includes/ChangeTags.php

   1 <?php
   2 /**
   3  * Recent changes tagging.
   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  */
  22
  23 class ChangeTags {
  24
  25         /**
  26          * Creates HTML for the given tags
  27          *
  28          * @param string $tags Comma-separated list of tags
  29          * @param string $page A label for the type of action which is being displayed,
  30          *                     for example: 'history', 'contributions' or 'newpages'
  31          *
  32          * @return Array with two items: (html, classes)
  33          *            - html: String: HTML for displaying the tags (empty string when param $tags is empty)
  34          *            - classes: Array of strings: CSS classes used in the generated html, one class for each tag
  35          *
  36          */
  37         public static function formatSummaryRow( $tags, $page ) {
  38                 global $wgLang;
  39
  40                 if ( !$tags ) {
  41                         return array( '', array() );
  42                 }
  43
  44                 $classes = array();
  45
  46                 $tags = explode( ',', $tags );
  47                 $displayTags = array();
  48                 foreach ( $tags as $tag ) {
  49                         $displayTags[] = Xml::tags(
  50                                 'span',
  51                                 array( 'class' => 'mw-tag-marker ' .
  52                                                                 Sanitizer::escapeClass( "mw-tag-marker-$tag" ) ),
  53                                 self::tagDescription( $tag )
  54                         );
  55                         $classes[] = Sanitizer::escapeClass( "mw-tag-$tag" );
  56                 }
  57                 $markers = wfMessage( 'tag-list-wrapper' )
  58                         ->numParams( count( $displayTags ) )
  59                         ->rawParams( $wgLang->commaList( $displayTags ) )
  60                         ->parse();
  61                 $markers = Xml::tags( 'span', array( 'class' => 'mw-tag-markers' ), $markers );
  62
  63                 return array( $markers, $classes );
  64         }
  65
  66         /**
  67          * Get a short description for a tag
  68          *
  69          * @param string $tag tag
  70          *
  71          * @return String: Short description of the tag from "mediawiki:tag-$tag" if this message exists,
  72          *                 html-escaped version of $tag otherwise
  73          */
  74         public static function tagDescription( $tag ) {
  75                 $msg = wfMessage( "tag-$tag" );
  76                 return $msg->exists() ? $msg->parse() : htmlspecialchars( $tag );
  77         }
  78
  79         /**
  80          * Add tags to a change given its rc_id, rev_id and/or log_id
  81          *
  82          * @param string|array $tags Tags to add to the change
  83          * @param $rc_id int: rc_id of the change to add the tags to
  84          * @param $rev_id int: rev_id of the change to add the tags to
  85          * @param $log_id int: log_id of the change to add the tags to
  86          * @param string $params params to put in the ct_params field of table 'change_tag'
  87          *
  88          * @throws MWException
  89          * @return bool: false if no changes are made, otherwise true
  90          *
  91          * @exception MWException when $rc_id, $rev_id and $log_id are all null
  92          */
  93         public static function addTags( $tags, $rc_id = null, $rev_id = null, $log_id = null, $params = null ) {
  94                 if ( !is_array( $tags ) ) {
  95                         $tags = array( $tags );
  96                 }
  97
  98                 $tags = array_filter( $tags ); // Make sure we're submitting all tags...
  99
 100                 if ( !$rc_id && !$rev_id && !$log_id ) {
 101                         throw new MWException( 'At least one of: RCID, revision ID, and log ID MUST be ' .
 102                                 'specified when adding a tag to a change!' );
 103                 }
 104
 105                 $dbr = wfGetDB( DB_SLAVE );
 106
 107                 // Might as well look for rcids and so on.
 108                 if ( !$rc_id ) {
 109                         $dbr = wfGetDB( DB_MASTER ); // Info might be out of date, somewhat fractionally, on slave.
 110                         if ( $log_id ) {
 111                                 $rc_id = $dbr->selectField( 'recentchanges', 'rc_id', array( 'rc_logid' => $log_id ), __METHOD__ );
 112                         } elseif ( $rev_id ) {
 113                                 $rc_id = $dbr->selectField( 'recentchanges', 'rc_id', array( 'rc_this_oldid' => $rev_id ), __METHOD__ );
 114                         }
 115                 } elseif ( !$log_id && !$rev_id ) {
 116                         $dbr = wfGetDB( DB_MASTER ); // Info might be out of date, somewhat fractionally, on slave.
 117                         $log_id = $dbr->selectField( 'recentchanges', 'rc_logid', array( 'rc_id' => $rc_id ), __METHOD__ );
 118                         $rev_id = $dbr->selectField( 'recentchanges', 'rc_this_oldid', array( 'rc_id' => $rc_id ), __METHOD__ );
 119                 }
 120
 121                 $tsConds = array_filter( array( 'ts_rc_id' => $rc_id, 'ts_rev_id' => $rev_id, 'ts_log_id' => $log_id ) );
 122
 123                 ## Update the summary row.
 124                 $prevTags = $dbr->selectField( 'tag_summary', 'ts_tags', $tsConds, __METHOD__ );
 125                 $prevTags = $prevTags ? $prevTags : '';
 126                 $prevTags = array_filter( explode( ',', $prevTags ) );
 127                 $newTags = array_unique( array_merge( $prevTags, $tags ) );
 128                 sort( $prevTags );
 129                 sort( $newTags );
 130
 131                 if ( $prevTags == $newTags ) {
 132                         // No change.
 133                         return false;
 134                 }
 135
 136                 $dbw = wfGetDB( DB_MASTER );
 137                 $dbw->replace(
 138                         'tag_summary',
 139                         array( 'ts_rev_id', 'ts_rc_id', 'ts_log_id' ),
 140                         array_filter( array_merge( $tsConds, array( 'ts_tags' => implode( ',', $newTags ) ) ) ),
 141                         __METHOD__
 142                 );
 143
 144                 // Insert the tags rows.
 145                 $tagsRows = array();
 146                 foreach ( $tags as $tag ) { // Filter so we don't insert NULLs as zero accidentally.
 147                         $tagsRows[] = array_filter(
 148                                 array(
 149                                         'ct_tag' => $tag,
 150                                         'ct_rc_id' => $rc_id,
 151                                         'ct_log_id' => $log_id,
 152                                         'ct_rev_id' => $rev_id,
 153                                         'ct_params' => $params
 154                                 )
 155                         );
 156                 }
 157
 158                 $dbw->insert( 'change_tag', $tagsRows, __METHOD__, array( 'IGNORE' ) );
 159
 160                 return true;
 161         }
 162
 163         /**
 164          * Applies all tags-related changes to a query.
 165          * Handles selecting tags, and filtering.
 166          * Needs $tables to be set up properly, so we can figure out which join conditions to use.
 167          *
 168          * @param string|array $tables Table names, see DatabaseBase::select
 169          * @param string|array $fields Fields used in query, see DatabaseBase::select
 170          * @param string|array $conds conditions used in query, see DatabaseBase::select
 171          * @param $join_conds Array: join conditions, see DatabaseBase::select
 172          * @param array $options options, see Database::select
 173          * @param bool|string $filter_tag Tag to select on
 174          *
 175          * @throws MWException When unable to determine appropriate JOIN condition for tagging
 176          */
 177         public static function modifyDisplayQuery( &$tables, &$fields, &$conds,
 178                                                                                 &$join_conds, &$options, $filter_tag = false ) {
 179                 global $wgRequest, $wgUseTagFilter;
 180
 181                 if ( $filter_tag === false ) {
 182                         $filter_tag = $wgRequest->getVal( 'tagfilter' );
 183                 }
 184
 185                 // Figure out which conditions can be done.
 186                 if ( in_array( 'recentchanges', $tables ) ) {
 187                         $join_cond = 'rc_id';
 188                 } elseif ( in_array( 'logging', $tables ) ) {
 189                         $join_cond = 'log_id';
 190                 } elseif ( in_array( 'revision', $tables ) ) {
 191                         $join_cond = 'rev_id';
 192                 } else {
 193                         throw new MWException( 'Unable to determine appropriate JOIN condition for tagging.' );
 194                 }
 195
 196                 $fields['ts_tags'] = wfGetDB( DB_SLAVE )->buildGroupConcatField(
 197                         ',', 'change_tag', 'ct_tag', "ct_$join_cond=$join_cond"
 198                 );
 199
 200                 if ( $wgUseTagFilter && $filter_tag ) {
 201                         // Somebody wants to filter on a tag.
 202                         // Add an INNER JOIN on change_tag
 203
 204                         $tables[] = 'change_tag';
 205                         $join_conds['change_tag'] = array( 'INNER JOIN', "ct_$join_cond=$join_cond" );
 206                         $conds['ct_tag'] = $filter_tag;
 207                 }
 208         }
 209
 210         /**
 211          * Build a text box to select a change tag
 212          *
 213          * @param string $selected tag to select by default
 214          * @param $fullForm Boolean:
 215          *        - if false, then it returns an array of (label, form).
 216          *        - if true, it returns an entire form around the selector.
 217          * @param $title Title object to send the form to.
 218          *        Used when, and only when $fullForm is true.
 219          * @return String or array:
 220          *        - if $fullForm is false: Array with
 221          *        - if $fullForm is true: String, html fragment
 222          */
 223         public static function buildTagFilterSelector( $selected = '', $fullForm = false, Title $title = null ) {
 224                 global $wgUseTagFilter;
 225
 226                 if ( !$wgUseTagFilter || !count( self::listDefinedTags() ) ) {
 227                         return $fullForm ? '' : array();
 228                 }
 229
 230                 $data = array( Html::rawElement( 'label', array( 'for' => 'tagfilter' ), wfMessage( 'tag-filter' )->parse() ),
 231                         Xml::input( 'tagfilter', 20, $selected, array( 'class' => 'mw-tagfilter-input', 'id' => 'tagfilter' ) ) );
 232
 233                 if ( !$fullForm ) {
 234                         return $data;
 235                 }
 236
 237                 $html = implode( '&#160;', $data );
 238                 $html .= "\n" . Xml::element( 'input', array( 'type' => 'submit', 'value' => wfMessage( 'tag-filter-submit' )->text() ) );
 239                 $html .= "\n" . Html::hidden( 'title', $title->getPrefixedText() );
 240                 $html = Xml::tags( 'form', array( 'action' => $title->getLocalURL(), 'class' => 'mw-tagfilter-form', 'method' => 'get' ), $html );
 241
 242                 return $html;
 243         }
 244
 245         /**
 246          * Basically lists defined tags which count even if they aren't applied to anything.
 247          * Tags on items in table 'change_tag' which are not (or no longer) in table 'valid_tag'
 248          * are not included.
 249          *
 250          * Tries memcached first.
 251          *
 252          * @return Array of strings: tags
 253          */
 254         public static function listDefinedTags() {
 255                 // Caching...
 256                 global $wgMemc;
 257                 $key = wfMemcKey( 'valid-tags' );
 258                 $tags = $wgMemc->get( $key );
 259                 if ( $tags ) {
 260                         return $tags;
 261                 }
 262
 263                 $emptyTags = array();
 264
 265                 // Some DB stuff
 266                 $dbr = wfGetDB( DB_SLAVE );
 267                 $res = $dbr->select( 'valid_tag', 'vt_tag', array(), __METHOD__ );
 268                 foreach ( $res as $row ) {
 269                         $emptyTags[] = $row->vt_tag;
 270                 }
 271
 272                 wfRunHooks( 'ListDefinedTags', array( &$emptyTags ) );
 273
 274                 $emptyTags = array_filter( array_unique( $emptyTags ) );
 275
 276                 // Short-term caching.
 277                 $wgMemc->set( $key, $emptyTags, 300 );
 278                 return $emptyTags;
 279         }
 280
 281         /**
 282          * Returns a map of any tags used on the wiki to number of edits
 283          * tagged with them, ordered descending by the hitcount.
 284          *
 285          * @return array Array of string => int
 286          */
 287         public static function tagUsageStatistics() {
 288                 $out = array();
 289
 290                 $dbr = wfGetDB( DB_SLAVE );
 291                 $res = $dbr->select(
 292                         'change_tag',
 293                         array( 'ct_tag', 'hitcount' => 'count(*)' ),
 294                         array(),
 295                         __METHOD__,
 296                         array( 'GROUP BY' => 'ct_tag', 'ORDER BY' => 'hitcount DESC' )
 297                 );
 298
 299                 foreach ( $res as $row ) {
 300                         $out[$row->ct_tag] = $row->hitcount;
 301                 }
 302                 foreach ( self::listDefinedTags() as $tag ) {
 303                         if ( !isset( $out[$tag] ) ) {
 304                                 $out[$tag] = 0;
 305                         }
 306                 }
 307
 308                 return $out;
 309         }
 310 }