter" );
 476                 }
 477         }
 478
 479         /**
 480          * Wrapper for what ever method we use to parse wikitext.
 481          * @param $string String: Wikitext message contents
 482          * @return string Wikitext parsed into HTML
 483          */
 484         protected function parseText( $string ) {
 485                 return MessageCache::singleton()->parse( $string, $this->title, /*linestart*/true, $this->interface, $this->language )->getText();
 486         }
 487
 488         /**
 489          * Wrapper for what ever method we use to {{-transform wikitext.
 490          * @param $string String: Wikitext message contents
 491          * @return string Wikitext with {{-constructs replaced with their values.
 492          */
 493         protected function transformText( $string ) {
 494                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language, $this->title );
 495         }
 496
 497         /**
 498          * Returns the textual value for the message.
 499          * @return Message contents or placeholder
 500          */
 501         protected function getMessageText() {
 502                 $message = $this->fetchMessage();
 503                 if ( $message === false ) {
 504                         return '&lt;' . htmlspecialchars( is_array($this->key) ? $this->key[0] : $this->key ) . '&gt;';
 505                 } else {
 506                         return $message;
 507                 }
 508         }
 509
 510         /**
 511          * Wrapper for what ever method we use to get message contents
 512          *
 513          * @return string
 514          */
 515         protected function fetchMessage() {
 516                 if ( !isset( $this->message ) ) {
 517                         $cache = MessageCache::singleton();
 518                         if ( is_array($this->key) ) {
 519                                 foreach ( $this->key as $key ) {
 520                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 521                                         if ( $message !== false && $message !== '' ) {
 522                                                 break;
 523                                         }
 524                                 }
 525                                 $this->message = $message;
 526                         } else {
 527                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 528                         }
 529                 }
 530                 return $this->message;
 531         }
 532
 533 }