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 /**
  24  * Abstraction for resource loader modules, with name registration and maxage functionality.
  25  */
  26 abstract class ResourceLoaderModule {
  27
  28         /* Protected Members */
  29
  30         protected $name = null;
  31
  32         // In-object cache for file dependencies
  33         protected $fileDeps = array();
  34         // In-object cache for message blob mtime
  35         protected $msgBlobMtime = array();
  36
  37         /* Methods */
  38
  39         /**
  40          * Get this module's name. This is set when the module is registered
  41          * with ResourceLoader::register()
  42          *
  43          * @return Mixed: Name (string) or null if no name was set
  44          */
  45         public function getName() {
  46                 return $this->name;
  47         }
  48
  49         /**
  50          * Set this module's name. This is called by ResourceLodaer::register()
  51          * when registering the module. Other code should not call this.
  52          *
  53          * @param $name String: Name
  54          */
  55         public function setName( $name ) {
  56                 $this->name = $name;
  57         }
  58
  59         /**
  60          * Get whether CSS for this module should be flipped
  61          */
  62         public function getFlip( $context ) {
  63                 return $context->getDirection() === 'rtl';
  64         }
  65
  66         /**
  67          * Get all JS for this module for a given language and skin.
  68          * Includes all relevant JS except loader scripts.
  69          *
  70          * @param $context ResourceLoaderContext: Context object
  71          * @return String: JavaScript code
  72          */
  73         public function getScript( ResourceLoaderContext $context ) {
  74                 // Stub, override expected
  75                 return '';
  76         }
  77
  78         /**
  79          * Get all CSS for this module for a given skin.
  80          *
  81          * @param $context ResourceLoaderContext: Context object
  82          * @return Array: List of CSS strings keyed by media type
  83          */
  84         public function getStyles( ResourceLoaderContext $context ) {
  85                 // Stub, override expected
  86                 return '';
  87         }
  88
  89         /**
  90          * Get the messages needed for this module.
  91          *
  92          * To get a JSON blob with messages, use MessageBlobStore::get()
  93          *
  94          * @return Array: List of message keys. Keys may occur more than once
  95          */
  96         public function getMessages() {
  97                 // Stub, override expected
  98                 return array();
  99         }
 100
 101         /**
 102          * Get the group this module is in.
 103          *
 104          * @return String: Group name
 105          */
 106         public function getGroup() {
 107                 // Stub, override expected
 108                 return null;
 109         }
 110
 111         /**
 112          * Get the loader JS for this module, if set.
 113          *
 114          * @return Mixed: JavaScript loader code as a string or boolean false if no custom loader set
 115          */
 116         public function getLoaderScript() {
 117                 // Stub, override expected
 118                 return false;
 119         }
 120
 121         /**
 122          * Get a list of modules this module depends on.
 123          *
 124          * Dependency information is taken into account when loading a module
 125          * on the client side. When adding a module on the server side,
 126          * dependency information is NOT taken into account and YOU are
 127          * responsible for adding dependent modules as well. If you don't do
 128          * this, the client side loader will send a second request back to the
 129          * server to fetch the missing modules, which kind of defeats the
 130          * purpose of the resource loader.
 131          *
 132          * To add dependencies dynamically on the client side, use a custom
 133          * loader script, see getLoaderScript()
 134          * @return Array: List of module names as strings
 135          */
 136         public function getDependencies() {
 137                 // Stub, override expected
 138                 return array();
 139         }
 140
 141         /**
 142          * Get the files this module depends on indirectly for a given skin.
 143          * Currently these are only image files referenced by the module's CSS.
 144          *
 145          * @param $skin String: Skin name
 146          * @return Array: List of files
 147          */
 148         public function getFileDependencies( $skin ) {
 149                 // Try in-object cache first
 150                 if ( isset( $this->fileDeps[$skin] ) ) {
 151                         return $this->fileDeps[$skin];
 152                 }
 153
 154                 $dbr = wfGetDB( DB_SLAVE );
 155                 $deps = $dbr->selectField( 'module_deps', 'md_deps', array(
 156                                 'md_module' => $this->getName(),
 157                                 'md_skin' => $skin,
 158                         ), __METHOD__
 159                 );
 160                 if ( !is_null( $deps ) ) {
 161                         $this->fileDeps[$skin] = (array) FormatJson::decode( $deps, true );
 162                 } else {
 163                         $this->fileDeps[$skin] = array();
 164                 }
 165                 return $this->fileDeps[$skin];
 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 Integer: 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 Integer: 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: Context object
 218          * @return Integer: UNIX timestamp
 219          */
 220         public function getModifiedTime( ResourceLoaderContext $context ) {
 221                 // 0 would mean now
 222                 return 1;
 223         }
 224 }