resources/mediawiki/mediawiki.inspect.js

   1 /*!
   2  * Tools for inspecting page composition and performance.
   3  *
   4  * @author Ori Livneh
   5  * @since 1.22
   6  */
   7 ( function ( mw, $ ) {
   8
   9         /**
  10          * @class mw.inspect
  11          * @singleton
  12          */
  13         var inspect = {
  14
  15                 /**
  16                  * Calculate the byte size of a ResourceLoader module.
  17                  *
  18                  * @param {string} moduleName The name of the module
  19                  * @return {number|null} Module size in bytes or null
  20                  */
  21                 getModuleSize: function ( moduleName ) {
  22                         var module = mw.loader.moduleRegistry[ moduleName ],
  23                                 payload = 0;
  24
  25                         if ( mw.loader.getState( moduleName ) !== 'ready' ) {
  26                                 return null;
  27                         }
  28
  29                         if ( !module.style && !module.script ) {
  30                                 return null;
  31                         }
  32
  33                         // Tally CSS
  34                         if ( module.style && $.isArray( module.style.css ) ) {
  35                                 $.each( module.style.css, function ( i, stylesheet ) {
  36                                         payload += $.byteLength( stylesheet );
  37                                 } );
  38                         }
  39
  40                         // Tally JavaScript
  41                         if ( $.isFunction( module.script ) ) {
  42                                 payload += $.byteLength( module.script.toString() );
  43                         }
  44
  45                         return payload;
  46                 },
  47
  48                 /**
  49                  * Get a list of all loaded ResourceLoader modules.
  50                  *
  51                  * @return {Array} List of module names
  52                  */
  53                 getLoadedModules: function () {
  54                         return $.grep( mw.loader.getModuleNames(), function ( module ) {
  55                                 return mw.loader.getState( module ) === 'ready';
  56                         } );
  57                 },
  58
  59                 /**
  60                  * Print a breakdown of all loaded modules and their size in kilobytes
  61                  * to the debug console. Modules are ordered from largest to smallest.
  62                  */
  63                 inspectModules: function () {
  64                         var console = window.console;
  65
  66                         $( function () {
  67                                 // Map each module to a descriptor object.
  68                                 var modules = $.map( inspect.getLoadedModules(), function ( module ) {
  69                                         return {
  70                                                 name: module,
  71                                                 size: inspect.getModuleSize( module )
  72                                         };
  73                                 } );
  74
  75                                 // Sort module descriptors by size, largest first.
  76                                 modules.sort( function ( a, b ) {
  77                                         return b.size - a.size;
  78                                 } );
  79
  80                                 // Convert size to human-readable string.
  81                                 $.each( modules, function ( i, module ) {
  82                                         module.size = module.size > 1024 ?
  83                                                 ( module.size / 1024 ).toFixed( 2 ) + ' KB' :
  84                                                 ( module.size !== null ? module.size + ' B' : null );
  85                                 } );
  86
  87                                 if ( console ) {
  88                                         if ( console.table ) {
  89                                                 console.table( modules );
  90                                         } else {
  91                                                 $.each( modules, function ( i, module ) {
  92                                                         console.log( [ module.name, module.size ].join( '\t' ) );
  93                                                 } );
  94                                         }
  95                                 }
  96                         } );
  97                 }
  98         };
  99
 100         if ( mw.config.get( 'debug' ) ) {
 101                 inspect.getModuleSize = function () { return null; };
 102                 mw.log( 'mw.inspect: Module sizes are not available in debug mode.' );
 103         }
 104
 105         mw.inspect = inspect;
 106
 107 }( mediaWiki, jQuery ) );