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