includes/resourceloader/ResourceLoaderWikiModule.php

   1 <?php
   2 /**
   3  * Abstraction for ResourceLoader modules that pull from wiki pages.
   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  * @author Trevor Parscal
  22  * @author Roan Kattouw
  23  */
  24
  25 /**
  26  * Abstraction for ResourceLoader modules which pull from wiki pages
  27  *
  28  * This can only be used for wiki pages in the MediaWiki and User namespaces,
  29  * because of its dependence on the functionality of Title::isCssJsSubpage.
  30  *
  31  * This module supports being used as a placeholder for a module on a remote wiki.
  32  * To do so, getDB() must be overloaded to return a foreign database object that
  33  * allows local wikis to query page metadata.
  34  *
  35  * Safe for calls on local wikis are:
  36  * - Option getters:
  37  *   - getGroup()
  38  *   - getPosition()
  39  *   - getPages()
  40  * - Basic methods that strictly involve the foreign database
  41  *   - getDB()
  42  *   - isKnownEmpty()
  43  *   - getTitleInfo()
  44  */
  45 class ResourceLoaderWikiModule extends ResourceLoaderModule {
  46         /** @var string Position on the page to load this module at */
  47         protected $position = 'bottom';
  48
  49         // Origin defaults to users with sitewide authority
  50         protected $origin = self::ORIGIN_USER_SITEWIDE;
  51
  52         // In-process cache for title info
  53         protected $titleInfo = [];
  54
  55         // List of page names that contain CSS
  56         protected $styles = [];
  57
  58         // List of page names that contain JavaScript
  59         protected $scripts = [];
  60
  61         // Group of module
  62         protected $group;
  63
  64         /**
  65          * @param array $options For back-compat, this can be omitted in favour of overwriting getPages.
  66          */
  67         public function __construct( array $options = null ) {
  68                 if ( is_null( $options ) ) {
  69                         return;
  70                 }
  71
  72                 foreach ( $options as $member => $option ) {
  73                         switch ( $member ) {
  74                                 case 'position':
  75                                 case 'styles':
  76                                 case 'scripts':
  77                                 case 'group':
  78                                 case 'targets':
  79                                         $this->{$member} = $option;
  80                                         break;
  81                         }
  82                 }
  83         }
  84
  85         /**
  86          * Subclasses should return an associative array of resources in the module.
  87          * Keys should be the title of a page in the MediaWiki or User namespace.
  88          *
  89          * Values should be a nested array of options.  The supported keys are 'type' and
  90          * (CSS only) 'media'.
  91          *
  92          * For scripts, 'type' should be 'script'.
  93          *
  94          * For stylesheets, 'type' should be 'style'.
  95          * There is an optional media key, the value of which can be the
  96          * medium ('screen', 'print', etc.) of the stylesheet.
  97          *
  98          * @param ResourceLoaderContext $context
  99          * @return array
 100          */
 101         protected function getPages( ResourceLoaderContext $context ) {
 102                 $config = $this->getConfig();
 103                 $pages = [];
 104
 105                 // Filter out pages from origins not allowed by the current wiki configuration.
 106                 if ( $config->get( 'UseSiteJs' ) ) {
 107                         foreach ( $this->scripts as $script ) {
 108                                 $pages[$script] = [ 'type' => 'script' ];
 109                         }
 110                 }
 111
 112                 if ( $config->get( 'UseSiteCss' ) ) {
 113                         foreach ( $this->styles as $style ) {
 114                                 $pages[$style] = [ 'type' => 'style' ];
 115                         }
 116                 }
 117
 118                 return $pages;
 119         }
 120
 121         /**
 122          * Get group name
 123          *
 124          * @return string
 125          */
 126         public function getGroup() {
 127                 return $this->group;
 128         }
 129
 130         /**
 131          * Get the Database object used in getTitleInfo().
 132          *
 133          * Defaults to the local slave DB. Subclasses may want to override this to return a foreign
 134          * database object, or null if getTitleInfo() shouldn't access the database.
 135          *
 136          * NOTE: This ONLY works for getTitleInfo() and isKnownEmpty(), NOT FOR ANYTHING ELSE.
 137          * In particular, it doesn't work for getContent() or getScript() etc.
 138          *
 139          * @return IDatabase|null
 140          */
 141         protected function getDB() {
 142                 return wfGetDB( DB_SLAVE );
 143         }
 144
 145         /**
 146          * @param string $title
 147          * @return null|string
 148          */
 149         protected function getContent( $titleText ) {
 150                 $title = Title::newFromText( $titleText );
 151                 if ( !$title ) {
 152                         return null;
 153                 }
 154
 155                 $handler = ContentHandler::getForTitle( $title );
 156                 if ( $handler->isSupportedFormat( CONTENT_FORMAT_CSS ) ) {
 157                         $format = CONTENT_FORMAT_CSS;
 158                 } elseif ( $handler->isSupportedFormat( CONTENT_FORMAT_JAVASCRIPT ) ) {
 159                         $format = CONTENT_FORMAT_JAVASCRIPT;
 160                 } else {
 161                         return null;
 162                 }
 163
 164                 $revision = Revision::newFromTitle( $title, false, Revision::READ_NORMAL );
 165                 if ( !$revision ) {
 166                         return null;
 167                 }
 168
 169                 $content = $revision->getContent( Revision::RAW );
 170
 171                 if ( !$content ) {
 172                         wfDebugLog( 'resourceloader', __METHOD__ . ': failed to load content of JS/CSS page!' );
 173                         return null;
 174                 }
 175
 176                 return $content->serialize( $format );
 177         }
 178
 179         /**
 180          * @param ResourceLoaderContext $context
 181          * @return string
 182          */
 183         public function getScript( ResourceLoaderContext $context ) {
 184                 $scripts = '';
 185                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 186                         if ( $options['type'] !== 'script' ) {
 187                                 continue;
 188                         }
 189                         $script = $this->getContent( $titleText );
 190                         if ( strval( $script ) !== '' ) {
 191                                 $script = $this->validateScriptFile( $titleText, $script );
 192                                 $scripts .= ResourceLoader::makeComment( $titleText ) . $script . "\n";
 193                         }
 194                 }
 195                 return $scripts;
 196         }
 197
 198         /**
 199          * @param ResourceLoaderContext $context
 200          * @return array
 201          */
 202         public function getStyles( ResourceLoaderContext $context ) {
 203                 $styles = [];
 204                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 205                         if ( $options['type'] !== 'style' ) {
 206                                 continue;
 207                         }
 208                         $media = isset( $options['media'] ) ? $options['media'] : 'all';
 209                         $style = $this->getContent( $titleText );
 210                         if ( strval( $style ) === '' ) {
 211                                 continue;
 212                         }
 213                         if ( $this->getFlip( $context ) ) {
 214                                 $style = CSSJanus::transform( $style, true, false );
 215                         }
 216                         $style = MemoizedCallable::call( 'CSSMin::remap',
 217                                 [ $style, false, $this->getConfig()->get( 'ScriptPath' ), true ] );
 218                         if ( !isset( $styles[$media] ) ) {
 219                                 $styles[$media] = [];
 220                         }
 221                         $style = ResourceLoader::makeComment( $titleText ) . $style;
 222                         $styles[$media][] = $style;
 223                 }
 224                 return $styles;
 225         }
 226
 227         /**
 228          * Disable module content versioning.
 229          *
 230          * This class does not support generating content outside of a module
 231          * request due to foreign database support.
 232          *
 233          * See getDefinitionSummary() for meta-data versioning.
 234          *
 235          * @return bool
 236          */
 237         public function enableModuleContentVersion() {
 238                 return false;
 239         }
 240
 241         /**
 242          * @param ResourceLoaderContext $context
 243          * @return array
 244          */
 245         public function getDefinitionSummary( ResourceLoaderContext $context ) {
 246                 $summary = parent::getDefinitionSummary( $context );
 247                 $summary[] = [
 248                         'pages' => $this->getPages( $context ),
 249                         // Includes SHA1 of content
 250                         'titleInfo' => $this->getTitleInfo( $context ),
 251                 ];
 252                 return $summary;
 253         }
 254
 255         /**
 256          * @param ResourceLoaderContext $context
 257          * @return bool
 258          */
 259         public function isKnownEmpty( ResourceLoaderContext $context ) {
 260                 $revisions = $this->getTitleInfo( $context );
 261
 262                 // For user modules, don't needlessly load if there are no non-empty pages
 263                 if ( $this->getGroup() === 'user' ) {
 264                         foreach ( $revisions as $revision ) {
 265                                 if ( $revision['rev_len'] > 0 ) {
 266                                         // At least one non-empty page, module should be loaded
 267                                         return false;
 268                                 }
 269                         }
 270                         return true;
 271                 }
 272
 273                 // Bug 68488: For other modules (i.e. ones that are called in cached html output) only check
 274                 // page existance. This ensures that, if some pages in a module are temporarily blanked,
 275                 // we don't end omit the module's script or link tag on some pages.
 276                 return count( $revisions ) === 0;
 277         }
 278
 279         /**
 280          * Get the information about the wiki pages for a given context.
 281          * @param ResourceLoaderContext $context
 282          * @return array Keyed by page name. Contains arrays with 'rev_len' and 'rev_sha1' keys
 283          */
 284         protected function getTitleInfo( ResourceLoaderContext $context ) {
 285                 $dbr = $this->getDB();
 286                 if ( !$dbr ) {
 287                         // We're dealing with a subclass that doesn't have a DB
 288                         return [];
 289                 }
 290
 291                 $pages = $this->getPages( $context );
 292                 $key = implode( '|', array_keys( $pages ) );
 293                 if ( !isset( $this->titleInfo[$key] ) ) {
 294                         $this->titleInfo[$key] = [];
 295                         $batch = new LinkBatch;
 296                         foreach ( $pages as $titleText => $options ) {
 297                                 $batch->addObj( Title::newFromText( $titleText ) );
 298                         }
 299
 300                         if ( !$batch->isEmpty() ) {
 301                                 $res = $dbr->select( [ 'page', 'revision' ],
 302                                         // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
 303                                         [ 'page_namespace', 'page_title', 'page_touched', 'rev_len', 'rev_sha1' ],
 304                                         $batch->constructSet( 'page', $dbr ),
 305                                         __METHOD__,
 306                                         [],
 307                                         [ 'revision' => [ 'INNER JOIN', [ 'page_latest=rev_id' ] ] ]
 308                                 );
 309                                 foreach ( $res as $row ) {
 310                                         // Avoid including ids or timestamps of revision/page tables so
 311                                         // that versions are not wasted
 312                                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 313                                         $this->titleInfo[$key][$title->getPrefixedText()] = [
 314                                                 'rev_len' => $row->rev_len,
 315                                                 'rev_sha1' => $row->rev_sha1,
 316                                                 'page_touched' => $row->page_touched,
 317                                         ];
 318                                 }
 319                         }
 320                 }
 321                 return $this->titleInfo[$key];
 322         }
 323
 324         public function getPosition() {
 325                 return $this->position;
 326         }
 327 }