Widgets

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The Widgets extension which is installed on Wiki Normal allows the creation of raw HTML pages that can be embedded (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.

This extension is maintained here: https://www.mediawiki.org/wiki/Extension:Widgets

And the widgets employed can be found here: http://www.mediawikiwidgets.org/Widgets_Catalog

Wiki Normal has installed the following:

  • Widget:Google Books
  • Widget:MediaWiki

Download

To get the code with Git, type the following commands:

<syntaxhighlight lang="bash"> cd extensions git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/Widgets.git cd Widgets git submodule init git submodule update </syntaxhighlight>

You can also download the code as a .zip file, here.

Installing

  1. Download the code archive, create a $IP/extensions/Widgets folder and unpack the archive into there. Note: $IP stands for the root directory of your MediaWiki installation, the same directory that holds LocalSettings.php.
  2. Download the latest Smarty release and unpack it into there, too.
  3. Create a folder smarty inside the Widgets folder.
  4. Move the folder libs from the unpacked Smarty archive into Widgets/smarty.

This puts everything into expected places. You can delete the remainings of the unpacked Smarty archive.

Configuration

To install this extension, add the following to LocalSettings.php: <syntaxhighlight lang="php"> require_once "$IP/extensions/Widgets/Widgets.php"; </syntaxhighlight>

Folder permissions

Also, the $IP/extensions/Widgets/compiled_templates/ 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.

An example of Qnap:

Start telnet with port22
find / -name 'compiled_templates' [cr]
[result] /share/MD0_DATA/Qweb/mediawiki-1.15.1/extensions/Widgets/compiled_templates
chmod a+rw /share/MD0_DATA/Qweb/mediawiki-1.15.1/extensions/Widgets/compiled_templates

Usage

To add a widget to your MediaWiki installation, just create a page in the Widget: namespace and then use the {{#widget:...}} parser function to include it in the pages of the wiki.

{{#widget}} parser function

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

{{#widget:WidgetName|param1=value1|param2=value2}}

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:

<a href="<!--{$param1|escape:'url'}-->"><!--{$param2|escape:'html'}--></a>

The escape options specifies how the parameter will be 'escaped', or encoded, in the resultant Widget. 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, which is automatically added to your wiki when you install this extension.

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 below for more info.

You can find many pre-defined widgets to install in your wiki at MediaWikiWidgets.org. If you're 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 foreach to go through the array.

Booleans (true/false)

Since version 0.8.5, this extension supports passing boolean parameters by just using a parameter name without a value, like this:

{{#widget:WidgetName|popup}}

This will set $popup to true for your widget. Also, in addition to PHP's default handling of boolean conversions, you can use value "false" to set the boolean value false (this is not the case in PHP as string "false" doesn't get converted to a boolean false; see PHP docs on boolean casting).

{{#widget:WidgetName|popup=false}}

Dotted notation

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

Example

Widget:AssocTest might look like this:

<includeonly><ul>
<!--{foreach from=$arg key=key item=item}-->
   <li><!--{$key|escape:'html'}-->: set to <!--{$item|escape:'html'}--></li>
<!--{/foreach}-->
</ul></includeonly>

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

{{#widget:AssocTest|arg.foo=bar|arg.bar=oni}}

..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 escape), the Widgets extension implements the validate modifier, that uses PHP Data filtering to allow for validating widget parameters.

To make sure the $homepage variable value is a valid URL, you can use following code:

<a href="<!--{$homepage|validate:url}-->">Homepage</a>

The following values for the validate are supported (mapping to PHP's validation filters):

  • url (FILTER_VALIDATE_URL)
  • int (FILTER_VALIDATE_INT)
  • boolean (FILTER_VALIDATE_BOOLEAN)
  • float (FILTER_VALIDATE_FLOAT)
  • email (FILTER_VALIDATE_EMAIL)
  • ip (FILTER_VALIDATE_IP)

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 {{#widget}} 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 purge 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).

Additional 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

As of version 0.9 you can use the FlaggedRevs extension to enable a widget security review process.

This will enable the Widgets extension to use only stable versions of the Widget:* pages.

When you have your FlaggedRevs configured in the way that represents your review process, just set the following variable in your LocalSettings.php: <source lang="php"> $wgWidgetsUseFlaggedRevs = true; </source>

This will tell the Widgets extension not to protect Widget:* pages using permissions, but rather require changes to be reviewed for security before they can take effect.

To just use FlaggedRevs to review widgets, the following configuration should suffice: <source lang="php"> require_once( "$IP/extensions/Widgets/Widgets.php" ); require_once( "$IP/extensions/FlaggedRevs/FlaggedRevs.php" );

$wgFlaggedRevsNamespaces = array(NS_WIDGET); $wgFlaggedRevTags = array(

       'security' => array( 'levels' => 1, 'quality' => 1, 'pristine' => 1 )

);

$wgFlaggedRevsOverride = true; $wgWidgetsUseFlaggedRevs = true; </source>

Changing the directory for storing the compiled widgets

Since version 1.1 the widgets extension provides a parameter allowing to change the directory for storing the compiled widgets ($compile_dir in the code). The default setting is <source lang="php" enclose="div"> $wgWidgetsCompileDir = "$IP/extensions/Widgets/compiled_templates/"; </source> If you change the location by setting the parameter with another directory, make sure that it exists and that it has the correct permissions.

Changing the namespace ID

The default ID for the "Widget:" namespace is 274. This can be changed if you want, but make sure that it's an even number. To set the namespace ID, define a value for NS_WIDGET before you include the extension in LocalSettings.php: <source lang="php"> define('NS_WIDGET', 274); require( "$IP/extensions/Widgets/Widgets.php" ); </source> The "Widget talk" namespace ID (NS_WIDGET_TALK) will be automatically defined as NS_WIDGET + 1, so don't set it yourself.

You can use NS_WIDGET and NS_WIDGET_TALK when configuring other MediaWiki properties.

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 editwidgets permission (the widgeteditor group is also created to add users to; see Help:User rights management for more details).

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

  • 1.2.1 (November 9, 2015) - Minor changes: improved debugging, license to show on "Special:Version"
  • 1.2 (April 29, 2015) - Possibility of arbitrary HTML output removed, support added for PHP 5.3
  • 1.1 (May 28, 2014) - i18n messages moved into JSON files, fixes for MediaWiki 1.21+, new parameter for setting the storage location of compiled widgets.
  • 1.0 (February 21, 2013) - Security leak fixed.
  • 0.10.1 (February 20, 2013) - Smarty added as a Git submodule, and updated to version 3.1.7.
  • 0.10.0 (January 19, 2012) - 'editwidgets' permission given to sysops by default, support removed for MediaWiki < 1.16.
  • 0.9.2 (January 12, 2011) - PHP fixes.
  • 0.9.1 (September 19, 2010) - Some code structure changes and fix to a bug 25219.
  • 0.9 (April 16, 2010) - Added support for FlaggedRev extension controlling Widget review.
  • 0.8.10 (November 27, 2009) - Security Release: Fixed a security hole in error message.
  • 0.8.9 (November 11, 2009) - Bugfix release: base64 wasn't identified properly which caused some widgets not to be displayed.
  • 0.8.8 (November 2, 2009) - HTML is inserted as-is, thanks to Joshua C. Lerner.
  • 0.8.7 (June 19, 2009) - namespaces issues and i18n issues fixed by ialex.
  • 0.8.6 (May 22, 2009) - some important security fixes by Tim Starling.
  • 0.8.5 (March 12, 2009) - Allowing parameters without values to work as bulean "true" and converting test "false" into boolean false (which is not the case in PHP itself).
  • 0.8.4 (March 11, 2009) - Minor security release - compiled Smarty templates can't be accessed directly. Also fixed a problem with compiled_templates being empty in archives and therefore not extractable by some software.
  • 0.8.3 (February 10, 2009) - Added 'validate' modifier that makes sure variable value conforms to validation rules (using http://us.php.net/filter).
  • 0.8.2 (January 27, 2009) - Fixed a bug when widgets were not showing up correctly on old versions of the pages. Thanks to Max Ingleton for a bug report.
  • 0.8.1 (June 25, 2008) - Worked around MediaWiki bug that inserts </p><p> in front of widget output.
  • 0.8 (June 10, 2008) - Fixed a bug where variables were carried over from one widget to another on the same page
  • 0.7 (May 23, 2008) - Added support for arrays and Smarty's dotted notation
  • 0.6 (May 9, 2008) - Minor tweaks and bug fixes, release Makefile
  • 0.5 (Feb 11, 2008) - First public release

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

Support

The best way to seek help with this extension is to send your questions to MediaWiki Widgets Google group

http://groups.google.com/group/mediawiki-widgets

The extension maintainer, and active users and contributors, are on this list and will be able to help you.

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:<your-widget-name>" /path-to-your-mediawiki/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
Error in widget Youtube: Unable to load template 'wiki:Youtube'
when the widget is called "Widget:YouTube", or vice versa.
  • If the page doesn't load and you see the following error message in the log file:
PHP Fatal error:  Smarty error: unable to write to $compile_dir '/path-to-your-mediawiki/extensions/Widgets/compiled_templates'.
Be sure $compile_dir is writable by the web server user. in /path-to-your-mediawiki/extensions/Widgets/smarty/Smarty.class.php on line 1095,
referer: http://your-wiki.com/Widget:<your-widget-name>
Check if you changed permissions for Smarty to store compiled templates in.
  • 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.

Video widgets

More widgets

Even more widgets

To get the most up-to-date list of widgets, click here.

Frequently asked questions

How do I get a video to align to the right with the other images?

Use something like this. Note that the <br> 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. <source lang="html5">


Seeing bad acting sully a good

script can trigger some people
who place a high value on
natural-seeming
performances.

</source>