2 * Base library for MediaWiki.
4 * Exposed globally as `mw`, with `mediaWiki` as alias.
7 * @alternateClassName mediaWiki
10 /* global $VARS, $CODE */
15 var mw
, StringSet
, log
,
16 hasOwn
= Object
.prototype.hasOwnProperty
,
20 * FNV132 hash function
22 * This function implements the 32-bit version of FNV-1.
23 * It is equivalent to hash( 'fnv132', ... ) in PHP, except
24 * its output is base 36 rather than hex.
25 * See <https://en.wikipedia.org/wiki/FNV_hash_function>
28 * @param {string} str String to hash
29 * @return {string} hash as an seven-character base 36 string
31 function fnv132( str
) {
32 /* eslint-disable no-bitwise */
33 var hash
= 0x811C9DC5,
36 for ( i
= 0; i
< str
.length
; i
++ ) {
37 hash
+= ( hash
<< 1 ) + ( hash
<< 4 ) + ( hash
<< 7 ) + ( hash
<< 8 ) + ( hash
<< 24 );
38 hash
^= str
.charCodeAt( i
);
41 hash
= ( hash
>>> 0 ).toString( 36 );
42 while ( hash
.length
< 7 ) {
47 /* eslint-enable no-bitwise */
50 function defineFallbacks() {
51 // <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set>
52 StringSet
= window
.Set
|| ( function () {
57 function StringSet() {
58 this.set = Object
.create( null );
60 StringSet
.prototype.add = function ( value
) {
61 this.set[ value
] = true;
63 StringSet
.prototype.has = function ( value
) {
64 return value
in this.set;
71 * Alias property to the global object.
78 * @param {Mixed} value
80 function setGlobalMapValue( map
, key
, value
) {
81 map
.values
[ key
] = value
;
86 // Deprecation notice for mw.config globals (T58550, T72470)
87 map
=== mw
.config
&& 'Use mw.config instead.'
92 * Log a message to window.console, if possible.
94 * Useful to force logging of some errors that are otherwise hard to detect (i.e., this logs
95 * also in production mode). Gets console references in each invocation instead of caching the
96 * reference, so that debugging tools loaded later are supported (e.g. Firebug Lite in IE).
99 * @param {string} topic Stream name passed by mw.track
100 * @param {Object} data Data passed by mw.track
101 * @param {Error} [data.exception]
102 * @param {string} data.source Error source
103 * @param {string} [data.module] Name of module which caused the error
105 function logError( topic
, data
) {
106 /* eslint-disable no-console */
109 source
= data
.source
,
110 module
= data
.module
,
111 console
= window
.console
;
113 if ( console
&& console
.log
) {
114 msg
= ( e
? 'Exception' : 'Error' ) + ' in ' + source
;
116 msg
+= ' in module ' + module
;
118 msg
+= ( e
? ':' : '.' );
121 // If we have an exception object, log it to the warning channel to trigger
122 // proper stacktraces in browsers that support it.
123 if ( e
&& console
.warn
) {
127 /* eslint-enable no-console */
131 * Create an object that can be read from or written to via methods that allow
132 * interaction both with single and multiple properties at once.
138 * @param {boolean} [global=false] Whether to synchronise =values to the global
139 * window object (for backwards-compatibility with mw.config; T72470). Values are
140 * copied in one direction only. Changes to globals do not reflect in the map.
142 function Map( global
) {
143 this.values
= Object
.create( null );
144 if ( global
=== true ) {
145 // Override #set to also set the global variable
146 this.set = function ( selection
, value
) {
148 if ( arguments
.length
> 1 ) {
149 if ( typeof selection
!== 'string' ) {
152 setGlobalMapValue( this, selection
, value
);
155 if ( typeof selection
=== 'object' ) {
156 for ( s
in selection
) {
157 setGlobalMapValue( this, s
, selection
[ s
] );
170 * Get the value of one or more keys.
172 * If called with no arguments, all values are returned.
174 * @param {string|Array} [selection] Key or array of keys to retrieve values for.
175 * @param {Mixed} [fallback=null] Value for keys that don't exist.
176 * @return {Mixed|Object|null} If selection was a string, returns the value,
177 * If selection was an array, returns an object of key/values.
178 * If no selection is passed, a new object with all key/values is returned.
180 get: function ( selection
, fallback
) {
182 fallback
= arguments
.length
> 1 ? fallback
: null;
184 if ( Array
.isArray( selection
) ) {
186 for ( i
= 0; i
< selection
.length
; i
++ ) {
187 if ( typeof selection
[ i
] === 'string' ) {
188 results
[ selection
[ i
] ] = selection
[ i
] in this.values
?
189 this.values
[ selection
[ i
] ] :
196 if ( typeof selection
=== 'string' ) {
197 return selection
in this.values
?
198 this.values
[ selection
] :
202 if ( selection
=== undefined ) {
204 for ( i
in this.values
) {
205 results
[ i
] = this.values
[ i
];
210 // Invalid selection key
215 * Set one or more key/value pairs.
217 * @param {string|Object} selection Key to set value for, or object mapping keys to values
218 * @param {Mixed} [value] Value to set (optional, only in use when key is a string)
219 * @return {boolean} True on success, false on failure
221 set: function ( selection
, value
) {
223 // Use `arguments.length` because `undefined` is also a valid value.
224 if ( arguments
.length
> 1 ) {
225 if ( typeof selection
!== 'string' ) {
228 this.values
[ selection
] = value
;
231 if ( typeof selection
=== 'object' ) {
232 for ( s
in selection
) {
233 this.values
[ s
] = selection
[ s
];
241 * Check if one or more keys exist.
243 * @param {Mixed} selection Key or array of keys to check
244 * @return {boolean} True if the key(s) exist
246 exists: function ( selection
) {
248 if ( Array
.isArray( selection
) ) {
249 for ( i
= 0; i
< selection
.length
; i
++ ) {
250 if ( typeof selection
[ i
] !== 'string' || !( selection
[ i
] in this.values
) ) {
256 return typeof selection
=== 'string' && selection
in this.values
;
262 /* eslint-disable no-console */
263 log
= ( function () {
265 * Write a verbose message to the browser's console in debug mode.
267 * This method is mainly intended for verbose logging. It is a no-op in production mode.
268 * In ResourceLoader debug mode, it will use the browser's console if available, with
269 * fallback to creating a console interface in the DOM and logging messages there.
271 * See {@link mw.log} for other logging methods.
274 * @param {...string} msg Messages to output to console.
276 var log = function () {},
277 console
= window
.console
;
279 // Note: Keep list of methods in sync with restoration in mediawiki.log.js
280 // when adding or removing mw.log methods below!
283 * Collection of methods to help log messages to the console.
290 * Write a message to the browser console's warning channel.
292 * This method is a no-op in browsers that don't implement the Console API.
294 * @param {...string} msg Messages to output to console
296 log
.warn
= console
&& console
.warn
&& Function
.prototype.bind
?
297 Function
.prototype.bind
.call( console
.warn
, console
) :
301 * Write a message to the browser console's error channel.
303 * Most browsers also print a stacktrace when calling this method if the
304 * argument is an Error object.
306 * This method is a no-op in browsers that don't implement the Console API.
309 * @param {...Mixed} msg Messages to output to console
311 log
.error
= console
&& console
.error
&& Function
.prototype.bind
?
312 Function
.prototype.bind
.call( console
.error
, console
) :
316 * Create a property on a host object that, when accessed, will produce
317 * a deprecation warning in the console.
319 * @param {Object} obj Host object of deprecated property
320 * @param {string} key Name of property to create in `obj`
321 * @param {Mixed} val The value this property should return when accessed
322 * @param {string} [msg] Optional text to include in the deprecation message
323 * @param {string} [logName=key] Optional custom name for the feature.
324 * This is used instead of `key` in the message and `mw.deprecate` tracking.
326 log
.deprecate
= !Object
.defineProperty
? function ( obj
, key
, val
) {
328 } : function ( obj
, key
, val
, msg
, logName
) {
330 function maybeLog() {
332 trace
= new Error().stack
;
334 stacks
= new StringSet();
336 if ( !stacks
.has( trace
) ) {
338 name
= logName
|| key
;
339 mw
.track( 'mw.deprecate', name
);
341 'Use of "' + name
+ '" is deprecated.' + ( msg
? ( ' ' + msg
) : '' )
345 // Support: Safari 5.0
346 // Throws "not supported on DOM Objects" for Node or Element objects (incl. document)
347 // Safari 4.0 doesn't have this method, and it was fixed in Safari 5.1.
349 Object
.defineProperty( obj
, key
, {
356 set: function ( newVal
) {
368 /* eslint-enable no-console */
374 redefineFallbacksForTest: function () {
375 if ( !window
.QUnit
) {
376 throw new Error( 'Reset not allowed outside unit tests' );
382 * Get the current time, measured in milliseconds since January 1, 1970 (UTC).
384 * On browsers that implement the Navigation Timing API, this function will produce
385 * floating-point values with microsecond precision that are guaranteed to be monotonic.
386 * On all other browsers, it will fall back to using `Date`.
388 * @return {number} Current time
391 // Optimisation: Define the shortcut on first call, not at module definition.
392 var perf
= window
.performance
,
393 navStart
= perf
&& perf
.timing
&& perf
.timing
.navigationStart
;
395 // Define the relevant shortcut
396 mw
.now
= navStart
&& typeof perf
.now
=== 'function' ?
397 function () { return navStart
+ perf
.now(); } :
404 * List of all analytic events emitted so far.
409 trackQueue
: trackQueue
,
411 track: function ( topic
, data
) {
412 trackQueue
.push( { topic
: topic
, timeStamp
: mw
.now(), data
: data
} );
413 // The base module extends this method to fire events here
417 * Track an early error event via mw.track and send it to the window console.
420 * @param {string} topic Topic name
421 * @param {Object} data Data describing the event, encoded as an object; see mw#logError
423 trackError: function ( topic
, data
) {
424 mw
.track( topic
, data
);
425 logError( topic
, data
);
428 // Expose Map constructor
432 * Map of configuration values.
434 * Check out [the complete list of configuration values](https://www.mediawiki.org/wiki/Manual:Interface/JavaScript#mw.config)
437 * If `$wgLegacyJavaScriptGlobals` is true, this Map will add its values to the
438 * global `window` object.
440 * @property {mw.Map} config
442 // Dummy placeholder later assigned in ResourceLoaderStartUpModule
446 * Empty object for third-party libraries, for cases where you don't
447 * want to add a new global, or the global is bad and needs containment
455 * Access container for deprecated functionality that can be moved from
456 * from their legacy location and attached to this object (e.g. a global
457 * function that is deprecated and as stop-gap can be exposed through here).
459 * This was reserved for future use but never ended up being used.
461 * @deprecated since 1.22 Let deprecated identifiers keep their original name
462 * and use mw.log#deprecate to create an access container for tracking.
468 * Store for messages.
475 * Store for templates associated with a module.
479 templates
: new Map(),
485 * Client for ResourceLoader server end point.
487 * This client is in charge of maintaining the module registry and state
488 * machine, initiating network (batch) requests for loading modules, as
489 * well as dependency resolution and execution of source code.
491 * For more information, refer to
492 * <https://www.mediawiki.org/wiki/ResourceLoader/Features>
497 loader
: ( function () {
500 * Fired via mw.track on various resource loading errors.
502 * @event resourceloader_exception
503 * @param {Error|Mixed} e The error that was thrown. Almost always an Error
504 * object, but in theory module code could manually throw something else, and that
505 * might also end up here.
506 * @param {string} [module] Name of the module which caused the error. Omitted if the
507 * error is not module-related or the module cannot be easily identified due to
509 * @param {string} source Source of the error. Possible values:
511 * - style: stylesheet error (only affects old IE where a special style loading method
513 * - load-callback: exception thrown by user callback
514 * - module-execute: exception thrown by module code
515 * - resolve: failed to sort dependencies for a module in mw.loader.load
516 * - store-eval: could not evaluate module code cached in localStorage
517 * - store-localstorage-init: localStorage or JSON parse error in mw.loader.store.init
518 * - store-localstorage-json: JSON conversion error in mw.loader.store
519 * - store-localstorage-update: localStorage conversion error in mw.loader.store.
523 * Fired via mw.track on resource loading error conditions.
525 * @event resourceloader_assert
526 * @param {string} source Source of the error. Possible values:
528 * - bug-T59567: failed to cache script due to an Opera function -> string conversion
529 * bug; see <https://phabricator.wikimedia.org/T59567> for details
533 * Mapping of registered modules.
535 * See #implement and #execute for exact details on support for script, style and messages.
541 * // From mw.loader.register()
542 * 'version': '########' (hash)
543 * 'dependencies': ['required.foo', 'bar.also', ...]
544 * 'group': 'somegroup', (or) null
545 * 'source': 'local', (or) 'anotherwiki'
546 * 'skip': 'return !!window.Example', (or) null
547 * 'module': export Object
549 * // Set from execute() or mw.loader.state()
550 * 'state': 'registered', 'loaded', 'loading', 'ready', 'error', or 'missing'
552 * // Optionally added at run-time by mw.loader.implement()
554 * 'script': closure, array of urls, or string
555 * 'style': { ... } (see #execute)
556 * 'messages': { 'key': 'value', ... }
563 * The module is known to the system but not yet required.
564 * Meta data is registered via mw.loader#register. Calls to that method are
565 * generated server-side by the startup module.
567 * The module was required through mw.loader (either directly or as dependency of
568 * another module). The client will fetch module contents from the server.
569 * The contents are then stashed in the registry via mw.loader#implement.
571 * The module has been loaded from the server and stashed via mw.loader#implement.
572 * If the module has no more dependencies in-flight, the module will be executed
573 * immediately. Otherwise execution is deferred, controlled via #handlePending.
575 * The module is being executed.
577 * The module has been successfully executed.
579 * The module (or one of its dependencies) produced an error during execution.
581 * The module was registered client-side and requested, but the server denied knowledge
582 * of the module's existence.
588 // Mapping of sources, keyed by source-id, values are strings.
593 // 'sourceId': 'http://example.org/w/load.php'
598 // For queueModuleScript()
599 handlingPendingRequests
= false,
600 pendingRequests
= [],
602 // List of modules to be loaded
606 * List of callback jobs waiting for modules to be ready.
608 * Jobs are created by #enqueue() and run by #handlePending().
610 * Typically when a job is created for a module, the job's dependencies contain
611 * both the required module and all its recursive dependencies.
616 * 'dependencies': [ module names ],
617 * 'ready': Function callback
618 * 'error': Function callback
621 * @property {Object[]} jobs
628 * @property {Array} baseModules
630 baseModules
= $VARS
.baseModules
,
633 * For #addEmbeddedCSS() and #addLink()
636 * @property {HTMLElement|null} marker
638 marker
= document
.querySelector( 'meta[name="ResourceLoaderDynamicStyles"]' ),
640 // For #addEmbeddedCSS()
642 rAF
= window
.requestAnimationFrame
|| setTimeout
;
645 * Create a new style element and add it to the DOM.
648 * @param {string} text CSS text
649 * @param {Node|null} [nextNode] The element where the style tag
650 * should be inserted before
651 * @return {HTMLElement} Reference to the created style element
653 function newStyleTag( text
, nextNode
) {
654 var el
= document
.createElement( 'style' );
655 el
.appendChild( document
.createTextNode( text
) );
656 if ( nextNode
&& nextNode
.parentNode
) {
657 nextNode
.parentNode
.insertBefore( el
, nextNode
);
659 document
.head
.appendChild( el
);
666 * @param {Object} cssBuffer
668 function flushCssBuffer( cssBuffer
) {
670 // Mark this object as inactive now so that further calls to addEmbeddedCSS() from
671 // the callbacks go to a new buffer instead of this one (T105973)
672 cssBuffer
.active
= false;
673 newStyleTag( cssBuffer
.cssText
, marker
);
674 for ( i
= 0; i
< cssBuffer
.callbacks
.length
; i
++ ) {
675 cssBuffer
.callbacks
[ i
]();
680 * Add a bit of CSS text to the current browser page.
682 * The creation and insertion of the `<style>` element is debounced for two reasons:
684 * - Performing the insertion before the next paint round via requestAnimationFrame
685 * avoids forced or wasted style recomputations, which are expensive in browsers.
686 * - Reduce how often new stylesheets are inserted by letting additional calls to this
687 * function accumulate into a buffer for at least one JavaScript tick. Modules are
688 * received from the server in batches, which means there is likely going to be many
689 * calls to this function in a row within the same tick / the same call stack.
693 * @param {string} cssText CSS text to be added in a `<style>` tag.
694 * @param {Function} callback Called after the insertion has occurred
696 function addEmbeddedCSS( cssText
, callback
) {
697 // Create a buffer if:
698 // - We don't have one yet.
699 // - The previous one is closed.
700 // - The next CSS chunk syntactically needs to be at the start of a stylesheet (T37562).
701 if ( !nextCssBuffer
|| nextCssBuffer
.active
=== false || cssText
.slice( 0, '@import'.length
) === '@import' ) {
709 // Linebreak for somewhat distinguishable sections
710 nextCssBuffer
.cssText
+= '\n' + cssText
;
711 nextCssBuffer
.callbacks
.push( callback
);
713 if ( nextCssBuffer
.active
=== null ) {
714 nextCssBuffer
.active
= true;
715 // The flushCssBuffer callback has its parameter bound by reference, which means
716 // 1) We can still extend the buffer from our object reference after this point.
717 // 2) We can safely re-assign the variable (not the object) to start a new buffer.
718 rAF( flushCssBuffer
.bind( null, nextCssBuffer
) );
724 * @param {Array} modules List of module names
725 * @return {string} Hash of concatenated version hashes.
727 function getCombinedVersion( modules
) {
728 var hashes
= modules
.reduce( function ( result
, module
) {
729 return result
+ registry
[ module
].version
;
731 return fnv132( hashes
);
735 * Determine whether all dependencies are in state 'ready', which means we may
736 * execute the module or job now.
739 * @param {Array} modules Names of modules to be checked
740 * @return {boolean} True if all modules are in state 'ready', false otherwise
742 function allReady( modules
) {
744 for ( i
= 0; i
< modules
.length
; i
++ ) {
745 if ( mw
.loader
.getState( modules
[ i
] ) !== 'ready' ) {
753 * Determine whether all direct and base dependencies are in state 'ready'
756 * @param {string} module Name of the module to be checked
757 * @return {boolean} True if all direct/base dependencies are in state 'ready'; false otherwise
759 function allWithImplicitReady( module
) {
760 return allReady( registry
[ module
].dependencies
) &&
761 ( baseModules
.indexOf( module
) !== -1 || allReady( baseModules
) );
765 * Determine whether all dependencies are in state 'ready', which means we may
766 * execute the module or job now.
769 * @param {Array} modules Names of modules to be checked
770 * @return {boolean} True if no modules are in state 'error' or 'missing', false otherwise
772 function anyFailed( modules
) {
774 for ( i
= 0; i
< modules
.length
; i
++ ) {
775 state
= mw
.loader
.getState( modules
[ i
] );
776 if ( state
=== 'error' || state
=== 'missing' ) {
784 * A module has entered state 'ready', 'error', or 'missing'. Automatically update
785 * pending jobs and modules that depend upon this module. If the given module failed,
786 * propagate the 'error' state up the dependency tree. Otherwise, go ahead and execute
787 * all jobs/modules now having their dependencies satisfied.
789 * Jobs that depend on a failed module, will have their error callback ran (if any).
792 * @param {string} module Name of module that entered one of the states 'ready', 'error', or 'missing'.
794 function handlePending( module
) {
795 var j
, job
, hasErrors
, m
, stateChange
, fromBaseModule
;
797 if ( registry
[ module
].state
=== 'error' || registry
[ module
].state
=== 'missing' ) {
798 fromBaseModule
= baseModules
.indexOf( module
) !== -1;
799 // If the current module failed, mark all dependent modules also as failed.
800 // Iterate until steady-state to propagate the error state upwards in the
804 for ( m
in registry
) {
805 if ( registry
[ m
].state
!== 'error' && registry
[ m
].state
!== 'missing' ) {
806 // Always propagate errors from base modules to regular modules (implicit dependency).
807 // Between base modules or regular modules, consider direct dependencies only.
809 ( fromBaseModule
&& baseModules
.indexOf( m
) === -1 ) ||
810 anyFailed( registry
[ m
].dependencies
)
812 registry
[ m
].state
= 'error';
817 } while ( stateChange
);
820 // Execute all jobs whose dependencies are either all satisfied or contain at least one failed module.
821 for ( j
= 0; j
< jobs
.length
; j
++ ) {
822 hasErrors
= anyFailed( jobs
[ j
].dependencies
);
823 if ( hasErrors
|| allReady( jobs
[ j
].dependencies
) ) {
824 // All dependencies satisfied, or some have errors
830 if ( typeof job
.error
=== 'function' ) {
831 job
.error( new Error( 'Module ' + module
+ ' has failed dependencies' ), [ module
] );
834 if ( typeof job
.ready
=== 'function' ) {
839 // A user-defined callback raised an exception.
840 // Swallow it to protect our state machine!
841 mw
.trackError( 'resourceloader.exception', {
844 source
: 'load-callback'
850 // The current module became 'ready'.
851 if ( registry
[ module
].state
=== 'ready' ) {
852 // Queue it for later syncing to the module store.
853 mw
.loader
.store
.add( module
);
854 // Recursively execute all dependent modules that were already loaded
855 // (waiting for execution) and no longer have unsatisfied dependencies.
856 for ( m
in registry
) {
857 // Base modules may have dependencies amongst eachother to ensure correct
858 // execution order. Regular modules wait for all base modules.
859 if ( registry
[ m
].state
=== 'loaded' && allWithImplicitReady( m
) ) {
860 // eslint-disable-next-line no-use-before-define
868 * Resolve dependencies and detect circular references.
871 * @param {string} module Name of the top-level module whose dependencies shall be
872 * resolved and sorted.
873 * @param {Array} resolved Returns a topological sort of the given module and its
874 * dependencies, such that later modules depend on earlier modules. The array
875 * contains the module names. If the array contains already some module names,
876 * this function appends its result to the pre-existing array.
877 * @param {StringSet} [unresolved] Used to track the current dependency
878 * chain, and to report loops in the dependency graph.
879 * @throws {Error} If any unregistered module or a dependency loop is encountered
881 function sortDependencies( module
, resolved
, unresolved
) {
884 if ( !hasOwn
.call( registry
, module
) ) {
885 throw new Error( 'Unknown dependency: ' + module
);
888 if ( registry
[ module
].skip
!== null ) {
889 // eslint-disable-next-line no-new-func
890 skip
= new Function( registry
[ module
].skip
);
891 registry
[ module
].skip
= null;
893 registry
[ module
].skipped
= true;
894 registry
[ module
].dependencies
= [];
895 registry
[ module
].state
= 'ready';
896 handlePending( module
);
901 if ( resolved
.indexOf( module
) !== -1 ) {
902 // Module already resolved; nothing to do
905 // Create unresolved if not passed in
907 unresolved
= new StringSet();
911 if ( baseModules
.indexOf( module
) === -1 ) {
912 baseModules
.forEach( function ( baseModule
) {
913 if ( resolved
.indexOf( baseModule
) === -1 ) {
914 resolved
.push( baseModule
);
919 // Tracks down dependencies
920 deps
= registry
[ module
].dependencies
;
921 unresolved
.add( module
);
922 for ( i
= 0; i
< deps
.length
; i
++ ) {
923 if ( resolved
.indexOf( deps
[ i
] ) === -1 ) {
924 if ( unresolved
.has( deps
[ i
] ) ) {
926 'Circular reference detected: ' + module
+ ' -> ' + deps
[ i
]
930 sortDependencies( deps
[ i
], resolved
, unresolved
);
933 resolved
.push( module
);
937 * Get names of module that a module depends on, in their proper dependency order.
940 * @param {string[]} modules Array of string module names
941 * @return {Array} List of dependencies, including 'module'.
942 * @throws {Error} If an unregistered module or a dependency loop is encountered
944 function resolve( modules
) {
945 var i
, resolved
= [];
946 for ( i
= 0; i
< modules
.length
; i
++ ) {
947 sortDependencies( modules
[ i
], resolved
);
953 * Like #resolve(), except it will silently ignore modules that
954 * are missing or have missing dependencies.
957 * @param {string[]} modules Array of string module names
958 * @return {Array} List of dependencies.
960 function resolveStubbornly( modules
) {
961 var i
, saved
, resolved
= [];
962 for ( i
= 0; i
< modules
.length
; i
++ ) {
963 saved
= resolved
.slice();
965 sortDependencies( modules
[ i
], resolved
);
967 // This module is unknown or has unknown dependencies.
968 // Undo any incomplete resolutions made and keep going.
970 mw
.trackError( 'resourceloader.exception', {
980 * Load and execute a script.
983 * @param {string} src URL to script, will be used as the src attribute in the script tag
984 * @param {Function} [callback] Callback to run after request resolution
986 function addScript( src
, callback
) {
987 var script
= document
.createElement( 'script' );
989 script
.onload
= script
.onerror = function () {
990 if ( script
.parentNode
) {
991 script
.parentNode
.removeChild( script
);
999 document
.head
.appendChild( script
);
1003 * Queue the loading and execution of a script for a particular module.
1005 * This does for debug mode what runScript() does for production.
1008 * @param {string} src URL of the script
1009 * @param {string} moduleName Name of currently executing module
1010 * @param {Function} callback Callback to run after addScript() resolution
1012 function queueModuleScript( src
, moduleName
, callback
) {
1013 pendingRequests
.push( function () {
1014 // Keep in sync with execute()/runScript().
1015 if ( moduleName
!== 'jquery' && hasOwn
.call( registry
, moduleName
) ) {
1016 window
.require
= mw
.loader
.require
;
1017 window
.module
= registry
[ moduleName
].module
;
1019 addScript( src
, function () {
1020 // 'module.exports' should not persist after the file is executed to
1021 // avoid leakage to unrelated code. 'require' should be kept, however,
1022 // as asynchronous access to 'require' is allowed and expected. (T144879)
1023 delete window
.module
;
1025 // Start the next one (if any)
1026 if ( pendingRequests
[ 0 ] ) {
1027 pendingRequests
.shift()();
1029 handlingPendingRequests
= false;
1033 if ( !handlingPendingRequests
&& pendingRequests
[ 0 ] ) {
1034 handlingPendingRequests
= true;
1035 pendingRequests
.shift()();
1040 * Utility function for execute()
1043 * @param {string} [media] Media attribute
1044 * @param {string} url URL
1046 function addLink( media
, url
) {
1047 var el
= document
.createElement( 'link' );
1049 el
.rel
= 'stylesheet';
1050 if ( media
&& media
!== 'all' ) {
1053 // If you end up here from an IE exception "SCRIPT: Invalid property value.",
1054 // see #addEmbeddedCSS, T33676, T43331, and T49277 for details.
1057 if ( marker
&& marker
.parentNode
) {
1058 marker
.parentNode
.insertBefore( el
, marker
);
1060 document
.head
.appendChild( el
);
1066 * @param {string} code JavaScript code
1068 function domEval( code
) {
1069 var script
= document
.createElement( 'script' );
1070 if ( mw
.config
.get( 'wgCSPNonce' ) !== false ) {
1071 script
.nonce
= mw
.config
.get( 'wgCSPNonce' );
1074 document
.head
.appendChild( script
);
1075 script
.parentNode
.removeChild( script
);
1079 * Add one or more modules to the module load queue.
1084 * @param {string[]} dependencies Array of module names in the registry
1085 * @param {Function} [ready] Callback to execute when all dependencies are ready
1086 * @param {Function} [error] Callback to execute when any dependency fails
1088 function enqueue( dependencies
, ready
, error
) {
1089 if ( allReady( dependencies
) ) {
1090 // Run ready immediately
1091 if ( ready
!== undefined ) {
1097 if ( anyFailed( dependencies
) ) {
1098 if ( error
!== undefined ) {
1099 // Execute error immediately if any dependencies have errors
1101 new Error( 'One or more dependencies failed to load' ),
1108 // Not all dependencies are ready, add to the load queue...
1110 // Add ready and error callbacks if they were given
1111 if ( ready
!== undefined || error
!== undefined ) {
1113 // Narrow down the list to modules that are worth waiting for
1114 dependencies
: dependencies
.filter( function ( module
) {
1115 var state
= registry
[ module
].state
;
1116 return state
=== 'registered' || state
=== 'loaded' || state
=== 'loading' || state
=== 'executing';
1123 dependencies
.forEach( function ( module
) {
1124 // Only queue modules that are still in the initial 'registered' state
1125 // (not ones already loading, ready or error).
1126 if ( registry
[ module
].state
=== 'registered' && queue
.indexOf( module
) === -1 ) {
1127 // Private modules must be embedded in the page. Don't bother queuing
1128 // these as the server will deny them anyway (T101806).
1129 if ( registry
[ module
].group
=== 'private' ) {
1130 registry
[ module
].state
= 'error';
1131 handlePending( module
);
1134 queue
.push( module
);
1142 * Executes a loaded module, making it ready to use
1145 * @param {string} module Module name to execute
1147 function execute( module
) {
1148 var key
, value
, media
, i
, urls
, cssHandle
, siteDeps
, siteDepErr
, runScript
,
1151 if ( !hasOwn
.call( registry
, module
) ) {
1152 throw new Error( 'Module has not been registered yet: ' + module
);
1154 if ( registry
[ module
].state
!== 'loaded' ) {
1155 throw new Error( 'Module in state "' + registry
[ module
].state
+ '" may not be executed: ' + module
);
1158 registry
[ module
].state
= 'executing';
1159 $CODE
.profileExecuteStart();
1161 runScript = function () {
1162 var script
, markModuleReady
, nestedAddScript
;
1164 $CODE
.profileScriptStart();
1165 script
= registry
[ module
].script
;
1166 markModuleReady = function () {
1167 $CODE
.profileScriptEnd();
1168 registry
[ module
].state
= 'ready';
1169 handlePending( module
);
1171 nestedAddScript = function ( arr
, callback
, i
) {
1172 // Recursively call queueModuleScript() in its own callback
1173 // for each element of arr.
1174 if ( i
>= arr
.length
) {
1175 // We're at the end of the array
1180 queueModuleScript( arr
[ i
], module
, function () {
1181 nestedAddScript( arr
, callback
, i
+ 1 );
1186 if ( Array
.isArray( script
) ) {
1187 nestedAddScript( script
, markModuleReady
, 0 );
1188 } else if ( typeof script
=== 'function' ) {
1189 // Keep in sync with queueModuleScript() for debug mode
1190 if ( module
=== 'jquery' ) {
1191 // This is a special case for when 'jquery' itself is being loaded.
1192 // - The standard jquery.js distribution does not set `window.jQuery`
1193 // in CommonJS-compatible environments (Node.js, AMD, RequireJS, etc.).
1194 // - MediaWiki's 'jquery' module also bundles jquery.migrate.js, which
1195 // in a CommonJS-compatible environment, will use require('jquery'),
1196 // but that can't work when we're still inside that module.
1199 // Pass jQuery twice so that the signature of the closure which wraps
1200 // the script can bind both '$' and 'jQuery'.
1201 script( window
.$, window
.$, mw
.loader
.require
, registry
[ module
].module
);
1205 } else if ( typeof script
=== 'string' ) {
1206 // Site and user modules are legacy scripts that run in the global scope.
1207 // This is transported as a string instead of a function to avoid needing
1208 // to use string manipulation to undo the function wrapper.
1213 // Module without script
1217 // Use mw.track instead of mw.log because these errors are common in production mode
1218 // (e.g. undefined variable), and mw.log is only enabled in debug mode.
1219 registry
[ module
].state
= 'error';
1220 $CODE
.profileScriptEnd();
1221 mw
.trackError( 'resourceloader.exception', {
1222 exception
: e
, module
:
1223 module
, source
: 'module-execute'
1225 handlePending( module
);
1229 // Add localizations to message system
1230 if ( registry
[ module
].messages
) {
1231 mw
.messages
.set( registry
[ module
].messages
);
1234 // Initialise templates
1235 if ( registry
[ module
].templates
) {
1236 mw
.templates
.set( module
, registry
[ module
].templates
);
1239 // Adding of stylesheets is asynchronous via addEmbeddedCSS().
1240 // The below function uses a counting semaphore to make sure we don't call
1241 // runScript() until after this module's stylesheets have been inserted
1243 cssHandle = function () {
1244 // Increase semaphore, when creating a callback for addEmbeddedCSS.
1246 return function () {
1248 // Decrease semaphore, when said callback is invoked.
1250 if ( cssPending
=== 0 ) {
1252 // This callback is exposed to addEmbeddedCSS, which is outside the execute()
1253 // function and is not concerned with state-machine integrity. In turn,
1254 // addEmbeddedCSS() actually exposes stuff further into the browser (rAF).
1255 // If increment and decrement callbacks happen in the wrong order, or start
1256 // again afterwards, then this branch could be reached multiple times.
1257 // To protect the integrity of the state-machine, prevent that from happening
1258 // by making runScript() cannot be called more than once. We store a private
1259 // reference when we first reach this branch, then deference the original, and
1260 // call our reference to it.
1261 runScriptCopy
= runScript
;
1262 runScript
= undefined;
1268 // Process styles (see also mw.loader.implement)
1269 // * back-compat: { <media>: css }
1270 // * back-compat: { <media>: [url, ..] }
1271 // * { "css": [css, ..] }
1272 // * { "url": { <media>: [url, ..] } }
1273 if ( registry
[ module
].style
) {
1274 for ( key
in registry
[ module
].style
) {
1275 value
= registry
[ module
].style
[ key
];
1278 if ( key
!== 'url' && key
!== 'css' ) {
1279 // Backwards compatibility, key is a media-type
1280 if ( typeof value
=== 'string' ) {
1281 // back-compat: { <media>: css }
1282 // Ignore 'media' because it isn't supported (nor was it used).
1283 // Strings are pre-wrapped in "@media". The media-type was just ""
1284 // (because it had to be set to something).
1285 // This is one of the reasons why this format is no longer used.
1286 addEmbeddedCSS( value
, cssHandle() );
1288 // back-compat: { <media>: [url, ..] }
1294 // Array of css strings in key 'css',
1295 // or back-compat array of urls from media-type
1296 if ( Array
.isArray( value
) ) {
1297 for ( i
= 0; i
< value
.length
; i
++ ) {
1298 if ( key
=== 'bc-url' ) {
1299 // back-compat: { <media>: [url, ..] }
1300 addLink( media
, value
[ i
] );
1301 } else if ( key
=== 'css' ) {
1302 // { "css": [css, ..] }
1303 addEmbeddedCSS( value
[ i
], cssHandle() );
1306 // Not an array, but a regular object
1307 // Array of urls inside media-type key
1308 } else if ( typeof value
=== 'object' ) {
1309 // { "url": { <media>: [url, ..] } }
1310 for ( media
in value
) {
1311 urls
= value
[ media
];
1312 for ( i
= 0; i
< urls
.length
; i
++ ) {
1313 addLink( media
, urls
[ i
] );
1320 // End profiling of execute()-self before we call runScript(),
1321 // which we want to measure separately without overlap.
1322 $CODE
.profileExecuteEnd();
1324 if ( module
=== 'user' ) {
1325 // Implicit dependency on the site module. Not a real dependency because it should
1326 // run after 'site' regardless of whether it succeeds or fails.
1327 // Note: This is a simplified version of mw.loader.using(), inlined here because
1328 // mw.loader.using() is part of mediawiki.base (depends on jQuery; T192623).
1330 siteDeps
= resolve( [ 'site' ] );
1335 if ( siteDepErr
=== undefined ) {
1336 enqueue( siteDeps
, runScript
, runScript
);
1338 } else if ( cssPending
=== 0 ) {
1339 // Regular module without styles
1342 // else: runScript will get called via cssHandle()
1345 function sortQuery( o
) {
1354 for ( key
= 0; key
< a
.length
; key
++ ) {
1355 sorted
[ a
[ key
] ] = o
[ a
[ key
] ];
1361 * Converts a module map of the form `{ foo: [ 'bar', 'baz' ], bar: [ 'baz, 'quux' ] }`
1362 * to a query string of the form `foo.bar,baz|bar.baz,quux`.
1364 * See `ResourceLoader::makePackedModulesString()` in PHP, of which this is a port.
1365 * On the server, unpacking is done by `ResourceLoaderContext::expandModuleNames()`.
1367 * Note: This is only half of the logic, the other half has to be in #batchRequest(),
1368 * because its implementation needs to keep track of potential string size in order
1369 * to decide when to split the requests due to url size.
1372 * @param {Object} moduleMap Module map
1374 * @return {string} return.str Module query string
1375 * @return {Array} return.list List of module names in matching order
1377 function buildModulesString( moduleMap
) {
1382 function restore( suffix
) {
1386 for ( prefix
in moduleMap
) {
1387 p
= prefix
=== '' ? '' : prefix
+ '.';
1388 str
.push( p
+ moduleMap
[ prefix
].join( ',' ) );
1389 list
.push
.apply( list
, moduleMap
[ prefix
].map( restore
) );
1392 str
: str
.join( '|' ),
1398 * Resolve indexed dependencies.
1400 * ResourceLoader uses an optimisation to save space which replaces module names in
1401 * dependency lists with the index of that module within the array of module
1402 * registration data if it exists. The benefit is a significant reduction in the data
1403 * size of the startup module. This function changes those dependency lists back to
1404 * arrays of strings.
1407 * @param {Array} modules Modules array
1409 function resolveIndexedDependencies( modules
) {
1411 function resolveIndex( dep
) {
1412 return typeof dep
=== 'number' ? modules
[ dep
][ 0 ] : dep
;
1414 for ( i
= 0; i
< modules
.length
; i
++ ) {
1415 deps
= modules
[ i
][ 2 ];
1417 for ( j
= 0; j
< deps
.length
; j
++ ) {
1418 deps
[ j
] = resolveIndex( deps
[ j
] );
1426 * @param {Object} params Map of parameter names to values
1429 function makeQueryString( params
) {
1430 return Object
.keys( params
).map( function ( key
) {
1431 return encodeURIComponent( key
) + '=' + encodeURIComponent( params
[ key
] );
1436 * Create network requests for a batch of modules.
1438 * This is an internal method for #work(). This must not be called directly
1439 * unless the modules are already registered, and no request is in progress,
1440 * and the module state has already been set to `loading`.
1443 * @param {string[]} batch
1445 function batchRequest( batch
) {
1446 var reqBase
, splits
, maxQueryLength
, b
, bSource
, bGroup
,
1447 source
, group
, i
, modules
, sourceLoadScript
,
1448 currReqBase
, currReqBaseLength
, moduleMap
, currReqModules
, l
,
1449 lastDotIndex
, prefix
, suffix
, bytesAdded
;
1452 * Start the currently drafted request to the server.
1456 function doRequest() {
1457 // Optimisation: Inherit (Object.create), not copy ($.extend)
1458 var query
= Object
.create( currReqBase
),
1459 packed
= buildModulesString( moduleMap
);
1460 query
.modules
= packed
.str
;
1461 // The packing logic can change the effective order, even if the input was
1462 // sorted. As such, the call to getCombinedVersion() must use this
1463 // effective order, instead of currReqModules, as otherwise the combined
1464 // version will not match the hash expected by the server based on
1465 // combining versions from the module query string in-order. (T188076)
1466 query
.version
= getCombinedVersion( packed
.list
);
1467 query
= sortQuery( query
);
1468 addScript( sourceLoadScript
+ '?' + makeQueryString( query
) );
1471 if ( !batch
.length
) {
1475 // Always order modules alphabetically to help reduce cache
1476 // misses for otherwise identical content.
1479 // Query parameters common to all requests
1481 skin
: mw
.config
.get( 'skin' ),
1482 lang
: mw
.config
.get( 'wgUserLanguage' ),
1483 debug
: mw
.config
.get( 'debug' )
1485 maxQueryLength
= mw
.config
.get( 'wgResourceLoaderMaxQueryLength', 2000 );
1487 // Split module list by source and by group.
1488 splits
= Object
.create( null );
1489 for ( b
= 0; b
< batch
.length
; b
++ ) {
1490 bSource
= registry
[ batch
[ b
] ].source
;
1491 bGroup
= registry
[ batch
[ b
] ].group
;
1492 if ( !splits
[ bSource
] ) {
1493 splits
[ bSource
] = Object
.create( null );
1495 if ( !splits
[ bSource
][ bGroup
] ) {
1496 splits
[ bSource
][ bGroup
] = [];
1498 splits
[ bSource
][ bGroup
].push( batch
[ b
] );
1501 for ( source
in splits
) {
1502 sourceLoadScript
= sources
[ source
];
1504 for ( group
in splits
[ source
] ) {
1506 // Cache access to currently selected list of
1507 // modules for this group from this source.
1508 modules
= splits
[ source
][ group
];
1510 // Query parameters common to requests for this module group
1511 // Optimisation: Inherit (Object.create), not copy ($.extend)
1512 currReqBase
= Object
.create( reqBase
);
1513 // User modules require a user name in the query string.
1514 if ( group
=== 'user' && mw
.config
.get( 'wgUserName' ) !== null ) {
1515 currReqBase
.user
= mw
.config
.get( 'wgUserName' );
1518 // In addition to currReqBase, doRequest() will also add 'modules' and 'version'.
1519 // > '&modules='.length === 9
1520 // > '&version=1234567'.length === 16
1522 currReqBaseLength
= makeQueryString( currReqBase
).length
+ 25;
1524 // We may need to split up the request to honor the query string length limit,
1525 // so build it piece by piece.
1526 l
= currReqBaseLength
;
1527 moduleMap
= Object
.create( null ); // { prefix: [ suffixes ] }
1528 currReqModules
= [];
1530 for ( i
= 0; i
< modules
.length
; i
++ ) {
1531 // Determine how many bytes this module would add to the query string
1532 lastDotIndex
= modules
[ i
].lastIndexOf( '.' );
1533 // If lastDotIndex is -1, substr() returns an empty string
1534 prefix
= modules
[ i
].substr( 0, lastDotIndex
);
1535 suffix
= modules
[ i
].slice( lastDotIndex
+ 1 );
1536 bytesAdded
= moduleMap
[ prefix
] ?
1537 suffix
.length
+ 3 : // '%2C'.length == 3
1538 modules
[ i
].length
+ 3; // '%7C'.length == 3
1540 // If the url would become too long, create a new one, but don't create empty requests
1541 if ( maxQueryLength
> 0 && currReqModules
.length
&& l
+ bytesAdded
> maxQueryLength
) {
1542 // Dispatch what we've got...
1544 // .. and start again.
1545 l
= currReqBaseLength
;
1546 moduleMap
= Object
.create( null );
1547 currReqModules
= [];
1549 mw
.track( 'resourceloader.splitRequest', { maxQueryLength
: maxQueryLength
} );
1551 if ( !moduleMap
[ prefix
] ) {
1552 moduleMap
[ prefix
] = [];
1555 moduleMap
[ prefix
].push( suffix
);
1556 currReqModules
.push( modules
[ i
] );
1558 // If there's anything left in moduleMap, request that too
1559 if ( currReqModules
.length
) {
1568 * @param {string[]} implementations Array containing pieces of JavaScript code in the
1569 * form of calls to mw.loader#implement().
1570 * @param {Function} cb Callback in case of failure
1571 * @param {Error} cb.err
1573 function asyncEval( implementations
, cb
) {
1574 if ( !implementations
.length
) {
1577 mw
.requestIdleCallback( function () {
1579 domEval( implementations
.join( ';' ) );
1587 * Make a versioned key for a specific module.
1590 * @param {string} module Module name
1591 * @return {string|null} Module key in format '`[name]@[version]`',
1592 * or null if the module does not exist
1594 function getModuleKey( module
) {
1595 return hasOwn
.call( registry
, module
) ?
1596 ( module
+ '@' + registry
[ module
].version
) : null;
1601 * @param {string} key Module name or '`[name]@[version]`'
1604 function splitModuleKey( key
) {
1605 var index
= key
.indexOf( '@' );
1606 if ( index
=== -1 ) {
1613 name
: key
.slice( 0, index
),
1614 version
: key
.slice( index
+ 1 )
1620 * @param {string} module
1621 * @param {string|number} [version]
1622 * @param {string[]} [dependencies]
1623 * @param {string} [group]
1624 * @param {string} [source]
1625 * @param {string} [skip]
1627 function registerOne( module
, version
, dependencies
, group
, source
, skip
) {
1628 if ( hasOwn
.call( registry
, module
) ) {
1629 throw new Error( 'module already registered: ' + module
);
1631 registry
[ module
] = {
1632 // Exposed to execute() for mw.loader.implement() closures.
1633 // Import happens via require().
1637 version
: String( version
|| '' ),
1638 dependencies
: dependencies
|| [],
1639 group
: typeof group
=== 'string' ? group
: null,
1640 source
: typeof source
=== 'string' ? source
: 'local',
1641 state
: 'registered',
1642 skip
: typeof skip
=== 'string' ? skip
: null
1646 /* Public Members */
1649 * The module registry is exposed as an aid for debugging and inspecting page
1650 * state; it is not a public interface for modifying the registry.
1656 moduleRegistry
: registry
,
1659 * @inheritdoc #newStyleTag
1662 addStyleTag
: newStyleTag
,
1669 * Start loading of all queued module dependencies.
1674 var q
, batch
, implementations
, sourceModules
;
1678 // Appends a list of modules from the queue to the batch
1679 for ( q
= 0; q
< queue
.length
; q
++ ) {
1680 // Only load modules which are registered
1681 if ( hasOwn
.call( registry
, queue
[ q
] ) && registry
[ queue
[ q
] ].state
=== 'registered' ) {
1682 // Prevent duplicate entries
1683 if ( batch
.indexOf( queue
[ q
] ) === -1 ) {
1684 batch
.push( queue
[ q
] );
1685 // Mark registered modules as loading
1686 registry
[ queue
[ q
] ].state
= 'loading';
1691 // Now that the queue has been processed into a batch, clear the queue.
1692 // This MUST happen before we initiate any eval or network request. Otherwise,
1693 // it is possible for a cached script to instantly trigger the same work queue
1694 // again; all before we've cleared it causing each request to include modules
1695 // which are already loaded.
1698 if ( !batch
.length
) {
1702 mw
.loader
.store
.init();
1703 if ( mw
.loader
.store
.enabled
) {
1704 implementations
= [];
1706 batch
= batch
.filter( function ( module
) {
1707 var implementation
= mw
.loader
.store
.get( module
);
1708 if ( implementation
) {
1709 implementations
.push( implementation
);
1710 sourceModules
.push( module
);
1715 asyncEval( implementations
, function ( err
) {
1717 // Not good, the cached mw.loader.implement calls failed! This should
1718 // never happen, barring ResourceLoader bugs, browser bugs and PEBKACs.
1719 // Depending on how corrupt the string is, it is likely that some
1720 // modules' implement() succeeded while the ones after the error will
1721 // never run and leave their modules in the 'loading' state forever.
1722 mw
.loader
.store
.stats
.failed
++;
1724 // Since this is an error not caused by an individual module but by
1725 // something that infected the implement call itself, don't take any
1726 // risks and clear everything in this cache.
1727 mw
.loader
.store
.clear();
1729 mw
.trackError( 'resourceloader.exception', {
1731 source
: 'store-eval'
1733 // Re-add the failed ones that are still pending back to the batch
1734 failed
= sourceModules
.filter( function ( module
) {
1735 return registry
[ module
].state
=== 'loading';
1737 batchRequest( failed
);
1741 batchRequest( batch
);
1745 * Register a source.
1747 * The #work() method will use this information to split up requests by source.
1749 * mw.loader.addSource( { mediawikiwiki: 'https://www.mediawiki.org/w/load.php' } );
1752 * @param {Object} ids An object mapping ids to load.php end point urls
1753 * @throws {Error} If source id is already registered
1755 addSource: function ( ids
) {
1758 if ( hasOwn
.call( sources
, id
) ) {
1759 throw new Error( 'source already registered: ' + id
);
1761 sources
[ id
] = ids
[ id
];
1766 * Register a module, letting the system know about it and its properties.
1768 * The startup module calls this method.
1770 * When using multiple module registration by passing an array, dependencies that
1771 * are specified as references to modules within the array will be resolved before
1772 * the modules are registered.
1774 * @param {string|Array} modules Module name or array of arrays, each containing
1775 * a list of arguments compatible with this method
1776 * @param {string|number} [version] Module version hash (falls backs to empty string)
1777 * Can also be a number (timestamp) for compatibility with MediaWiki 1.25 and earlier.
1778 * @param {string[]} [dependencies] Array of module names on which this module depends.
1779 * @param {string} [group=null] Group which the module is in
1780 * @param {string} [source='local'] Name of the source
1781 * @param {string} [skip=null] Script body of the skip function
1783 register: function ( modules
) {
1785 if ( typeof modules
=== 'object' ) {
1786 resolveIndexedDependencies( modules
);
1787 // Optimisation: Up to 55% faster.
1788 // Typically called only once, and with a batch.
1789 // See <https://gist.github.com/Krinkle/f06fdb3de62824c6c16f02a0e6ce0e66>
1790 // Benchmarks taught us that the code for adding an object to `registry`
1791 // should actually be inline, or in a simple function that does no
1792 // arguments manipulation, and isn't also the caller itself.
1793 // JS semantics make it hard to optimise recursion to a different
1794 // signature of itself.
1795 for ( i
= 0; i
< modules
.length
; i
++ ) {
1796 registerOne
.apply( null, modules
[ i
] );
1799 registerOne
.apply( null, arguments
);
1804 * Implement a module given the components that make up the module.
1806 * When #load() or #using() requests one or more modules, the server
1807 * response contain calls to this function.
1809 * @param {string} module Name of module and current module version. Formatted
1810 * as '`[name]@[version]`". This version should match the requested version
1811 * (from #batchRequest and #registry). This avoids race conditions (T117587).
1812 * For back-compat with MediaWiki 1.27 and earlier, the version may be omitted.
1813 * @param {Function|Array|string} [script] Function with module code, list of URLs
1814 * to load via `<script src>`, or string of module code for `$.globalEval()`.
1815 * @param {Object} [style] Should follow one of the following patterns:
1817 * { "css": [css, ..] }
1818 * { "url": { <media>: [url, ..] } }
1820 * And for backwards compatibility (needs to be supported forever due to caching):
1823 * { <media>: [url, ..] }
1825 * The reason css strings are not concatenated anymore is T33676. We now check
1826 * whether it's safe to extend the stylesheet.
1829 * @param {Object} [messages] List of key/value pairs to be added to mw#messages.
1830 * @param {Object} [templates] List of key/value pairs to be added to mw#templates.
1832 implement: function ( module
, script
, style
, messages
, templates
) {
1833 var split
= splitModuleKey( module
),
1835 version
= split
.version
;
1836 // Automatically register module
1837 if ( !hasOwn
.call( registry
, name
) ) {
1838 mw
.loader
.register( name
);
1840 // Check for duplicate implementation
1841 if ( registry
[ name
].script
!== undefined ) {
1842 throw new Error( 'module already implemented: ' + name
);
1845 // Without this reset, if there is a version mismatch between the
1846 // requested and received module version, then mw.loader.store would
1847 // cache the response under the requested key. Thus poisoning the cache
1848 // indefinitely with a stale value. (T117587)
1849 registry
[ name
].version
= version
;
1851 // Attach components
1852 registry
[ name
].script
= script
|| null;
1853 registry
[ name
].style
= style
|| null;
1854 registry
[ name
].messages
= messages
|| null;
1855 registry
[ name
].templates
= templates
|| null;
1856 // The module may already have been marked as erroneous
1857 if ( registry
[ name
].state
!== 'error' && registry
[ name
].state
!== 'missing' ) {
1858 registry
[ name
].state
= 'loaded';
1859 if ( allWithImplicitReady( name
) ) {
1866 * Load an external script or one or more modules.
1868 * This method takes a list of unrelated modules. Use cases:
1870 * - A web page will be composed of many different widgets. These widgets independently
1871 * queue their ResourceLoader modules (`OutputPage::addModules()`). If any of them
1872 * have problems, or are no longer known (e.g. cached HTML), the other modules
1873 * should still be loaded.
1874 * - This method is used for preloading, which must not throw. Later code that
1875 * calls #using() will handle the error.
1877 * @param {string|Array} modules Either the name of a module, array of modules,
1878 * or a URL of an external script or style
1879 * @param {string} [type='text/javascript'] MIME type to use if calling with a URL of an
1880 * external script or style; acceptable values are "text/css" and
1881 * "text/javascript"; if no type is provided, text/javascript is assumed.
1883 load: function ( modules
, type
) {
1886 // Allow calling with a url or single dependency as a string
1887 if ( typeof modules
=== 'string' ) {
1888 // "https://example.org/x.js", "http://example.org/x.js", "//example.org/x.js", "/x.js"
1889 if ( /^(https?:)?\/?\//.test( modules
) ) {
1890 if ( type
=== 'text/css' ) {
1891 l
= document
.createElement( 'link' );
1892 l
.rel
= 'stylesheet';
1894 document
.head
.appendChild( l
);
1897 if ( type
=== 'text/javascript' || type
=== undefined ) {
1898 addScript( modules
);
1902 throw new Error( 'invalid type for external url, must be text/css or text/javascript. not ' + type
);
1904 // Called with single module
1905 modules
= [ modules
];
1908 // Filter out top-level modules that are unknown or failed to load before.
1909 filtered
= modules
.filter( function ( module
) {
1910 var state
= mw
.loader
.getState( module
);
1911 return state
!== 'error' && state
!== 'missing';
1913 // Resolve remaining list using the known dependency tree.
1914 // This also filters out modules with unknown dependencies. (T36853)
1915 filtered
= resolveStubbornly( filtered
);
1916 // Some modules are not yet ready, add to module load queue.
1917 enqueue( filtered
, undefined, undefined );
1921 * Change the state of one or more modules.
1923 * @param {Object} modules Object of module name/state pairs
1925 state: function ( modules
) {
1927 for ( module
in modules
) {
1928 state
= modules
[ module
];
1929 if ( !hasOwn
.call( registry
, module
) ) {
1930 mw
.loader
.register( module
);
1932 registry
[ module
].state
= state
;
1933 if ( state
=== 'ready' || state
=== 'error' || state
=== 'missing' ) {
1934 // Make sure pending modules depending on this one get executed if their
1935 // dependencies are now fulfilled!
1936 handlePending( module
);
1942 * Get the version of a module.
1944 * @param {string} module Name of module
1945 * @return {string|null} The version, or null if the module (or its version) is not
1948 getVersion: function ( module
) {
1949 return hasOwn
.call( registry
, module
) ? registry
[ module
].version
: null;
1953 * Get the state of a module.
1955 * @param {string} module Name of module
1956 * @return {string|null} The state, or null if the module (or its state) is not
1959 getState: function ( module
) {
1960 return hasOwn
.call( registry
, module
) ? registry
[ module
].state
: null;
1964 * Get the names of all registered modules.
1968 getModuleNames: function () {
1969 return Object
.keys( registry
);
1973 * Get the exported value of a module.
1975 * This static method is publicly exposed for debugging purposes
1976 * only and must not be used in production code. In production code,
1977 * please use the dynamically provided `require()` function instead.
1979 * In case of lazy-loaded modules via mw.loader#using(), the returned
1980 * Promise provides the function, see #using() for examples.
1984 * @param {string} moduleName Module name
1985 * @return {Mixed} Exported value
1987 require: function ( moduleName
) {
1988 var state
= mw
.loader
.getState( moduleName
);
1990 // Only ready modules can be required
1991 if ( state
!== 'ready' ) {
1992 // Module may've forgotten to declare a dependency
1993 throw new Error( 'Module "' + moduleName
+ '" is not loaded.' );
1996 return registry
[ moduleName
].module
.exports
;
2000 * On browsers that implement the localStorage API, the module store serves as a
2001 * smart complement to the browser cache. Unlike the browser cache, the module store
2002 * can slice a concatenated response from ResourceLoader into its constituent
2003 * modules and cache each of them separately, using each module's versioning scheme
2004 * to determine when the cache should be invalidated.
2008 * @class mw.loader.store
2011 // Whether the store is in use on this page.
2014 // Modules whose string representation exceeds 100 kB are
2015 // ineligible for storage. See bug T66721.
2016 MODULE_SIZE_MAX
: 100 * 1000,
2018 // The contents of the store, mapping '[name]@[version]' keys
2019 // to module implementations.
2022 // Names of modules to be stored during the next update.
2023 // See add() and update().
2027 stats
: { hits
: 0, misses
: 0, expired
: 0, failed
: 0 },
2030 * Construct a JSON-serializable object representing the content of the store.
2032 * @return {Object} Module store contents.
2034 toJSON: function () {
2035 return { items
: mw
.loader
.store
.items
, vary
: mw
.loader
.store
.getVary() };
2039 * Get the localStorage key for the entire module store. The key references
2040 * $wgDBname to prevent clashes between wikis which share a common host.
2042 * @return {string} localStorage item key
2044 getStoreKey: function () {
2045 return 'MediaWikiModuleStore:' + mw
.config
.get( 'wgDBname' );
2049 * Get a key on which to vary the module cache.
2051 * @return {string} String of concatenated vary conditions.
2053 getVary: function () {
2054 return mw
.config
.get( 'skin' ) + ':' +
2055 mw
.config
.get( 'wgResourceLoaderStorageVersion' ) + ':' +
2056 mw
.config
.get( 'wgUserLanguage' );
2060 * Initialize the store.
2062 * Retrieves store from localStorage and (if successfully retrieved) decoding
2063 * the stored JSON value to a plain object.
2065 * The try / catch block is used for JSON & localStorage feature detection.
2066 * See the in-line documentation for Modernizr's localStorage feature detection
2067 * code for a full account of why we need a try / catch:
2068 * <https://github.com/Modernizr/Modernizr/blob/v2.7.1/modernizr.js#L771-L796>.
2073 if ( this.enabled
!== null ) {
2079 // Disabled because localStorage quotas are tight and (in Firefox's case)
2080 // shared by multiple origins.
2081 // See T66721, and <https://bugzilla.mozilla.org/show_bug.cgi?id=1064466>.
2082 /Firefox/.test( navigator
.userAgent
) ||
2084 // Disabled by configuration.
2085 !mw
.config
.get( 'wgResourceLoaderStorageEnabled' )
2087 // Clear any previous store to free up space. (T66721)
2089 this.enabled
= false;
2092 if ( mw
.config
.get( 'debug' ) ) {
2093 // Disable module store in debug mode
2094 this.enabled
= false;
2099 // This a string we stored, or `null` if the key does not (yet) exist.
2100 raw
= localStorage
.getItem( this.getStoreKey() );
2101 // If we get here, localStorage is available; mark enabled
2102 this.enabled
= true;
2103 // If null, JSON.parse() will cast to string and re-parse, still null.
2104 data
= JSON
.parse( raw
);
2105 if ( data
&& typeof data
.items
=== 'object' && data
.vary
=== this.getVary() ) {
2106 this.items
= data
.items
;
2110 mw
.trackError( 'resourceloader.exception', {
2112 source
: 'store-localstorage-init'
2116 // If we get here, one of four things happened:
2118 // 1. localStorage did not contain our store key.
2119 // This means `raw` is `null`, and we're on a fresh page view (cold cache).
2120 // The store was enabled, and `items` starts fresh.
2122 // 2. localStorage contained parseable data under our store key,
2123 // but it's not applicable to our current context (see getVary).
2124 // The store was enabled, and `items` starts fresh.
2126 // 3. JSON.parse threw (localStorage contained corrupt data).
2127 // This means `raw` contains a string.
2128 // The store was enabled, and `items` starts fresh.
2130 // 4. localStorage threw (disabled or otherwise unavailable).
2131 // This means `raw` was never assigned.
2132 // We will disable the store below.
2133 if ( raw
=== undefined ) {
2134 // localStorage failed; disable store
2135 this.enabled
= false;
2140 * Retrieve a module from the store and update cache hit stats.
2142 * @param {string} module Module name
2143 * @return {string|boolean} Module implementation or false if unavailable
2145 get: function ( module
) {
2148 if ( !this.enabled
) {
2152 key
= getModuleKey( module
);
2153 if ( key
in this.items
) {
2155 return this.items
[ key
];
2157 this.stats
.misses
++;
2162 * Queue the name of a module that the next update should consider storing.
2165 * @param {string} module Module name
2167 add: function ( module
) {
2168 if ( !this.enabled
) {
2171 this.queue
.push( module
);
2172 this.requestUpdate();
2176 * Add the contents of the named module to the in-memory store.
2178 * This method does not guarantee that the module will be stored.
2179 * Inspection of the module's meta data and size will ultimately decide that.
2181 * This method is considered internal to mw.loader.store and must only
2182 * be called if the store is enabled.
2185 * @param {string} module Module name
2187 set: function ( module
) {
2189 descriptor
= mw
.loader
.moduleRegistry
[ module
];
2191 key
= getModuleKey( module
);
2194 // Already stored a copy of this exact version
2195 key
in this.items
||
2196 // Module failed to load
2198 descriptor
.state
!== 'ready' ||
2199 // Unversioned, private, or site-/user-specific
2200 !descriptor
.version
||
2201 descriptor
.group
=== 'private' ||
2202 descriptor
.group
=== 'user' ||
2203 // Partial descriptor
2204 // (e.g. skipped module, or style module with state=ready)
2205 [ descriptor
.script
, descriptor
.style
, descriptor
.messages
,
2206 descriptor
.templates
].indexOf( undefined ) !== -1
2214 JSON
.stringify( key
),
2215 typeof descriptor
.script
=== 'function' ?
2216 String( descriptor
.script
) :
2217 JSON
.stringify( descriptor
.script
),
2218 JSON
.stringify( descriptor
.style
),
2219 JSON
.stringify( descriptor
.messages
),
2220 JSON
.stringify( descriptor
.templates
)
2223 mw
.trackError( 'resourceloader.exception', {
2225 source
: 'store-localstorage-json'
2230 src
= 'mw.loader.implement(' + args
.join( ',' ) + ');';
2231 if ( src
.length
> this.MODULE_SIZE_MAX
) {
2234 this.items
[ key
] = src
;
2238 * Iterate through the module store, removing any item that does not correspond
2239 * (in name and version) to an item in the module registry.
2241 prune: function () {
2244 for ( key
in this.items
) {
2245 module
= key
.slice( 0, key
.indexOf( '@' ) );
2246 if ( getModuleKey( module
) !== key
) {
2247 this.stats
.expired
++;
2248 delete this.items
[ key
];
2249 } else if ( this.items
[ key
].length
> this.MODULE_SIZE_MAX
) {
2250 // This value predates the enforcement of a size limit on cached modules.
2251 delete this.items
[ key
];
2257 * Clear the entire module store right now.
2259 clear: function () {
2262 localStorage
.removeItem( this.getStoreKey() );
2267 * Request a sync of the in-memory store back to persisted localStorage.
2269 * This function debounces updates. The debouncing logic should account
2270 * for the following factors:
2272 * - Writing to localStorage is an expensive operation that must not happen
2273 * during the critical path of initialising and executing module code.
2274 * Instead, it should happen at a later time after modules have been given
2275 * time and priority to do their thing first.
2277 * - This method is called from mw.loader.store.add(), which will be called
2278 * hundreds of times on a typical page, including within the same call-stack
2279 * and eventloop-tick. This is because responses from load.php happen in
2280 * batches. As such, we want to allow all modules from the same load.php
2281 * response to be written to disk with a single flush, not many.
2283 * - Repeatedly deleting and creating timers is non-trivial.
2285 * - localStorage is shared by all pages from the same origin, if multiple
2286 * pages are loaded with different module sets, the possibility exists that
2287 * modules saved by one page will be clobbered by another. The impact of
2288 * this is minor, it merely causes a less efficient cache use, and the
2289 * problem would be corrected by subsequent page views.
2291 * This method is considered internal to mw.loader.store and must only
2292 * be called if the store is enabled.
2297 requestUpdate
: ( function () {
2298 var hasPendingWrites
= false;
2300 function flushWrites() {
2303 // Remove anything from the in-memory store that came from previous page
2304 // loads that no longer corresponds with current module names and versions.
2305 mw
.loader
.store
.prune();
2306 // Process queued module names, serialise their contents to the in-memory store.
2307 while ( mw
.loader
.store
.queue
.length
) {
2308 mw
.loader
.store
.set( mw
.loader
.store
.queue
.shift() );
2311 key
= mw
.loader
.store
.getStoreKey();
2313 // Replacing the content of the module store might fail if the new
2314 // contents would exceed the browser's localStorage size limit. To
2315 // avoid clogging the browser with stale data, always remove the old
2316 // value before attempting to set the new one.
2317 localStorage
.removeItem( key
);
2318 data
= JSON
.stringify( mw
.loader
.store
);
2319 localStorage
.setItem( key
, data
);
2321 mw
.trackError( 'resourceloader.exception', {
2323 source
: 'store-localstorage-update'
2327 // Let the next call to requestUpdate() create a new timer.
2328 hasPendingWrites
= false;
2331 function onTimeout() {
2332 // Defer the actual write via requestIdleCallback
2333 mw
.requestIdleCallback( flushWrites
);
2336 return function () {
2337 // On the first call to requestUpdate(), create a timer that
2338 // waits at least two seconds, then calls onTimeout.
2339 // The main purpose is to allow the current batch of load.php
2340 // responses to complete before we do anything. This batch can
2341 // trigger many hundreds of calls to requestUpdate().
2342 if ( !hasPendingWrites
) {
2343 hasPendingWrites
= true;
2344 setTimeout( onTimeout
, 2000 );
2352 // Skeleton user object, extended by the 'mediawiki.user' module.
2359 * @property {mw.Map}
2363 * @property {mw.Map}
2368 // OOUI widgets specific to MediaWiki
2373 // Attach to window and globally alias
2374 window
.mw
= window
.mediaWiki
= mw
;