API: Add paging (i.e. limit and continue) parameters to prop={links,templatelinks...
[lhc/web/wiklou.git] / includes / api / ApiQueryCategories.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 enumerate categories the set of pages belong to.
33 *
34 * @ingroup API
35 */
36 class ApiQueryCategories extends ApiQueryGeneratorBase {
37
38 public function __construct($query, $moduleName) {
39 parent :: __construct($query, $moduleName, 'cl');
40 }
41
42 public function execute() {
43 $this->run();
44 }
45
46 public function executeGenerator($resultPageSet) {
47 $this->run($resultPageSet);
48 }
49
50 private function run($resultPageSet = null) {
51
52 if ($this->getPageSet()->getGoodTitleCount() == 0)
53 return; // nothing to do
54
55 $params = $this->extractRequestParams();
56 $prop = $params['prop'];
57
58 $this->addFields(array (
59 'cl_from',
60 'cl_to'
61 ));
62
63 $fld_sortkey = $fld_timestamp = false;
64 if (!is_null($prop)) {
65 foreach($prop as $p) {
66 switch ($p) {
67 case 'sortkey':
68 $this->addFields('cl_sortkey');
69 $fld_sortkey = true;
70 break;
71 case 'timestamp':
72 $this->addFields('cl_timestamp');
73 $fld_timestamp = true;
74 break;
75 default :
76 ApiBase :: dieDebug(__METHOD__, "Unknown prop=$p");
77 }
78 }
79 }
80
81 $this->addTables('categorylinks');
82 $this->addWhereFld('cl_from', array_keys($this->getPageSet()->getGoodTitles()));
83 if(!is_null($params['continue'])) {
84 $cont = explode('|', $params['continue']);
85 if(count($cont) != 2)
86 $this->dieUsage("Invalid continue param. You should pass the " .
87 "original value returned by the previous query", "_badcontinue");
88 $clfrom = intval($cont[0]);
89 $clto = $this->getDb()->strencode($cont[1]);
90 $this->addWhere("cl_from > $clfrom OR ".
91 "(cl_from = $clfrom AND ".
92 "cl_to >= '$clto')");
93 }
94 # Don't order by cl_from if it's constant in the WHERE clause
95 if(count($this->getPageSet()->getGoodTitles()) == 1)
96 $this->addOption('ORDER BY', 'cl_to');
97 else
98 $this->addOption('ORDER BY', "cl_from, cl_to");
99
100 $db = $this->getDB();
101 $res = $this->select(__METHOD__);
102
103 if (is_null($resultPageSet)) {
104
105 $data = array();
106 $lastId = 0; // database has no ID 0
107 $count = 0;
108 while ($row = $db->fetchObject($res)) {
109 if (++$count > $params['limit']) {
110 // We've reached the one extra which shows that
111 // there are additional pages to be had. Stop here...
112 $this->setContinueEnumParameter('continue', "{$row->cl_from}|{$row->cl_to}");
113 break;
114 }
115 if ($lastId != $row->cl_from) {
116 if($lastId != 0) {
117 $this->addPageSubItems($lastId, $data);
118 $data = array();
119 }
120 $lastId = $row->cl_from;
121 }
122
123 $title = Title :: makeTitle(NS_CATEGORY, $row->cl_to);
124
125 $vals = array();
126 ApiQueryBase :: addTitleInfo($vals, $title);
127 if ($fld_sortkey)
128 $vals['sortkey'] = $row->cl_sortkey;
129 if ($fld_timestamp)
130 $vals['timestamp'] = $row->cl_timestamp;
131
132 $data[] = $vals;
133 }
134
135 if($lastId != 0) {
136 $this->addPageSubItems($lastId, $data);
137 }
138
139 } else {
140
141 $titles = array();
142 while ($row = $db->fetchObject($res)) {
143 if (++$count > $params['limit']) {
144 // We've reached the one extra which shows that
145 // there are additional pages to be had. Stop here...
146 $this->setContinueEnumParameter('continue', "{$row->il_from}|{$row->il_to}");
147 break;
148 }
149
150 $titles[] = Title :: makeTitle(NS_CATEGORY, $row->cl_to);
151 }
152 $resultPageSet->populateFromTitles($titles);
153 }
154
155 $db->freeResult($res);
156 }
157
158 public function getAllowedParams() {
159 return array (
160 'prop' => array (
161 ApiBase :: PARAM_ISMULTI => true,
162 ApiBase :: PARAM_TYPE => array (
163 'sortkey',
164 'timestamp',
165 )
166 ),
167 'limit' => array(
168 ApiBase :: PARAM_DFLT => 10,
169 ApiBase :: PARAM_TYPE => 'limit',
170 ApiBase :: PARAM_MIN => 1,
171 ApiBase :: PARAM_MAX => ApiBase :: LIMIT_BIG1,
172 ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
173 ),
174 'continue' => null,
175 );
176 }
177
178 public function getParamDescription() {
179 return array (
180 'prop' => 'Which additional properties to get for each category.',
181 'limit' => 'How many langlinks to return',
182 'continue' => 'When more results are available, use this to continue',
183 );
184 }
185
186 public function getDescription() {
187 return 'List all categories the page(s) belong to';
188 }
189
190 protected function getExamples() {
191 return array (
192 "Get a list of categories [[Albert Einstein]] belongs to:",
193 " api.php?action=query&prop=categories&titles=Albert%20Einstein",
194 "Get information about all categories used in the [[Albert Einstein]]:",
195 " api.php?action=query&generator=categories&titles=Albert%20Einstein&prop=info"
196 );
197 }
198
199 public function getVersion() {
200 return __CLASS__ . ': $Id$';
201 }
202 }