includes/title/TitleValue.php

   1 <?php
   2 /**
   3  * Representation of a page title within MediaWiki.
   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 Daniel Kinzler
  22  */
  23 use MediaWiki\Linker\LinkTarget;
  24 use Wikimedia\Assert\Assert;
  25 use Wikimedia\Assert\ParameterTypeException;
  26
  27 /**
  28  * Represents a page (or page fragment) title within MediaWiki.
  29  *
  30  * @note In contrast to Title, this is designed to be a plain value object. That is,
  31  * it is immutable, does not use global state, and causes no side effects.
  32  *
  33  * @see https://www.mediawiki.org/wiki/Requests_for_comment/TitleValue
  34  * @since 1.23
  35  */
  36 class TitleValue implements LinkTarget {
  37
  38         /**
  39          * @deprecated in 1.31. This class is immutable. Use the getter for access.
  40          * @var int
  41          */
  42         protected $namespace;
  43
  44         /**
  45          * @deprecated in 1.31. This class is immutable. Use the getter for access.
  46          * @var string
  47          */
  48         protected $dbkey;
  49
  50         /**
  51          * @deprecated in 1.31. This class is immutable. Use the getter for access.
  52          * @var string
  53          */
  54         protected $fragment;
  55
  56         /**
  57          * @deprecated in 1.31. This class is immutable. Use the getter for access.
  58          * @var string
  59          */
  60         protected $interwiki;
  61
  62         /**
  63          * Text form including namespace/interwiki, initialised on demand
  64          *
  65          * Only public to share cache with TitleFormatter
  66          *
  67          * @private
  68          * @var string
  69          */
  70         public $prefixedText = null;
  71
  72         /**
  73          * Constructs a TitleValue.
  74          *
  75          * @note TitleValue expects a valid DB key; typically, a TitleValue is constructed either
  76          * from a database entry, or by a TitleParser. We could apply "some" normalization here,
  77          * such as substituting spaces by underscores, but that would encourage the use of
  78          * un-normalized text when constructing TitleValues. For constructing a TitleValue from
  79          * user input or external sources, use a TitleParser.
  80          *
  81          * @param int $namespace The namespace ID. This is not validated.
  82          * @param string $dbkey The page title in valid DBkey form. No normalization is applied.
  83          * @param string $fragment The fragment title. Use '' to represent the whole page.
  84          *   No validation or normalization is applied.
  85          * @param string $interwiki The interwiki component
  86          *
  87          * @throws InvalidArgumentException
  88          */
  89         public function __construct( $namespace, $dbkey, $fragment = '', $interwiki = '' ) {
  90                 if ( !is_int( $namespace ) ) {
  91                         throw new ParameterTypeException( '$namespace', 'int' );
  92                 }
  93                 if ( !is_string( $dbkey ) ) {
  94                         throw new ParameterTypeException( '$dbkey', 'string' );
  95                 }
  96                 if ( !is_string( $fragment ) ) {
  97                         throw new ParameterTypeException( '$fragment', 'string' );
  98                 }
  99                 if ( !is_string( $interwiki ) ) {
 100                         throw new ParameterTypeException( '$interwiki', 'string' );
 101                 }
 102
 103                 // Sanity check, no full validation or normalization applied here!
 104                 Assert::parameter( !preg_match( '/^_|[ \r\n\t]|_$/', $dbkey ), '$dbkey',
 105                         "invalid DB key '$dbkey'" );
 106                 Assert::parameter( $dbkey !== '' || ( $fragment !== '' && $namespace === NS_MAIN ),
 107                         '$dbkey', 'should not be empty unless namespace is main and fragment is non-empty' );
 108
 109                 $this->namespace = $namespace;
 110                 $this->dbkey = $dbkey;
 111                 $this->fragment = $fragment;
 112                 $this->interwiki = $interwiki;
 113         }
 114
 115         /**
 116          * @since 1.23
 117          * @return int
 118          */
 119         public function getNamespace() {
 120                 return $this->namespace;
 121         }
 122
 123         /**
 124          * @since 1.27
 125          * @param int $ns
 126          * @return bool
 127          */
 128         public function inNamespace( $ns ) {
 129                 return $this->namespace == $ns;
 130         }
 131
 132         /**
 133          * @since 1.23
 134          * @return string
 135          */
 136         public function getFragment() {
 137                 return $this->fragment;
 138         }
 139
 140         /**
 141          * @since 1.27
 142          * @return bool
 143          */
 144         public function hasFragment() {
 145                 return $this->fragment !== '';
 146         }
 147
 148         /**
 149          * Returns the title's DB key, as supplied to the constructor,
 150          * without namespace prefix or fragment.
 151          * @since 1.23
 152          *
 153          * @return string
 154          */
 155         public function getDBkey() {
 156                 return $this->dbkey;
 157         }
 158
 159         /**
 160          * Returns the title in text form,
 161          * without namespace prefix or fragment.
 162          * @since 1.23
 163          *
 164          * This is computed from the DB key by replacing any underscores with spaces.
 165          *
 166          * @note To get a title string that includes the namespace and/or fragment,
 167          *       use a TitleFormatter.
 168          *
 169          * @return string
 170          */
 171         public function getText() {
 172                 return str_replace( '_', ' ', $this->dbkey );
 173         }
 174
 175         /**
 176          * Creates a new TitleValue for a different fragment of the same page.
 177          *
 178          * @since 1.27
 179          * @param string $fragment The fragment name, or "" for the entire page.
 180          *
 181          * @return TitleValue
 182          */
 183         public function createFragmentTarget( $fragment ) {
 184                 return new TitleValue(
 185                         $this->namespace,
 186                         $this->dbkey,
 187                         $fragment,
 188                         $this->interwiki
 189                 );
 190         }
 191
 192         /**
 193          * Whether it has an interwiki part
 194          *
 195          * @since 1.27
 196          * @return bool
 197          */
 198         public function isExternal() {
 199                 return $this->interwiki !== '';
 200         }
 201
 202         /**
 203          * Returns the interwiki part
 204          *
 205          * @since 1.27
 206          * @return string
 207          */
 208         public function getInterwiki() {
 209                 return $this->interwiki;
 210         }
 211
 212         /**
 213          * Returns a string representation of the title, for logging. This is purely informative
 214          * and must not be used programmatically. Use the appropriate TitleFormatter to generate
 215          * the correct string representation for a given use.
 216          * @since 1.23
 217          *
 218          * @return string
 219          */
 220         public function __toString() {
 221                 $name = $this->namespace . ':' . $this->dbkey;
 222
 223                 if ( $this->fragment !== '' ) {
 224                         $name .= '#' . $this->fragment;
 225                 }
 226
 227                 if ( $this->interwiki !== '' ) {
 228                         $name = $this->interwiki . ':' . $name;
 229                 }
 230
 231                 return $name;
 232         }
 233 }