AuthManager: Commit transaction after auto-creating a user
[mediawiki.git] / includes / Category.php
blob28b566a7f99ff2dd6f3b0cef13edea93ec7db130
1 <?php
2 /**
3 * Representation for a category.
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.
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.
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
20 * @file
21 * @author Simetrical
24 /**
25 * Category objects are immutable, strictly speaking. If you call methods that change the database,
26 * like to refresh link counts, the objects will be appropriately reinitialized.
27 * Member variables are lazy-initialized.
29 * @todo Move some stuff from CategoryPage.php to here, and use that.
31 class Category {
32 /** Name of the category, normalized to DB-key form */
33 private $mName = null;
34 private $mID = null;
35 /**
36 * Category page title
37 * @var Title
39 private $mTitle = null;
40 /** Counts of membership (cat_pages, cat_subcats, cat_files) */
41 private $mPages = null, $mSubcats = null, $mFiles = null;
43 private function __construct() {
46 /**
47 * Set up all member variables using a database query.
48 * @throws MWException
49 * @return bool True on success, false on failure.
51 protected function initialize() {
52 if ( $this->mName === null && $this->mID === null ) {
53 throw new MWException( __METHOD__ . ' has both names and IDs null' );
54 } elseif ( $this->mID === null ) {
55 $where = [ 'cat_title' => $this->mName ];
56 } elseif ( $this->mName === null ) {
57 $where = [ 'cat_id' => $this->mID ];
58 } else {
59 # Already initialized
60 return true;
63 $dbr = wfGetDB( DB_SLAVE );
64 $row = $dbr->selectRow(
65 'category',
66 [ 'cat_id', 'cat_title', 'cat_pages', 'cat_subcats', 'cat_files' ],
67 $where,
68 __METHOD__
71 if ( !$row ) {
72 # Okay, there were no contents. Nothing to initialize.
73 if ( $this->mTitle ) {
74 # If there is a title object but no record in the category table,
75 # treat this as an empty category.
76 $this->mID = false;
77 $this->mName = $this->mTitle->getDBkey();
78 $this->mPages = 0;
79 $this->mSubcats = 0;
80 $this->mFiles = 0;
82 return true;
83 } else {
84 return false; # Fail
88 $this->mID = $row->cat_id;
89 $this->mName = $row->cat_title;
90 $this->mPages = $row->cat_pages;
91 $this->mSubcats = $row->cat_subcats;
92 $this->mFiles = $row->cat_files;
94 # (bug 13683) If the count is negative, then 1) it's obviously wrong
95 # and should not be kept, and 2) we *probably* don't have to scan many
96 # rows to obtain the correct figure, so let's risk a one-time recount.
97 if ( $this->mPages < 0 || $this->mSubcats < 0 || $this->mFiles < 0 ) {
98 $this->mPages = max( $this->mPages, 0 );
99 $this->mSubcats = max( $this->mSubcats, 0 );
100 $this->mFiles = max( $this->mFiles, 0 );
102 DeferredUpdates::addCallableUpdate( [ $this, 'refreshCounts' ] );
105 return true;
109 * Factory function.
111 * @param array $name A category name (no "Category:" prefix). It need
112 * not be normalized, with spaces replaced by underscores.
113 * @return mixed Category, or false on a totally invalid name
115 public static function newFromName( $name ) {
116 $cat = new self();
117 $title = Title::makeTitleSafe( NS_CATEGORY, $name );
119 if ( !is_object( $title ) ) {
120 return false;
123 $cat->mTitle = $title;
124 $cat->mName = $title->getDBkey();
126 return $cat;
130 * Factory function.
132 * @param Title $title Title for the category page
133 * @return Category|bool On a totally invalid name
135 public static function newFromTitle( $title ) {
136 $cat = new self();
138 $cat->mTitle = $title;
139 $cat->mName = $title->getDBkey();
141 return $cat;
145 * Factory function.
147 * @param int $id A category id
148 * @return Category
150 public static function newFromID( $id ) {
151 $cat = new self();
152 $cat->mID = intval( $id );
153 return $cat;
157 * Factory function, for constructing a Category object from a result set
159 * @param object $row Result set row, must contain the cat_xxx fields. If the
160 * fields are null, the resulting Category object will represent an empty
161 * category if a title object was given. If the fields are null and no
162 * title was given, this method fails and returns false.
163 * @param Title $title Optional title object for the category represented by
164 * the given row. May be provided if it is already known, to avoid having
165 * to re-create a title object later.
166 * @return Category
168 public static function newFromRow( $row, $title = null ) {
169 $cat = new self();
170 $cat->mTitle = $title;
172 # NOTE: the row often results from a LEFT JOIN on categorylinks. This may result in
173 # all the cat_xxx fields being null, if the category page exists, but nothing
174 # was ever added to the category. This case should be treated link an empty
175 # category, if possible.
177 if ( $row->cat_title === null ) {
178 if ( $title === null ) {
179 # the name is probably somewhere in the row, for example as page_title,
180 # but we can't know that here...
181 return false;
182 } else {
183 # if we have a title object, fetch the category name from there
184 $cat->mName = $title->getDBkey();
187 $cat->mID = false;
188 $cat->mSubcats = 0;
189 $cat->mPages = 0;
190 $cat->mFiles = 0;
191 } else {
192 $cat->mName = $row->cat_title;
193 $cat->mID = $row->cat_id;
194 $cat->mSubcats = $row->cat_subcats;
195 $cat->mPages = $row->cat_pages;
196 $cat->mFiles = $row->cat_files;
199 return $cat;
203 * @return mixed DB key name, or false on failure
205 public function getName() {
206 return $this->getX( 'mName' );
210 * @return mixed Category ID, or false on failure
212 public function getID() {
213 return $this->getX( 'mID' );
217 * @return mixed Total number of member pages, or false on failure
219 public function getPageCount() {
220 return $this->getX( 'mPages' );
224 * @return mixed Number of subcategories, or false on failure
226 public function getSubcatCount() {
227 return $this->getX( 'mSubcats' );
231 * @return mixed Number of member files, or false on failure
233 public function getFileCount() {
234 return $this->getX( 'mFiles' );
238 * @return Title|bool Title for this category, or false on failure.
240 public function getTitle() {
241 if ( $this->mTitle ) {
242 return $this->mTitle;
245 if ( !$this->initialize() ) {
246 return false;
249 $this->mTitle = Title::makeTitleSafe( NS_CATEGORY, $this->mName );
250 return $this->mTitle;
254 * Fetch a TitleArray of up to $limit category members, beginning after the
255 * category sort key $offset.
256 * @param int $limit
257 * @param string $offset
258 * @return TitleArray TitleArray object for category members.
260 public function getMembers( $limit = false, $offset = '' ) {
262 $dbr = wfGetDB( DB_SLAVE );
264 $conds = [ 'cl_to' => $this->getName(), 'cl_from = page_id' ];
265 $options = [ 'ORDER BY' => 'cl_sortkey' ];
267 if ( $limit ) {
268 $options['LIMIT'] = $limit;
271 if ( $offset !== '' ) {
272 $conds[] = 'cl_sortkey > ' . $dbr->addQuotes( $offset );
275 $result = TitleArray::newFromResult(
276 $dbr->select(
277 [ 'page', 'categorylinks' ],
278 [ 'page_id', 'page_namespace', 'page_title', 'page_len',
279 'page_is_redirect', 'page_latest' ],
280 $conds,
281 __METHOD__,
282 $options
286 return $result;
290 * Generic accessor
291 * @param string $key
292 * @return bool
294 private function getX( $key ) {
295 if ( !$this->initialize() ) {
296 return false;
298 return $this->{$key};
302 * Refresh the counts for this category.
304 * @return bool True on success, false on failure
306 public function refreshCounts() {
307 if ( wfReadOnly() ) {
308 return false;
311 # If we have just a category name, find out whether there is an
312 # existing row. Or if we have just an ID, get the name, because
313 # that's what categorylinks uses.
314 if ( !$this->initialize() ) {
315 return false;
318 $dbw = wfGetDB( DB_MASTER );
319 $dbw->startAtomic( __METHOD__ );
321 $cond1 = $dbw->conditional( [ 'page_namespace' => NS_CATEGORY ], 1, 'NULL' );
322 $cond2 = $dbw->conditional( [ 'page_namespace' => NS_FILE ], 1, 'NULL' );
323 $result = $dbw->selectRow(
324 [ 'categorylinks', 'page' ],
325 [ 'pages' => 'COUNT(*)',
326 'subcats' => "COUNT($cond1)",
327 'files' => "COUNT($cond2)"
329 [ 'cl_to' => $this->mName, 'page_id = cl_from' ],
330 __METHOD__,
331 [ 'LOCK IN SHARE MODE' ]
334 if ( $this->mID ) {
335 # The category row already exists, so do a plain UPDATE instead
336 # of INSERT...ON DUPLICATE KEY UPDATE to avoid creating a gap
337 # in the cat_id sequence. The row may or may not be "affected".
338 $dbw->update(
339 'category',
341 'cat_pages' => $result->pages,
342 'cat_subcats' => $result->subcats,
343 'cat_files' => $result->files
345 [ 'cat_title' => $this->mName ],
346 __METHOD__
348 } else {
349 $dbw->upsert(
350 'category',
352 'cat_title' => $this->mName,
353 'cat_pages' => $result->pages,
354 'cat_subcats' => $result->subcats,
355 'cat_files' => $result->files
357 [ 'cat_title' ],
359 'cat_pages' => $result->pages,
360 'cat_subcats' => $result->subcats,
361 'cat_files' => $result->files
363 __METHOD__
367 $dbw->endAtomic( __METHOD__ );
369 # Now we should update our local counts.
370 $this->mPages = $result->pages;
371 $this->mSubcats = $result->subcats;
372 $this->mFiles = $result->files;
374 return true;