1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
|
<?php
/**
* Implements Special:Randompage
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup SpecialPage
* @author Rob Church <robchur@gmail.com>, Ilmari Karonen
*/
/**
* Special page to direct the user to a random page
*
* @ingroup SpecialPage
*/
class RandomPage extends SpecialPage {
private $namespaces; // namespaces to select pages from
protected $isRedir = false; // should the result be a redirect?
protected $extra = array(); // Extra SQL statements
public function __construct( $name = 'Randompage' ){
$this->namespaces = MWNamespace::getContentNamespaces();
parent::__construct( $name );
}
public function getNamespaces() {
return $this->namespaces;
}
public function setNamespace ( $ns ) {
if( !$ns || $ns < NS_MAIN ) {
$ns = NS_MAIN;
}
$this->namespaces = array( $ns );
}
// select redirects instead of normal pages?
public function isRedirect(){
return $this->isRedir;
}
public function execute( $par ) {
global $wgContLang;
if ( $par ) {
$this->setNamespace( $wgContLang->getNsIndex( $par ) );
}
$title = $this->getRandomTitle();
if( is_null( $title ) ) {
$this->setHeaders();
$this->getOutput()->addWikiMsg( strtolower( $this->getName() ) . '-nopages',
$this->getNsList(), count( $this->namespaces ) );
return;
}
$redirectParam = $this->isRedirect() ? array( 'redirect' => 'no' ) : array();
$query = array_merge( $this->getRequest()->getValues(), $redirectParam );
unset( $query['title'] );
$this->getOutput()->redirect( $title->getFullUrl( $query ) );
}
/**
* Get a comma-delimited list of namespaces we don't have
* any pages in
* @return String
*/
private function getNsList() {
global $wgContLang;
$nsNames = array();
foreach( $this->namespaces as $n ) {
if( $n === NS_MAIN ) {
$nsNames[] = wfMsgNoTrans( 'blanknamespace' );
} else {
$nsNames[] = $wgContLang->getNsText( $n );
}
}
return $wgContLang->commaList( $nsNames );
}
/**
* Choose a random title.
* @return Title object (or null if nothing to choose from)
*/
public function getRandomTitle() {
$randstr = wfRandom();
$title = null;
if ( !wfRunHooks( 'SpecialRandomGetRandomTitle', array( &$randstr, &$this->isRedir, &$this->namespaces,
&$this->extra, &$title ) ) ) {
return $title;
}
$row = $this->selectRandomPageFromDB( $randstr );
/* If we picked a value that was higher than any in
* the DB, wrap around and select the page with the
* lowest value instead! One might think this would
* skew the distribution, but in fact it won't cause
* any more bias than what the page_random scheme
* causes anyway. Trust me, I'm a mathematician. :)
*/
if( !$row ) {
$row = $this->selectRandomPageFromDB( "0" );
}
if( $row ) {
return Title::makeTitleSafe( $row->page_namespace, $row->page_title );
} else {
return null;
}
}
protected function getQueryInfo( $randstr ) {
$redirect = $this->isRedirect() ? 1 : 0;
return array(
'tables' => array( 'page' ),
'fields' => array( 'page_title', 'page_namespace' ),
'conds' => array_merge( array(
'page_namespace' => $this->namespaces,
'page_is_redirect' => $redirect,
'page_random >= ' . $randstr
), $this->extra ),
'options' => array(
'ORDER BY' => 'page_random',
'USE INDEX' => 'page_random',
'LIMIT' => 1,
),
'join_conds' => array()
);
}
private function selectRandomPageFromDB( $randstr, $fname = __METHOD__ ) {
$dbr = wfGetDB( DB_SLAVE );
$query = $this->getQueryInfo( $randstr );
$res = $dbr->select(
$query['tables'],
$query['fields'],
$query['conds'],
$fname,
$query['options'],
$query['join_conds']
);
return $dbr->fetchObject( $res );
}
}
|
