includes/ChangeTags.php

   1 <?php
   2 /**
   3  * Functions related to change tags.
   4  *
   5  * @file
   6  */
   7 class ChangeTags {
   8
   9         /**
  10          * Creates HTML for the given tags
  11          *
  12          * @param $tags String: Comma-separated list of tags
  13          * @param $page String: A label for the type of action which is being displayed,
  14          *                     for example: 'history', 'contributions' or 'newpages'
  15          *
  16          * @return Array with two items: (html, classes)
  17          *            - html: String: HTML for displaying the tags (empty string when param $tags is empty)
  18          *            - classes: Array of strings: CSS classes used in the generated html, one class for each tag
  19          *
  20          */
  21         static function formatSummaryRow( $tags, $page ) {
  22                 if( !$tags )
  23                         return array( '', array() );
  24
  25                 $classes = array();
  26
  27                 $tags = explode( ',', $tags );
  28                 $displayTags = array();
  29                 foreach( $tags as $tag ) {
  30                         $displayTags[] = Xml::tags(
  31                                 'span',
  32                                 array( 'class' => 'mw-tag-marker ' .
  33                                                                 Sanitizer::escapeClass( "mw-tag-marker-$tag" ) ),
  34                                 self::tagDescription( $tag )
  35                         );
  36                         $classes[] = Sanitizer::escapeClass( "mw-tag-$tag" );
  37                 }
  38                 $markers = '(' . implode( ', ', $displayTags ) . ')';
  39                 $markers = Xml::tags( 'span', array( 'class' => 'mw-tag-markers' ), $markers );
  40
  41                 return array( $markers, $classes );
  42         }
  43
  44         /**
  45          * Get a short description for a tag
  46          *
  47          * @param $tag String: tag
  48          *
  49          * @return String: Short description of the tag from "mediawiki:tag-$tag" if this message exists,
  50          *                 html-escaped version of $tag otherwise
  51          */
  52         static function tagDescription( $tag ) {
  53                 $msg = wfMessage( "tag-$tag" );
  54                 return $msg->exists() ? $msg->parse() : htmlspecialchars( $tag );
  55         }
  56
  57         /**
  58          * Add tags to a change given its rc_id, rev_id and/or log_id
  59          *
  60          * @param $tags String|Array: Tags to add to the change
  61          * @param $rc_id int: rc_id of the change to add the tags to
  62          * @param $rev_id int: rev_id of the change to add the tags to
  63          * @param $log_id int: log_id of the change to add the tags to
  64          * @param $params String: params to put in the ct_params field of tabel 'change_tag'
  65          *
  66          * @return bool: false if no changes are made, otherwise true
  67          *
  68          * @exception MWException when $rc_id, $rev_id and $log_id are all null
  69          */
  70         static function addTags( $tags, $rc_id = null, $rev_id = null, $log_id = null, $params = null ) {
  71                 if ( !is_array( $tags ) ) {
  72                         $tags = array( $tags );
  73                 }
  74
  75                 $tags = array_filter( $tags ); // Make sure we're submitting all tags...
  76
  77                 if( !$rc_id && !$rev_id && !$log_id ) {
  78                         throw new MWException( "At least one of: RCID, revision ID, and log ID MUST be specified when adding a tag to a change!" );
  79                 }
  80
  81                 $dbr = wfGetDB( DB_SLAVE );
  82
  83                 // Might as well look for rcids and so on.
  84                 if( !$rc_id ) {
  85                         $dbr = wfGetDB( DB_MASTER ); // Info might be out of date, somewhat fractionally, on slave.
  86                         if( $log_id ) {
  87                                 $rc_id = $dbr->selectField( 'recentchanges', 'rc_id', array( 'rc_logid' => $log_id ), __METHOD__ );
  88                         } elseif( $rev_id ) {
  89                                 $rc_id = $dbr->selectField( 'recentchanges', 'rc_id', array( 'rc_this_oldid' => $rev_id ), __METHOD__ );
  90                         }
  91                 } elseif( !$log_id && !$rev_id ) {
  92                         $dbr = wfGetDB( DB_MASTER ); // Info might be out of date, somewhat fractionally, on slave.
  93                         $log_id = $dbr->selectField( 'recentchanges', 'rc_logid', array( 'rc_id' => $rc_id ), __METHOD__ );
  94                         $rev_id = $dbr->selectField( 'recentchanges', 'rc_this_oldid', array( 'rc_id' => $rc_id ), __METHOD__ );
  95                 }
  96
  97                 $tsConds = array_filter( array( 'ts_rc_id' => $rc_id, 'ts_rev_id' => $rev_id, 'ts_log_id' => $log_id ) );
  98
  99                 ## Update the summary row.
 100                 $prevTags = $dbr->selectField( 'tag_summary', 'ts_tags', $tsConds, __METHOD__ );
 101                 $prevTags = $prevTags ? $prevTags : '';
 102                 $prevTags = array_filter( explode( ',', $prevTags ) );
 103                 $newTags = array_unique( array_merge( $prevTags, $tags ) );
 104                 sort( $prevTags );
 105                 sort( $newTags );
 106
 107                 if ( $prevTags == $newTags ) {
 108                         // No change.
 109                         return false;
 110                 }
 111
 112                 $dbw = wfGetDB( DB_MASTER );
 113                 $dbw->replace(
 114                         'tag_summary',
 115                         array( 'ts_rev_id', 'ts_rc_id', 'ts_log_id' ),
 116                         array_filter( array_merge( $tsConds, array( 'ts_tags' => implode( ',', $newTags ) ) ) ),
 117                         __METHOD__
 118                 );
 119
 120                 // Insert the tags rows.
 121                 $tagsRows = array();
 122                 foreach( $tags as $tag ) { // Filter so we don't insert NULLs as zero accidentally.
 123                         $tagsRows[] = array_filter(
 124                                 array(
 125                                         'ct_tag' => $tag,
 126                                         'ct_rc_id' => $rc_id,
 127                                         'ct_log_id' => $log_id,
 128                                         'ct_rev_id' => $rev_id,
 129                                         'ct_params' => $params
 130                                 )
 131                         );
 132                 }
 133
 134                 $dbw->insert( 'change_tag', $tagsRows, __METHOD__, array( 'IGNORE' ) );
 135
 136                 return true;
 137         }
 138
 139         /**
 140          * Applies all tags-related changes to a query.
 141          * Handles selecting tags, and filtering.
 142          * Needs $tables to be set up properly, so we can figure out which join conditions to use.
 143          *
 144          * @param $tables String|Array: Tabel names, see DatabaseBase::select
 145          * @param $fields String|Array: Fields used in query, see DatabaseBase::select
 146          * @param $conds String|Array: conditions used in query, see DatabaseBase::select
 147          * @param $join_conds Array: join conditions, see DatabaseBase::select
 148          * @param $options Array: options, see Database::select
 149          * @param $filter_tag String: tag to select on
 150          *
 151          * @exception MWException when unable to determine appropriate JOIN condition for tagging
 152          *
 153          */
 154         static function modifyDisplayQuery( &$tables, &$fields,  &$conds,
 155                                                                                 &$join_conds, &$options, $filter_tag = false ) {
 156                 global $wgRequest, $wgUseTagFilter;
 157
 158                 if( $filter_tag === false ) {
 159                         $filter_tag = $wgRequest->getVal( 'tagfilter' );
 160                 }
 161
 162                 // Figure out which conditions can be done.
 163                 if ( in_array( 'recentchanges', $tables ) ) {
 164                         $join_cond = 'rc_id';
 165                 } elseif( in_array( 'logging', $tables ) ) {
 166                         $join_cond = 'log_id';
 167                 } elseif ( in_array( 'revision', $tables ) ) {
 168                         $join_cond = 'rev_id';
 169                 } else {
 170                         throw new MWException( 'Unable to determine appropriate JOIN condition for tagging.' );
 171                 }
 172
 173                 // JOIN on tag_summary
 174                 $tables[] = 'tag_summary';
 175                 $join_conds['tag_summary'] = array( 'LEFT JOIN', "ts_$join_cond=$join_cond" );
 176                 $fields[] = 'ts_tags';
 177
 178                 if( $wgUseTagFilter && $filter_tag ) {
 179                         // Somebody wants to filter on a tag.
 180                         // Add an INNER JOIN on change_tag
 181
 182                         // FORCE INDEX -- change_tags will almost ALWAYS be the correct query plan.
 183                         global $wgOldChangeTagsIndex;
 184                         $index = $wgOldChangeTagsIndex ? 'ct_tag' : 'change_tag_tag_id';
 185                         $options['USE INDEX'] = array( 'change_tag' => $index );
 186                         unset( $options['FORCE INDEX'] );
 187                         $tables[] = 'change_tag';
 188                         $join_conds['change_tag'] = array( 'INNER JOIN', "ct_$join_cond=$join_cond" );
 189                         $conds['ct_tag'] = $filter_tag;
 190                 }
 191         }
 192
 193         /**
 194          * Build a text box to select a change tag
 195          *
 196          * @param $selected String: tag to select by default
 197          * @param $fullForm Boolean:
 198          *        - if false, then it returns an array of (label, form).
 199          *        - if true, it returns an entire form around the selector.
 200          * @param $title Title object to send the form to.
 201          *        Used when, and only when $fullForm is true.
 202          * @return String or array:
 203          *        - if $fullForm is false: Array with
 204          *        - if $fullForm is true: String, html fragment
 205          */
 206         public static function buildTagFilterSelector( $selected='', $fullForm = false, Title $title = null ) {
 207                 global $wgUseTagFilter;
 208
 209                 if ( !$wgUseTagFilter || !count( self::listDefinedTags() ) )
 210                         return $fullForm ? '' : array();
 211
 212                 $data = array( Html::rawElement( 'label', array( 'for' => 'tagfilter' ), wfMsgExt( 'tag-filter', 'parseinline' ),
 213                                 Xml::input( 'tagfilter', 20, $selected, array( 'class' => 'tagfilter-input' ) ) ) );
 214
 215                 if ( !$fullForm ) {
 216                         return $data;
 217                 }
 218
 219                 $html = implode( '&#160;', $data );
 220                 $html .= "\n" . Xml::element( 'input', array( 'type' => 'submit', 'value' => wfMsg( 'tag-filter-submit' ) ) );
 221                 $html .= "\n" . Html::hidden( 'title', $title->getPrefixedText() );
 222                 $html = Xml::tags( 'form', array( 'action' => $title->getLocalURL(), 'class' => 'tagfilter-form', 'method' => 'get' ), $html );
 223
 224                 return $html;
 225         }
 226
 227         /**
 228          * Basically lists defined tags which count even if they aren't applied to anything.
 229          * Tags on items in table 'change_tag' which are not (or no longer) in table 'valid_tag'
 230          * are not included.
 231          *
 232          * Tries memcached first.
 233          *
 234          * @return Array of strings: tags
 235          */
 236         static function listDefinedTags() {
 237                 // Caching...
 238                 global $wgMemc;
 239                 $key = wfMemcKey( 'valid-tags' );
 240                 $tags = $wgMemc->get( $key );
 241                 if ( $tags ) {
 242                         return $tags;
 243                 }
 244
 245                 $emptyTags = array();
 246
 247                 // Some DB stuff
 248                 $dbr = wfGetDB( DB_SLAVE );
 249                 $res = $dbr->select( 'valid_tag', 'vt_tag', array(), __METHOD__ );
 250                 foreach ( $res as $row ) {
 251                         $emptyTags[] = $row->vt_tag;
 252                 }
 253
 254                 wfRunHooks( 'ListDefinedTags', array( &$emptyTags ) );
 255
 256                 $emptyTags = array_filter( array_unique( $emptyTags ) );
 257
 258                 // Short-term caching.
 259                 $wgMemc->set( $key, $emptyTags, 300 );
 260                 return $emptyTags;
 261         }
 262 }