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