API: Add paging (i.e. limit and continue) parameters to prop={links,templatelinks...
[lhc/web/wiklou.git] / includes / api / ApiQueryLangLinks.php
1 <?php
2
3 /*
4 * Created on May 13, 2007
5 *
6 * API for MediaWiki 1.8+
7 *
8 * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 * http://www.gnu.org/copyleft/gpl.html
24 */
25
26 if (!defined('MEDIAWIKI')) {
27 // Eclipse helper - will be ignored in production
28 require_once ("ApiQueryBase.php");
29 }
30
31 /**
32 * A query module to list all langlinks (links to correspanding foreign language pages).
33 *
34 * @ingroup API
35 */
36 class ApiQueryLangLinks extends ApiQueryBase {
37
38 public function __construct($query, $moduleName) {
39 parent :: __construct($query, $moduleName, 'll');
40 }
41
42 public function execute() {
43 if ( $this->getPageSet()->getGoodTitleCount() == 0 )
44 return;
45
46 $params = $this->extractRequestParams();
47 $this->addFields(array (
48 'll_from',
49 'll_lang',
50 'll_title'
51 ));
52
53 $this->addTables('langlinks');
54 $this->addWhereFld('ll_from', array_keys($this->getPageSet()->getGoodTitles()));
55 if(!is_null($params['continue'])) {
56 $cont = explode('|', $params['continue']);
57 if(count($cont) != 2)
58 $this->dieUsage("Invalid continue param. You should pass the " .
59 "original value returned by the previous query", "_badcontinue");
60 $llfrom = intval($cont[0]);
61 $lllang = $this->getDb()->strencode($cont[1]);
62 $this->addWhere("ll_from > $llfrom OR ".
63 "(ll_from = $llfrom AND ".
64 "ll_lang >= '$lllang')");
65 }
66 # Don't order by ll_from if it's constant in the WHERE clause
67 if(count($this->getPageSet()->getGoodTitles()) == 1)
68 $this->addOption('ORDER BY', 'll_lang');
69 else
70 $this->addOption('ORDER BY', 'll_from, ll_lang');
71 $this->addOption('LIMIT', $params['limit'] + 1);
72 $res = $this->select(__METHOD__);
73
74 $data = array();
75 $lastId = 0; // database has no ID 0
76 $count = 0;
77 $db = $this->getDB();
78 while ($row = $db->fetchObject($res)) {
79 if (++$count > $params['limit']) {
80 // We've reached the one extra which shows that
81 // there are additional pages to be had. Stop here...
82 $this->setContinueEnumParameter('continue', "{$row->ll_from}|{$row->ll_lang}");
83 break;
84 }
85 if ($lastId != $row->ll_from) {
86 if($lastId != 0) {
87 $this->addPageSubItems($lastId, $data);
88 $data = array();
89 }
90 $lastId = $row->ll_from;
91 }
92
93 $entry = array('lang' => $row->ll_lang);
94 ApiResult :: setContent($entry, $row->ll_title);
95 $data[] = $entry;
96 }
97
98 if($lastId != 0) {
99 $this->addPageSubItems($lastId, $data);
100 }
101
102 $db->freeResult($res);
103 }
104
105 public function getAllowedParams() {
106 return array(
107 'limit' => array(
108 ApiBase :: PARAM_DFLT => 10,
109 ApiBase :: PARAM_TYPE => 'limit',
110 ApiBase :: PARAM_MIN => 1,
111 ApiBase :: PARAM_MAX => ApiBase :: LIMIT_BIG1,
112 ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
113 ),
114 'continue' => null,
115 );
116 }
117
118 public function getParamDescription () {
119 return array(
120 'limit' => 'How many langlinks to return',
121 'continue' => 'When more results are available, use this to continue',
122 );
123 }
124
125 public function getDescription() {
126 return 'Returns all interlanguage links from the given page(s)';
127 }
128
129 protected function getExamples() {
130 return array (
131 "Get interlanguage links from the [[Main Page]]:",
132 " api.php?action=query&prop=langlinks&titles=Main%20Page&redirects",
133 );
134 }
135
136 public function getVersion() {
137 return __CLASS__ . ': $Id$';
138 }
139 }