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 use MediaWiki\Linker\LinkTarget;
  25 use Wikimedia\Assert\Assert;
  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          * @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          * @var string
  54          */
  55         protected $interwiki;
  56
  57         /**
  58          * Constructs a TitleValue.
  59          *
  60          * @note TitleValue expects a valid DB key; typically, a TitleValue is constructed either
  61          * from a database entry, or by a TitleParser. We could apply "some" normalization here,
  62          * such as substituting spaces by underscores, but that would encourage the use of
  63          * un-normalized text when constructing TitleValues. For constructing a TitleValue from
  64          * user input or external sources, use a TitleParser.
  65          *
  66          * @param int $namespace The namespace ID. This is not validated.
  67          * @param string $dbkey The page title in valid DBkey form. No normalization is applied.
  68          * @param string $fragment The fragment title. Use '' to represent the whole page.
  69          *   No validation or normalization is applied.
  70          * @param string $interwiki The interwiki component
  71          *
  72          * @throws InvalidArgumentException
  73          */
  74         public function __construct( $namespace, $dbkey, $fragment = '', $interwiki = '' ) {
  75                 Assert::parameterType( 'integer', $namespace, '$namespace' );
  76                 Assert::parameterType( 'string', $dbkey, '$dbkey' );
  77                 Assert::parameterType( 'string', $fragment, '$fragment' );
  78                 Assert::parameterType( 'string', $interwiki, '$interwiki' );
  79
  80                 // Sanity check, no full validation or normalization applied here!
  81                 Assert::parameter( !preg_match( '/^_|[ \r\n\t]|_$/', $dbkey ), '$dbkey', 'invalid DB key' );
  82                 Assert::parameter( $dbkey !== '', '$dbkey', 'should not be empty' );
  83
  84                 $this->namespace = $namespace;
  85                 $this->dbkey = $dbkey;
  86                 $this->fragment = $fragment;
  87                 $this->interwiki = $interwiki;
  88         }
  89
  90         /**
  91          * @return int
  92          */
  93         public function getNamespace() {
  94                 return $this->namespace;
  95         }
  96
  97         /**
  98          * @return string
  99          */
 100         public function getFragment() {
 101                 return $this->fragment;
 102         }
 103
 104         /**
 105          * @since 1.27
 106          * @return bool
 107          */
 108         public function hasFragment() {
 109                 return $this->fragment !== '';
 110         }
 111
 112         /**
 113          * Returns the title's DB key, as supplied to the constructor,
 114          * without namespace prefix or fragment.
 115          *
 116          * @return string
 117          */
 118         public function getDBkey() {
 119                 return $this->dbkey;
 120         }
 121
 122         /**
 123          * Returns the title in text form,
 124          * without namespace prefix or fragment.
 125          *
 126          * This is computed from the DB key by replacing any underscores with spaces.
 127          *
 128          * @note To get a title string that includes the namespace and/or fragment,
 129          *       use a TitleFormatter.
 130          *
 131          * @return string
 132          */
 133         public function getText() {
 134                 return str_replace( '_', ' ', $this->getDBkey() );
 135         }
 136
 137         /**
 138          * Creates a new TitleValue for a different fragment of the same page.
 139          *
 140          * @since 1.27
 141          * @param string $fragment The fragment name, or "" for the entire page.
 142          *
 143          * @return TitleValue
 144          */
 145         public function createFragmentTarget( $fragment ) {
 146                 return new TitleValue(
 147                         $this->namespace,
 148                         $this->dbkey,
 149                         $fragment,
 150                         $this->interwiki
 151                 );
 152         }
 153
 154         /**
 155          * Whether it has an interwiki part
 156          *
 157          * @since 1.27
 158          * @return bool
 159          */
 160         public function isExternal() {
 161                 return $this->interwiki !== '';
 162         }
 163
 164         /**
 165          * Returns the interwiki part
 166          *
 167          * @since 1.27
 168          * @return string
 169          */
 170         public function getInterwiki() {
 171                 return $this->interwiki;
 172         }
 173
 174         /**
 175          * Returns a string representation of the title, for logging. This is purely informative
 176          * and must not be used programmatically. Use the appropriate TitleFormatter to generate
 177          * the correct string representation for a given use.
 178          *
 179          * @return string
 180          */
 181         public function __toString() {
 182                 $name = $this->namespace . ':' . $this->dbkey;
 183
 184                 if ( $this->fragment !== '' ) {
 185                         $name .= '#' . $this->fragment;
 186                 }
 187
 188                 if ( $this->interwiki !== '' ) {
 189                         $name = $this->interwiki . ':' . $name;
 190                 }
 191
 192                 return $name;
 193         }
 194 }