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  * @license GPL 2+
  22  * @author Daniel Kinzler
  23  */
  24
  25 /**
  26  * Represents a page (or page fragment) title within %MediaWiki.
  27  *
  28  * @note In contrast to Title, this is designed to be a plain value object. That is,
  29  * it is immutable, does not use global state, and causes no side effects.
  30  *
  31  * @note TitleValue represents the title of a local page (or fragment of a page).
  32  * It does not represent a link, and does not support interwiki prefixes etc.
  33  *
  34  * @see https://www.mediawiki.org/wiki/Requests_for_comment/TitleValue
  35  */
  36 class TitleValue {
  37         /**
  38          * @var int
  39          */
  40         protected $namespace;
  41
  42         /**
  43          * @var string
  44          */
  45         protected $dbkey;
  46
  47         /**
  48          * @var string
  49          */
  50         protected $fragment;
  51
  52         /**
  53          * Constructs a TitleValue.
  54          *
  55          * @note TitleValue expects a valid DB key; typically, a TitleValue is constructed either
  56          * from a database entry, or by a TitleParser. We could apply "some" normalization here,
  57          * such as substituting spaces by underscores, but that would encourage the use of
  58          * un-normalized text when constructing TitleValues. For constructing a TitleValue from
  59          * user input or external sources, use a TitleParser.
  60          *
  61          * @param int $namespace The namespace ID. This is not validated.
  62          * @param string $dbkey The page title in valid DBkey form. No normalization is applied.
  63          * @param string $fragment The fragment title. Use '' to represent the whole page.
  64          *   No validation or normalization is applied.
  65          *
  66          * @throws InvalidArgumentException
  67          */
  68         public function __construct( $namespace, $dbkey, $fragment = '' ) {
  69                 if ( !is_int( $namespace ) ) {
  70                         throw new InvalidArgumentException( '$namespace must be an integer' );
  71                 }
  72
  73                 if ( !is_string( $dbkey ) ) {
  74                         throw new InvalidArgumentException( '$dbkey must be a string' );
  75                 }
  76
  77                 // Sanity check, no full validation or normalization applied here!
  78                 if ( preg_match( '/^_|[ \r\n\t]|_$/', $dbkey ) ) {
  79                         throw new InvalidArgumentException( '$dbkey must be a valid DB key: ' . $dbkey );
  80                 }
  81
  82                 if ( !is_string( $fragment ) ) {
  83                         throw new InvalidArgumentException( '$fragment must be a string' );
  84                 }
  85
  86                 if ( $dbkey === '' ) {
  87                         throw new InvalidArgumentException( '$dbkey must not be empty' );
  88                 }
  89
  90                 $this->namespace = $namespace;
  91                 $this->dbkey = $dbkey;
  92                 $this->fragment = $fragment;
  93         }
  94
  95         /**
  96          * @return int
  97          */
  98         public function getNamespace() {
  99                 return $this->namespace;
 100         }
 101
 102         /**
 103          * @return string
 104          */
 105         public function getFragment() {
 106                 return $this->fragment;
 107         }
 108
 109         /**
 110          * Returns the title's DB key, as supplied to the constructor,
 111          * without namespace prefix or fragment.
 112          *
 113          * @return string
 114          */
 115         public function getDBkey() {
 116                 return $this->dbkey;
 117         }
 118
 119         /**
 120          * Returns the title in text form,
 121          * without namespace prefix or fragment.
 122          *
 123          * This is computed from the DB key by replacing any underscores with spaces.
 124          *
 125          * @note To get a title string that includes the namespace and/or fragment,
 126          *       use a TitleFormatter.
 127          *
 128          * @return string
 129          */
 130         public function getText() {
 131                 return str_replace( '_', ' ', $this->getDBkey() );
 132         }
 133
 134         /**
 135          * Creates a new TitleValue for a different fragment of the same page.
 136          *
 137          * @param string $fragment The fragment name, or "" for the entire page.
 138          *
 139          * @return TitleValue
 140          */
 141         public function createFragmentTitle( $fragment ) {
 142                 return new TitleValue( $this->namespace, $this->dbkey, $fragment );
 143         }
 144
 145         /**
 146          * Returns a string representation of the title, for logging. This is purely informative
 147          * and must not be used programmatically. Use the appropriate TitleFormatter to generate
 148          * the correct string representation for a given use.
 149          *
 150          * @return string
 151          */
 152         public function __toString() {
 153                 $name = $this->namespace . ':' . $this->dbkey;
 154
 155                 if ( $this->fragment !== '' ) {
 156                         $name .= '#' . $this->fragment;
 157                 }
 158
 159                 return $name;
 160         }
 161 }