Manual:Tag extensions/es

A menudo, será útil para un proyecto dado extender el marcado wiki predefinido con funcionalidades adicionales, sea un simple procesamiento de cadenas de texto o la recuperación de información. Las extensiones de etiquetas permiten crear etiquetas personalizadas precisamente para hacer eso. Por ejemplo, se podría usar una extensión de etiqueta para introducir una simple etiqueta, que inyecta un formulario de donación en la página. Extensions, along with Parser Functions and Hooks are the most effective way to change or enhance the functionality of MediaWiki. You should always check the matrix before you start work on an extension to make sure someone else hasn't done exactly what you are trying to do.

A simple tag extension consists of a callback function, which is hooked to the parser so that, when the parser runs, it will find and replace all instances of a specific tag, calling the corresponding callback function to render the actual HTML.

Ejemplo
This example registers a callback function for the  tag. When a user adds this tag to a page like this:, the parser will call the   function, passing in four arguments:


 * $input : Input between the  and   tags, or null if the tag is "closed", i.e.
 * $args : Tag arguments, which are entered like HTML tag attributes; this is an associative array indexed by attribute name.
 * $parser : The parent parser (a Parser object); more advanced extensions use this to obtain the contextual Title, parse wiki text, expand braces, register link relationships and dependencies, etc.
 * $frame : The parent frame (a PPFrame object). This is used together with $parser to provide the parser with more complete information on the context in which the extension was called.

For a more elaborate example, see Tag extension example

Atributos
Veamos otro ejemplo:

Este ejemplo vuelca los atributos que se han pasado a la etiqueta, junto con sus valores. Es bastante evidente que esto permite especificar de forma flexible nuevas etiquetas personalizadas. Por ejemplo, puedes definir una extensión de etiqueta que permite que un usuario inyecte un formulario de contacto en su página de usuario mediante un código similar a.

Hay una verdadera plétora de extensiones de etiquetas disponibles para MediaWiki, algunas de las cuales se muestran en este sitio; otras se pueden encontrar mediante una búsqueda rápida en Internet. Aunque varias de estas extensiones están bastante especializadas para su caso de uso, también hay otras muy queridas y utilizadas que proporcionan varios grados de funcionalidad.

Convenciones
Véase para más información sobre el diseño general y la instalación de una extensión.

Publica tus propias extensiones

 * 1) Crea una nueva página en este wiki llamada Extension: con información sobre tu extensión, cómo instalarla y capturas de pantallas de la extensión en uso. Disponemos de una plantilla útil para almacenar este tipo de información llamada . Para más información, véase la página de la plantilla. Asimismo, deberías añadir toda la información que sea posible al cuerpo de la página. Es conveniente volver a consultar la página de forma regular para responder a las preguntas que tengan otros usuarios en la página de discusión asociada. Además, asegúrate de que la página pertenezca a.
 * 2) Extensions that create new hooks within the extension code should register them on extension hook registry.
 * 3) Notify the mediawiki-l mailing list.

See also publishing your extension.

Cuestiones de seguridad
Podrás ver que los datos introducidos en los ejemplos mostrados arriba están escapados mediante  antes de ser devueltos. Es crucial que se trate cualquier entrada de datos de esta manera antes de devolverla a los clientes, con el fin de evitar introducir vectores de inyección HTML, que puede dar lugar a vulnerabilidades de tipo cross-site scripting.

Carga de módulos
La forma correcta de añadir módulos a tu extensión es conactarlos a ParserOutput en vez de a $wgOut. La lista de módulos se sacará automáticamente del objeto ParserOutput y se adjuntará a $wgOut incluso cuando la carga de la página está preguardada en caché. Si añades directamente los módulos a $wgOut, puede que no se guarden en caché en la salida del analizador sintáctico.

Sincronización y extensiones
If you change the code for an extension, all pages that use the extension will, theoretically, immediately reflect the results of new code. Technically speaking, this means your code is executed each and every time a page containing the extension is rendered.

In practice, this is often not the case, due to page caching - either by the MediaWiki software, the browser or by an intermediary proxy or firewall.

To bypass MediaWiki's parser cache and ensure a new version of the page is generated, click on edit, replace "action=edit" in the URL shown in the address bar of your browser by "action=purge" and submit the new URL. The page and all templates it references will be regenerated, ignoring all cached data. The purge action is needed if the main page itself is not modified, but the way it must be rendered has changed (the extension was modified, or only a referenced template was modified).

Si esto no basta para obtener una copia nueva de la página, normalmente puedes saltar cualquier caché intermedia añadiendo '&rand=algúntextoaleatorio' al final de la URL. Asegúrate de que 'algúntextoaleatorio' sea distinto cada vez.

How do I disable caching for pages using my extension?
Since MediaWiki 1.5, the parser is passed as the third parameter to an extension. This parser can be used to invalidate the cache like this:

Regenerating the page when another page is edited
Maybe you don't want to disable caching entirely, you just want the page to be regenerated whenever another page is edited, similar to the way that template transclusions are handled. This can be done using the parser object that is passed to your hook function. The following method was lifted from CoreParserFunctions.php and appears to work for this purpose.

Fine grained adjustment of caching behavior
You can use fine grained caching for your extension by using cache keys to differentiate between different versions of your extension output. While rendering you can add cache keys for every feature by adding an addExtraKey method to your hook function, e.g.:

However, modifying $parser->getOptions during parse means that the extra option keys aren't included when trying to get a cached page, only when rendering a page to go into cache, so you can use the PageRenderingHash hook to set extra options. PageRenderingHash is run both when putting a page into cache, and getting it out, so its important to only add new keys to the hash if they're not already there. e.g:

Some important notes on this:


 * Using "!setting1=$value" instead of just "!$value" in the confstr ensures that the parser cache does not become messed up if different extensions are installed or their load order changes. ! is used a separator for different rendering options
 * Some people use  instead of  . Be warned that addExtraKey does not tell the parser cache that the extra key is in use, and thus can easily result in breaking the cache if you are not careful.

A partir de la versión 1.16
Parser hook functions are passed a reference to the parser object and a frame object; these should be used to parse wikitext.

has been around since version 1.8. Its advantages include simplicity (it takes just one argument and returns a string) and the fact that it parses extension tags in, so you can nest extension tags.

The second parameter to recursiveTagParse,, is an optional argument introduced in MW 1.16 alpha (r55682).


 * If  is provided (using the value of   passed to your extension), then any template parameters in   will be expanded.  In other words, content such as   will be recognized and converted into the appropriate value.
 * If  is not provided (e.g.,  ), or if   is set to false, then template parameters will not be expanded;   will not be altered.  Although this unlikely to be the desired behavior, this was the only option available before MW 1.16.

However, one step of parsing that is still skipped for tags, even when using recursiveTagParse, is Parser::preSaveTransform. preSaveTransform is the first step of parsing, responsible for making permanent changes to the about-to-be saved wikitext, such as:

The original call to preSaveTransform intentionally skips such conversions within all extension tags. If you need pre save transform to be done, you should consider using a parser function instead. All tag extensions can also be called as a parser function using  which will have pre save transform applied.
 * Converting signatures (, ~ ,  )
 * Expanding link labels, also known as the pipe-trick (e.g., changing Help:Contents into Contents ). Without this step, shorthand links such as Help:Contents are considered to be invalid, and are left in their wikitext form when parsed.
 * Expanding templates.

A partir de la versión 1.5
A partir de la versión 1.5, MediaWiki cuenta con soporte para parámetros (atributos de etiqueta) de tipo XML. The parameters are passed as the second parameter to the hook function, as an associative array. The value strings have already had HTML character entities decoded for you, so if you emit them back to HTML, don't forget to use, to avoid the risk of HTML injection.

How can I avoid modification of my extension's HTML output?
The return value of a tag extension is considered almost parsed text, which means its not treated as pure html, but still modified slightly. There are two main things that are done to the output of a tag extension (Along with a couple other minor things):


 * Replace strip markers. Strip markers are certain items which are inserted at various stages of processing wikitext to act as a marker to re-insert removed content at a later time. This is not something extensions usually need to worry about.
 * which turns *'s into lists, and turns any line starting with a leading space into a &lt;pre&gt; among other things. This can sometimes be an issue in some extensions.

Tag extensions also support returning an array instead of just a string (Much like parser functions) in order to change how the return value is interpreted. El valor de la posición 0 de la matriz debe ser el HTML. The "markerType" key can be set to  in order to stop further parsing. Doing something like  would ensure that the $html value is not further modified and treated as just plain html.

How do I get my extension to show up on Special:Version?
In order for your extension to be displayed on the MediaWiki Special:Version page, you must assign extension credits within the PHP code.

To do this, add a  variable as the first executable line of code before the hook line or function definition.

An example extension credit is:

Replace  with one of the following (unless your extension falls under multiple classes&mdash;then create a credit for each class):


 * 'specialpage'&mdash;reserved for additions to MediaWiki Special Pages;
 * 'parserhook'&mdash;used if your extension modifies, complements, or replaces the parser functions in MediaWiki;
 * 'variable'&mdash;extension that add multiple functionality to MediaWiki;
 * 'media'&mdash;used if your extension is a media handler of some sort
 * 'other'&mdash;all other extensions.

The  is the name of an interface/i18n message that describes your extension that will need to be defined in your extension's i18n.php file. If you omit this field, the  field will be used instead.

Retrieving the tag name inside of the callback
Suppose you have several tags  and   that share the same callback, and inside the callback function, you want to obtain the name of the tag that invoked the callback.

The short answer is: the tag name ( or  ) is not present in any of the callback's arguments. But you can work around this by dynamically constructing a separate callback for each tag:

Véase también

 * – Lista de etiquetas y variables especiales como,  , ...
 * – Lista de etiquetas del analizados en uso en los wikis de Wikimedia.
 * Project:Extension requests
 * Project:Extension requests
 * Project:Extension requests
 * Project:Extension requests
 * Project:Extension requests