Extension:Widgets/en

The Widgets extension allows the creation of raw HTML pages that can be transcluded (similarly to templates) in normal wiki pages. You do this by creating pages in the Widget namespace. They avoid the security problems of raw HTML in editable wiki pages because the privilege to edit in the Widget namespace is managed. Many pre-written Widgets are available.

Download
To get the code with Git, type the following commands: Composer is a PHP dependency manager. For MediaWiki >= 1.35.2, you may need to update composer to version 2. Instructions here.

Installation
To invoke this extension, add the following to :

Also, the  folder should be made writable by the web server. See Making a directory writable by the webserver. The compiled templates folder is where Smarty stores pre-compiled templates.
 * Folder permissions

Configuration
The steps in this section are optional—the extension should work fine even without these changes, but they will give you more flexibility if you have a complex MediaWiki installation.

Using FlaggedRevs for widget review
You can use the FlaggedRevs extension to enable a widget security review process. See this version of the documenation. for how to integrate the extension.

Changing the directory for storing the compiled widgets
You can use the  variable to change the directory for storing the compiled widgets ($compile_dir in the code). The default setting is

If you change the location by setting the parameter with another directory, make sure that it exists and has the correct permissions.

User rights
This extension adds a namespace called "Widget", but due to potential security implications that can result from using insecure widget code, this namespace is only editable by users who have the  permission (the   group is also created to add users to; see Help:User rights management for more details).

Usage
To add a widget to your MediaWiki installation, just create a page in the Widget: namespace. You can then use the  parser function to include it in any page in the wiki.

parser function
To add a defined widget to pages, users can use the  parser function. The syntax is as follows:

Where WidgetName is a page name in the Widget namespace (e.g. Widget:WidgetName) and param=value pairs are the settable parameters, defined within the widget code.

Parameters can be expanded inside a widget using Smarty syntax, as follows:

The  options specifies how the parameter will be 'escaped', or encoded, in the resultant Widget. It is critically important that all parameters are escaped to prevent cross-site scripting vulnerabilities. Some escape methods are ineffective. In general you should use one of,  ,   or. See http://www.smarty.net/docsv2/en/language.modifier.escape for more information on this.

Pages in Widget namespace
All widgets in the wiki are defined by creating pages in the special "Widget:" namespace, like e.g. "Widget:WidgetName".

To see all Widgets defined in your system, you can simply go to the page "Special:AllPages", select "Widget" in the namespace dropdown and click "Go".

For security reasons, these pages are only editable by wiki administrators - see User rights above for more info.

You can find many pre-defined widgets to install in your wiki at MediaWikiWidgets.org. If you are interested in creating widgets yourself, see the next section.

Widget page syntax
The Widgets extension uses the Smarty PHP templating engine to provide simple templating functionality within widget pages. All parameters passed to a widget are converted into Smarty parameters.

Important: Use escape modifiers on all passed-in parameters to prevent users from passing in raw HTML from normal wiki pages. Failure to protect against this will expose the hosting site to XSS (and other) attacks.

Arrays
If you use the same parameter multiple times, the widget will get an array of values. You can use to go through the array.

Booleans (true/false)
In addition to PHP's default handling of Boolean conversions, you can (unlike in PHP) use the values "true" or "false" to set the Boolean value. The following would set the  parameter to , for example:

In addition, you can set Boolean parameters to  by just using a parameter name without a value, like this:

Dotted notation
Parameter names can have dots, and Smarty will interpret them as associative arrays, so you can use with both   and   attributes to traverse through them, or you can just use the same name with dots if you want to reference the parameter directly.

Widget:AssocTest might look like this:
 * Example

...and you might call this Widget as follows:

..which would be displayed as:
 * foo set to bar
 * bar set to oni

Validate modifier
In addition to standard Smarty modifiers (like the heavily used ), the Widgets extension implements the   modifier, that uses PHP Data filtering to allow for validating widget parameters. Validating a parameter is not a replacement for escaping a parameter. You should still use an escape modifier even when validating.The following values for the validate are supported (mapping to PHP's validation filters):


 * &mdash; Validate as url. Staring in Widgets 1.4.2 this uses MediaWiki's url validation instead of PHP's validation. This only allows url schemes listed in $wgUrlProtocols and unlike PHP validation does not allow urls with characters dangerous in HTML. Prior to Widgets 1.4.2 this used PHP's FILTER_VALIDATE_URL which is much less strict.
 * (FILTER_VALIDATE_URL) &mdash; Warning: Validating as a URL still allows JavaScript URLs that can lead to XSS. It also allows urls containing characters that are unsafe in HTML.
 * (FILTER_VALIDATE_INT) &mdash; Validates value as integer, optionally from the specified range, and converts to int on success.
 * or  (FILTER_VALIDATE_BOOLEAN)  &mdash; Returns   for "1", "true", "on" and "yes". Returns   otherwise.
 * (FILTER_VALIDATE_FLOAT) &mdash; Validates value as float, optionally from the specified range, and converts to float on success.
 * (FILTER_VALIDATE_EMAIL) &mdash; Warning: Valid email address can still contain characters that are unsafe in HTML, be sure to escape in addition to validating
 * (FILTER_VALIDATE_IP) &mdash; Validates value as IP address, optionally only IPv4 or IPv6 or not from private or reserved ranges.
 * (FILTER_VALIDATE_DOMAIN) &mdash; Warning: Valid domains can still contain characters that are unsafe in HTML, be sure to escape in addition to validating.
 * (FILTER_VALIDATE_MAC) &mdash; Validates value as MAC address.

Refreshing a widget page
If you're using a call to the widget within the widget page itself, then you will not see the updated widget (and no widget at all when you just created a page). This happens because the page contents are not available to the Widgets extension until a page is saved, but the call to the  parser function is made before the page is saved. After the page is saved, it's cached by MediaWiki, so you won't see the result even if you reload the page via the browser. To make the latest edits to the widget code appear, you need to refresh the page in the cache; to do this, you just need to use the  action (see also Purge extension), or wait a certain amount of time (up to 24 hours).

Widgets and templates
Placing widgets within templates makes them an invaluable tool for creating complex displays of data with minimal lines of code.

It is particularly helpful if you want to preset some parameters of the widget while allowing users to modify others (e.g. video ID for the YouTube widget or username for the Twitter widget).

Authors
The widgets extension was created and designed by Sergey Chernyshev. It is currently maintained by Yaron Koren, who has also contributed to the code base.

Other important contributions have been provided by Alexandre Emsenhuber, Jeroen De Dauw, Joshua Lerner, Majr, Sam Reed and Tim Starling.

Version history
The Widgets extension is currently at version 1.4.2. See the entire version history.

Contributing Widgets
If you created a widget and would like to share it, feel free to post it to MediaWikiWidgets.org website and to add a reference to it to the Widget library on this page.

Bugs and feature requests
If you found a problem, would like to contribute a patch or request a new feature, feel free to open a bug in the Wikimedia bug tracker:

https://phabricator.wikimedia.org/maniphest/task/create/?projects=MediaWiki-extensions-Widgets

Troubleshooting
There are a few common problems that users encounter when they start to use Widgets extension - we'll try to document them here:


 * On a widget page, right after you just created it (or copied from MediaWikiWidgets.org) you see the message:

Warning: Smarty error: unable to read resource: "Widget:" /../extensions/Widgets/ smarty/Smarty.class.php on line 1095


 * This is most likely caused by the widget not yet existing at the moment when the widget page itself is being processed - to solve this simply purge the page, e.g. add &action=purge (or ?action=purge if you have nice URLs) to the URL.
 * It's also possible that you called the Widget incorrectly. Widget page names are case sensitive and must match the name of the widget you're calling. E.g. don't use when the widget is called "Widget:YouTube", or vice versa.

PHP Fatal error: Smarty error: unable to write to $compile_dir '/../extensions/Widgets/compiled_templates'. Be sure $compile_dir is writable by the web server user. in /../extensions/Widgets/smarty/Smarty.class.php on line 1095, referer: https://your-wiki.com/Widget:
 * If the page doesn't load and you see the following error message in the log file:
 * Check if you changed permissions and owner for Smarty to store compiled templates in. See also this post for further details.


 * If your wiki began returning totally white pages or 500 errors when you updated MediaWiki to 1.20 or a later version, try setting the permissions on /../extensions/Widgets/compiled_templates to 777.

Widget library
MediaWikiWidgets.org contains a full library of ready-made widgets, including support for most of the major video sites. Any widget can be used simply by copying over the contents of the page.

To get the most up-to-date list of widgets by purpose, e.g. social media, video, images, etc. click here.

Extensions that can be replaced with widgets
Let's collect a list of extensions that can be replaced with widgets because all they do is output some HTML/JS/CSS with parameters and simple logic that can be done using Smarty templates.

Maybe someone will come and create a widget for that to simplify deployment. Also, these lists of extensions are a good source for action:

Frequently asked questions
Use something like this. Note that the line break tags will have to be added manually. 180px is used for width because that is the default for thumbnails. 150px is used for height because that keeps the same ratio as for the default 350x420.
 * How do I get a video to align to the right with the other images?