includes/resourceloader/ResourceLoaderModule.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @author Trevor Parscal
  20  * @author Roan Kattouw
  21  */
  22
  23 defined( 'MEDIAWIKI' ) || die( 1 );
  24
  25 /**
  26  * Abstraction for resource loader modules, with name registration and maxage functionality.
  27  */
  28 abstract class ResourceLoaderModule {
  29
  30         /* Protected Members */
  31
  32         protected $name = null;
  33
  34         // In-object cache for file dependencies
  35         protected $fileDeps = array();
  36         // In-object cache for message blob mtime
  37         protected $msgBlobMtime = array();
  38
  39         /* Methods */
  40
  41         /**
  42          * Get this module's name. This is set when the module is registered
  43          * with ResourceLoader::register()
  44          *
  45          * @return Mixed: name (string) or null if no name was set
  46          */
  47         public function getName() {
  48                 return $this->name;
  49         }
  50
  51         /**
  52          * Set this module's name. This is called by ResourceLodaer::register()
  53          * when registering the module. Other code should not call this.
  54          *
  55          * @param $name String: name
  56          */
  57         public function setName( $name ) {
  58                 $this->name = $name;
  59         }
  60
  61         /**
  62          * Get whether CSS for this module should be flipped
  63          */
  64         public function getFlip( $context ) {
  65                 return $context->getDirection() === 'rtl';
  66         }
  67
  68         /**
  69          * Get all JS for this module for a given language and skin.
  70          * Includes all relevant JS except loader scripts.
  71          *
  72          * @param $context ResourceLoaderContext object
  73          * @return String: JS
  74          */
  75         public function getScript( ResourceLoaderContext $context ) {
  76                 // Stub, override expected
  77                 return '';
  78         }
  79
  80         /**
  81          * Get all CSS for this module for a given skin.
  82          *
  83          * @param $context ResourceLoaderContext object
  84          * @return array: strings of CSS keyed by media type
  85          */
  86         public function getStyles( ResourceLoaderContext $context ) {
  87                 // Stub, override expected
  88                 return '';
  89         }
  90
  91         /**
  92          * Get the messages needed for this module.
  93          *
  94          * To get a JSON blob with messages, use MessageBlobStore::get()
  95          *
  96          * @return array of message keys. Keys may occur more than once
  97          */
  98         public function getMessages() {
  99                 // Stub, override expected
 100                 return array();
 101         }
 102
 103         /**
 104          * Get the group this module is in.
 105          *
 106          * @return string of group name
 107          */
 108         public function getGroup() {
 109                 // Stub, override expected
 110                 return null;
 111         }
 112
 113         /**
 114          * Get the loader JS for this module, if set.
 115          *
 116          * @return Mixed: loader JS (string) or false if no custom loader set
 117          */
 118         public function getLoaderScript() {
 119                 // Stub, override expected
 120                 return false;
 121         }
 122
 123         /**
 124          * Get a list of modules this module depends on.
 125          *
 126          * Dependency information is taken into account when loading a module
 127          * on the client side. When adding a module on the server side,
 128          * dependency information is NOT taken into account and YOU are
 129          * responsible for adding dependent modules as well. If you don't do
 130          * this, the client side loader will send a second request back to the
 131          * server to fetch the missing modules, which kind of defeats the
 132          * purpose of the resource loader.
 133          *
 134          * To add dependencies dynamically on the client side, use a custom
 135          * loader script, see getLoaderScript()
 136          * @return Array of module names (strings)
 137          */
 138         public function getDependencies() {
 139                 // Stub, override expected
 140                 return array();
 141         }
 142
 143         /**
 144          * Get the files this module depends on indirectly for a given skin.
 145          * Currently these are only image files referenced by the module's CSS.
 146          *
 147          * @param $skin String: skin name
 148          * @return array of files
 149          */
 150         public function getFileDependencies( $skin ) {
 151                 // Try in-object cache first
 152                 if ( isset( $this->fileDeps[$skin] ) ) {
 153                         return $this->fileDeps[$skin];
 154                 }
 155
 156                 $dbr = wfGetDB( DB_SLAVE );
 157                 $deps = $dbr->selectField( 'module_deps', 'md_deps', array(
 158                                 'md_module' => $this->getName(),
 159                                 'md_skin' => $skin,
 160                         ), __METHOD__
 161                 );
 162                 if ( !is_null( $deps ) ) {
 163                         return $this->fileDeps[$skin] = (array) FormatJson::decode( $deps, true );
 164                 }
 165                 return $this->fileDeps[$skin] = array();
 166         }
 167
 168         /**
 169          * Set preloaded file dependency information. Used so we can load this
 170          * information for all modules at once.
 171          * @param $skin string Skin name
 172          * @param $deps array Array of file names
 173          */
 174         public function setFileDependencies( $skin, $deps ) {
 175                 $this->fileDeps[$skin] = $deps;
 176         }
 177
 178         /**
 179          * Get the last modification timestamp of the message blob for this
 180          * module in a given language.
 181          * @param $lang string Language code
 182          * @return int UNIX timestamp, or 0 if no blob found
 183          */
 184         public function getMsgBlobMtime( $lang ) {
 185                 if ( !count( $this->getMessages() ) )
 186                         return 0;
 187
 188                 $dbr = wfGetDB( DB_SLAVE );
 189                 $msgBlobMtime = $dbr->selectField( 'msg_resource', 'mr_timestamp', array(
 190                                 'mr_resource' => $this->getName(),
 191                                 'mr_lang' => $lang
 192                         ), __METHOD__
 193                 );
 194                 $this->msgBlobMtime[$lang] = $msgBlobMtime ? wfTimestamp( TS_UNIX, $msgBlobMtime ) : 0;
 195                 return $this->msgBlobMtime[$lang];
 196         }
 197
 198         /**
 199          * Set a preloaded message blob last modification timestamp. Used so we
 200          * can load this information for all modules at once.
 201          * @param $lang string Language code
 202          * @param $mtime int UNIX timestamp or 0 if there is no such blob
 203          */
 204         public function setMsgBlobMtime( $lang, $mtime ) {
 205                 $this->msgBlobMtime[$lang] = $mtime;
 206         }
 207
 208         /* Abstract Methods */
 209
 210         /**
 211          * Get this module's last modification timestamp for a given
 212          * combination of language, skin and debug mode flag. This is typically
 213          * the highest of each of the relevant components' modification
 214          * timestamps. Whenever anything happens that changes the module's
 215          * contents for these parameters, the mtime should increase.
 216          *
 217          * @param $context ResourceLoaderContext object
 218          * @return int UNIX timestamp
 219          */
 220         public function getModifiedTime( ResourceLoaderContext $context ) {
 221                 // 0 would mean now
 222                 return 1;
 223         }
 224 }