User:PerfektesChaos/js/preferencesGadgetOptions

Library with JavaScript functions to support configurable gadgets.

Core issue is an interactive dialog form easy to create on Special:Blankpage. Utilities are also manipulating the MediaWiki user preferences. Gadget options are available for anonymous users, too.

Features

Storing of information is done via API on MediaWiki server.

For retrieving the options set of the current page is evaluated, which has been transferred recently. However, an option might have been changed on a different page in another browser window.

Gadget configuration by GUI

From the form information a GUI is built on Special:Blankpage on the fly. If confirmed by + the last desires of the user will be stored as preferences and may be retrieved on any other page.

Project wide defined tools listed on MediaWiki:Gadgets-definition appear on Special:Blankpage anyway. If a configuration dialog has been defined and the user selected this particular tool, a button is added to the existing entry.

User scripts which are not registered as project gadgets get their own section on top of the special page.

Even if no configuration is supported, a link to documentation page may be displayed, and correct installation and presence is confirmd by visible entry.

Type safe user JS

The MediaWiki supports only string values. Since "false" shows very different behaviour on control structures than false (and "null" is not null nor is "5"+7 the same as 5+7) single values are returned as stored.

Entire option sets of a gadget are stored by JSON which keeps type.

Preferences

Some utility functions support common MediaWiki user preferences:

String setting
Updating

Only strings may be assigned as MediaWiki standard preferences, and the value has to be valid as if entered on Special:Preferences.

Updating

It is possible to update a particular option within the current page. The page might have been delivered some time ago, while the value has been changed within another browser window.

Callback

If wiki server needs to be contacted, the return values of functions are not the ultimate responses. If an updated value is to be retrieved from server, it will arrive with some delay on a callback function. Notification about successful storage may be requested as well as alerting on exchange errors.

User defined preferences storing

Currently the following component range is used for storing of preferences other than from MediaWiki extensions:

mw.user.options.values.userjs-gadgetID

This might change one day, perhaps

mw.user.config.values.gadgetID

The script maintains independent access to this storage, even automatic migration.

Data consumption

Every time a user is requesting a page (after login), the entire set of options is transferred from server. No caching on local browser storage is done.
For better management and faster network communication there is only one object with the entire option set for each gadget.
- This is much more efficient than a gadget identifier combine with a single option name for each value.
- It also enables easy combination with an entire set of default values modified by user preferences.
The amount of data which needs to be transferred every time should be kept small. Persistent configuration information should be put into specific configuration script pages hold by browser cache, or put into localStorage/sessionStorage (Web Storage) after first access.

Anonymous users

While preferences and gadget options are stored on a wiki server if login performed, anonymous users may recall gadget options at least within the same browser profile.

The web storage feature, which is available on all recent major browsers will save information between pages and sessions.

Anonymous users may use greasemonkey to trigger any script.

Gadget maintainers need not to know whether options have been saved on server or locally.

Installation

Gadget programmers need to wait for correct installation of this script before any function can be used.

If the gadget decided that the library is needed, the following code will load the source if not yet present.

if ( ! mw.loader.getState( "ext.gadget.preferencesGadgetOptions" ) ) {
   mw.loader.state( { "ext.gadget.preferencesGadgetOptions": "loading" } );
   mw.loader.load( "http://en.wiki.x.io/w/index.php?title="
                   + "User:PerfektesChaos/js/"
                   + "preferencesGadgetOptions/r.js"
                   + "&action=raw&bcache=1&maxage=604800"
                   + "&ctype=text/javascript" );
}
mw.hook( "preferencesGadgetOptions.ready" ).add( callback );

The state of this script is checked first to avoid repeated loading. Another gadget which also uses this script library might be loading already. Therefore the state is set to "loading" immediately.

A callback function will be executed as soon as loading has been completed, or right now, if already available. All functionality relying on the library is to be accessed within the callback function. The callback function will receive the library object as first parameter.

API

After the mw.hook preferencesGadgetOptions.ready has been triggered functions may be called. The application object is the parameter of the mw.hook callback function and should be identical with mw.libs.preferencesGadgetOptions.

All functions are components of the application object.

Survey
function	scope			purpose
function	Gadgets	UserJS	MediaWiki	purpose
`.fetch()`	×	–	–	Retrieve option set
`.form()`				Dialog form on Special:Blankpage
`.forward()`				Store option set
`.$button()`				Retrieve jQuery button opening special page
`.get()`	–	×	–	Retrieve typesafe single userjs option
`.put()`	–	×	–	Store typesafe single userjs option
`.remove()`	×	×	×	Remove user option from preferences
`.string()`	–	–	×	Store MediaWiki preference string
`.update()`	–	–	×	Update the value of a MediaWiki preference

.fetch()

Retrieve a “Gadgets” option set stored by .form() or .forward().

Parameter	Type	Meaning
Call	`.fetch(assign, assume, again, aborted)`
`assign`	`string`	gadget identification
`assume`	`object`	`object` – fallback components if no option set retrieved or some components missing; kept unchanged `undefined`, `null`, `false` – no defaults
`again`	`function` `boolean`	update value from server function – callback function, when updated `true` – just do it `undefined`, `false` – do not contact server
`aborted`	`function`	attempt to update `again` failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		`object` as of current page state and `assume`; could be `null`

This functionality is also available as hook.

.form()

Show gadget (entry, and dialog) on Special:Blankpage. If already registered by project, only append button to open form, if any.

Parameter	Type	Meaning
Call	`.form(about)`
`about`	`object`	gadget description, see below

This functionality is also available as hook.

.forward()

Store a "Gadgets" options object.

Parameter	Type	Meaning
Call	`.forward(assign, apply, after, aborted)`
`assign`	`string`	gadget identification
`apply`	`object`	key:value assignments as needed
`after`	`function` `boolean`	storing succeeded function – callback function, when updated `undefined`, `false` – no feedback
`aborted`	`function`	storing failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		`false` if valid, else error message on parameter fault

This functionality is also available as hook.

.$button()

Retrieve a jQuery button in current design, opening the Special:Blankpage.

Parameter	Type	Meaning
Call	`.button(assign)`
`assign`	`string` optional	gadget identification; opens specified options form on Special:Blankpage.
Return value		jQuery button

This functionality is also available as hook.

.get()

Retrieve a typesafe USERJS option value stored by .put().

Parameter	Type	Meaning
Call	`.get(assign, assume, again, abort)`
`assign`	`string`	gadget identification
`assume`	any optional	fallback value if not retrieved or missing
`again`	`function` `boolean`	update value from server function – callback function, when updated `true` – just do it `undefined`, `false` – do not contact server
`aborted`	`function`	attempt to update `again` failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		value, of any type; at least `assume`

.put()

Store a typesafe USERJS option value. Supposed to be retrieved by .get().

Parameter	Type	Meaning
Call	`.put(assign, apply, after, aborted)`
`assign`	`string`	gadget identification
`apply`	any	value to be stored.
`after`	`function`	storing succeeded function – callback function, when updated `undefined`, `false` – no feedback
`aborted`	`function`	storing failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		`false` if valid, else error message on parameter fault

.remove()

Remove a user option entry from preferences.

Parameter	Type	Meaning
Call	`.remove(assign, after, aborted)`
`assign`	`string`	option identification
`after`	`function`	deletion performed function – callback function, when updated `undefined`, `false` – no feedback
`aborted`	`function`	deletion failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		`false` if valid, else error message on parameter fault

.string()

Store a string value of a MEDIAWIKI option.

Parameter	Type	Meaning
Call	`.string(assign, apply, after, aborted)`
`assign`	`string`	MediaWiki option name
`apply`	`string`	value
`after`	`function`	storing succeeded function – callback function, when updated `undefined`, `false` – no feedback
`aborted`	`function`	storing failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		`false` if valid, else error message on parameter fault

.update()

Update the value of a MEDIAWIKI option.

Parameter	Type	Meaning
Call	`.update(assign, after, aborted)`
`assign`	`string`	MediaWiki option name
`after`	`function`	updating successfully finished function – callback function, when updated `undefined`, `false` – no feedback
`aborted`	`function`	updating failed function – callback function, if server denied `undefined`, `false` – no further notification
Return value		`false` if valid, else error message on parameter fault

GUI for Special:Blankpage

User and project defined gadgets may be advertised and configured on Special:Blankpage page.

If already defined by MediaWiki:Gadgets-definition and chosen by user, only append button to open form, if any.
If user script has not been registered as project gadget a particular section will be inserted on top of the special page. Every unregistered user script gets an entry and may link to its documentation page.

If the about.opts is specified a button is appended to open a dialog form, which may be closed again later.

The form provides a submit button + that launches a page and server update if clicked.

From the following components all but .script are optional; but some more than the gadget ID only make look the GUI pretty and functional.

`about` object in `.form()`
Component	Type	Meaning
`.script`	`string`	mandatory gadget ID
`.suite`	`string`	ID in MediaWiki:Gadgets-definition `.script` if not defined
`.show`	`string`	displayed name of gadget `.script` if not defined
`.support`	`string`	URL of gadget documentation page "/wiki/User:PerfektesChaos/js/preferencesGadgetOptions"
`.suffix`	`string`	further explanation of the gadget (an opt-in user should already know) Is appended to the name `.show` of the gadget.
`.fiat`	`function`	function called after `.opts` equipped the form. In `.opts` all jQuery objects of controls `.$checkbox .$item .$text` are contained now and may be used for definition of complex multilateral relations by on-functions. The function receives as first parameter the object `about` and as second parameter the jQuery object of the submit button +. `this` is the `about` object.
`.filled`	`function`	function called after submit button + has been pressed. The function receives as first parameter the object `about` and as second parameter the object with all current values. `this` is the `about` object.
`.fed`	`function`	callback function executed after successful storing on server
`.failure`	`function`	callback function executed if storing on server failed
`.opts`	`Array`	configurable options Every element is an `object` and describes one option. Every element has two mandatory components: `.signature` and `.type` – should be accompanied by meaningful decorated content. Format of all elements described in next table.

Array `about.opts` element
Component	Type	Meaning
`.signature`	`string`	mandatory option ID
`.type`	`string`	mandatory option type; one of `checkbox` – single checkbox `radio` – radio button sequence; Array `.poly` required `multi` – checkbox sequence, multiple choice; Array `.poly` required `text` – single line of text
`.show`	`string`	option description
`.val`	any	default setting, and current choice
`.poly`	`Array`	multiple control definition (`.type=radio\|multi` only). Every Array element is an `object` with two components: `.val` – any type; will be assigned if chosen `.show` – `string` with description For `.type=multi` the resulting option value `.val` is an Array of the single `.poly[.val,.val]` elements and the checked `.type=radio` button value otherwise.
`.suffix`	`string`	`.type=text` only (optional) description appended to text input field may be wrapped as HTML element.
`.minimum`	`string`	`.type=text` only (optional) displayed length (guessed) of input field in characters
`.maxlength`	`number`	`.type=text` only (optional) maximum permitted length of input string in characters
`.ime`	`boolean`	`.type=text` only (optional) `true` – permit IME
`.field`	`function`	`.type=text` only (optional) Function receiving the jQuery object of input field as parameter. That might be equipped with on-functions and may set dependant background colours. `this` is this entire text option.
`.$checkbox` `.$item` `.$text`	`object`	jQuery object generated by the script after first opening of the form

Callback function

If desired a user defined function is called as soon as an action on Wiki server has been completed. These functions share the following specification:

Called with one parameter:
- For a function of successful execution this is the current option value.
- For a function in case of failure it is a string with best error description available.
this is the application object mw.libs.preferencesGadgetOptions.

Synchronisation

For vulnerable operations it might be crucial that configuration has not been changed within another window since the page has been displayed. By the updating function and callback functions it can be ensured that operations are not executed before the most recent state was taken into account.

Waiting for availability

It might happen that this library is unavailable or could crash due to syntax error or other situation.

The success function of .using() should check first availability of the object component mw.libs.preferencesGadgetOptions and the desired function components. If those are missing it needs to be continued with standard values without supporting specific user options.
This might be logged on console to help quick remediation.

Configuration of special page

For the entire project the default rearrangement of Special:Blankpage might be influenced by project administration, in particular by MediaWiki:Common.js which is executed in advance.

Change of project configuration by gadgets is not desired and might be treated by sysops as misuse.

Instead of default styles jQuery objects will be used if present. The following code could be completed to provide project specific design:

if ( mw.config.get( "wgCanonicalSpecialPageName" )  ===  "Blankpage" ) {
   mw.libs.preferencesGadgetOptions.config = {
      $btnOpts:     $( ... ),
      $sectionUser: $( ... ),
      ...
                                             };
}

Optional components in `.config`
jQuery objects
`.$sectionUser`	Wrapper object for the section on user defined scripts. `<div id="preferencesGadgetOptions-user">` Includes: Headline (H2) Border, colours etc. to distinguish from MediaWiki sections Some preliminary remarks on this section, if desired. One `<ul>` with the list of user defined scripts will be appended to this wrapper only.
`.$optsForm`	`<div class="preferencesGadgetOptions-optsForm">` for any single option form.
`.$btnOpts`	`<button>` control for opening an option form.
`.$btnSubmit`	`<button>` control for transmission of the options set.
`.$btnClose`	`<button>` control for closing an option form.
`.$throbber`	`<img>` for API in progress.
`.$stored`	`<img>` for successful storing on server.
`.$denied`	`<img>` for API failure.

The default design may be taken from the following CSS:

div.preferencesGadgetOptions-optsForm {
   border:  solid 1px #80FFFF;
   margin:  .5em;
   padding: .5em;
}
div#preferencesGadgetOptions-user {
   border:  solid 2px #80FFFF;
   margin:  1em;
   padding: 1em;
}

Hooks

The following identifiers are registered utilizing mw.hook() system:

Fired:
- preferencesGadgetOptions.ready
  when library has been provided and initialized, and user options are available. The parameter is the application library.
Listening:
- preferencesGadgetOptions.fetch
  Request for a Gadgets object stored by .form() or .forward(); parameters:
  - assigned – string with gadget identification
  - action – callback function, retrieves .fetch() result when available
  - assume – optional fallback value object, if undefined or failure
- preferencesGadgetOptions.form
  Like .form(); parameters:
  - about – object with gadget description
- preferencesGadgetOptions.forward
  Like .forward(); parameters:
  - assign – string with gadget identification
  - apply – options object (not null)
  - after – optional callback function, or false
  - aborted – optional callback function, or false
- preferencesGadgetOptions.$button
  Request for a [options button] design; parameters:
  - action – callback function, retrieves jQuery button when available
  - assign – optional string with gadget name

Hook listeners give the opportunity to fire and forget requests, with no need to wait until library has loaded.

Codes

Source code	Java Script – for load() human readable version
ResourceLoader	`ext.gadget.preferencesGadgetOptions` Dependencies: `user.options`
Namespaces	`-1` (`Gadgets`) Any page interesting for the application.
Cookies	Anonymous users only: `preferencesGadgetOptions` (localStorage)
`mw.libs`	`preferencesGadgetOptions`
`mw.hook`	`preferencesGadgetOptions.ready` Fired when library has been provided and initialized, and user options are available. More hooks listening; see above.
MediaWiki	1.26 (mw.storage) for anonymous users 1.23 for registered users

Known applications

Other languages

This gadget would be prepared for multilingual support but does not need any.

All language dependent strings are provided by the application if correctly used.
RTL of entire page is automatically taken into account for element arrangement.
If the application is not configured well red error messages in English might appear. These should be fixed by the programmer first.

Translations of this documentation are welcome.

German version