Wikipedia Preview

Wikipedia Preview is a JavaScript component that allows you to provide context from Wikipedia about words or phrases on any website. It lets you show a popup card with a short summary from Wikipedia when a reader hovers over a link.

Tasks and issues are tracked on Phabricator.

Desktop	Mobile	Dark mode	Fullscreen gallery

Storybook: https://wikimedia.github.io/wikipedia-preview/main/storybook

Compatibility

Browsers	Versions
Chrome, Firefox, Opera, Edge	Current and previous version
Internet Explorer	11+
Safari	5.1+
iOS	6.1+
Android	4.1+

Features

• Works with any link that has an article on Wikipedia
• Supports LTR and RTL languages
• Works for articles with or without a lead image

Getting Started

Integrating Wikipedia Preview to your site consists of a three-step process:

1. Loading wikipedia-preview.js (as a standalone script, WordPress plugin, or an npm dependency)
2. Invoking wikipediaPreview.init( <options> )
3. Annotating articles accordingly

You can read more about each step below. Once Wikipedia Preview is set up correctly, you should see the version information being logged in your JS console. You can also invoke wikipediaPreview.version() from your JS console to view version information at any time.

WordPress Plugin

A WordPress plugin providing a thin wrapper around Wikipedia Preview to simplify its integration and usage within WordPress is available on GitHub and WordPress.org.

Standalone Script

<script src="wikipedia-preview.umd.cjs"></script>
<script type="text/javascript">
  wikipediaPreview.init()
</script>

You can serve the file yourself or include it from unpkg (The library version 1.9.0 and later cannot be loaded from Unpkg due to a MIME type mismatch issue, the current workaround solution is adding the ?module parameter to get the correct content-type).

NPM

$ npm install wikipedia-preview --save

const wikipediaPreview = require('wikipedia-preview')
wikipediaPreview.init()

Options of the init function

The init function accepts the following options:

Name	Type	Default	Description
root	string,Element,Element[]	document	Where to look for elements that should have the popup selector. Can be a selector to locate the root, a DOM Element, or an array of Elements
selector	string	'[data-wikipedia-preview]'	How nodes that should have the popup are identified
lang	string	'en'	Default Wikipedia language
popupContainer	string,Element	document.body	Where to put the popup in the DOM. Can be a selector or a DOM element.
detectLinks	Boolean	false	Allow Wikipedia hyperlinks to have the popup
events	Object	{}	Custom event handlers: { onShow: <fn>, onWikiRead: <fn> }
debug	Boolean	false	Shows the debug message when init() is called
prefersColorScheme	string	'detect'	Sets theme color. Allowed values are 'light', 'dark' and 'detect'. Setting it to 'light' or 'dark' will dictate theme color regardless of prefers-color-scheme; setting to 'detect' will render preview according to prefers-color-scheme.

Example (custom selector)

<p class="content">
	You can learn about <span class="wiki">Chat</span> and <span class="wiki">Chien</span> from Wikipedia.
</p>
<div class="popup-container"></div>

wikipediaPreview.init({
	root: document.querySelector('.content'),
	selector: '.wiki',
	popupContainer: '.popup-container',
	lang: 'fr'
});

Example (detect Wikipedia links)

<p class="content">
	You can learn about <a href="https://en.wikipedia.org/wiki/Chat">Chat</a> and <a href="https://en.wikipedia.org/wiki/Chien">Chien</a> from Wikipedia.
</p>

wikipediaPreview.init({
	detectLinks: true
});

Example (custom event handlers)

wikipediaPreview.init({
	events: {
		onShow: function(title, lang, type) {
			// call custom instrumentation here
		},
		onWikiRead: function(title, lang) {
			// call custom instrumentation here
		}
	}
});

Attributes

data-wikipedia-preview

To indicate that a word or expression should bring up the article preview popup, mark it with the data-wikipedia-preview attribute (or anything else as long as you're using the selector option described above).

data-wp-title

When the article title is not the same as the node's textContent property, use the data-wp-title attribute to specify the article title.

Note that the article title can include a section id. For example: Europe#Classical_antiquity

data-wp-lang

To use a language different than the language specified in the options, use the data-wp-lang attribute.

.wmf-wp-with-preview

To use the default trigger link styling:

• Add the following link to the page header:

<link href="wikipedia-preview-link.css" rel="stylesheet">

• Add the class wmf-wp-with-preview to the node

If you prefer to style them in a way that makes more sense for your context, simply don't include the wikipedia-preview-link.css link in the header and add your own class to the node. Both of these are valid ways:

[data-wikipedia-preview] {
	background-color: yellow;
}

.my-own-css-style {
	background-color: yellow;
}

CSS custom properties

If you wish to adjust the styling of the light/dark theme, you can override the following CSS custom properties to your liking as shown below, under the appropriate prefers-color-scheme query.

@media (prefers-color-scheme: dark) {
	.wikipediapreview {
		--wikipediapreview-primary-background-color: #202122;
		--wikipediapreview-secondary-background-color: #202122;
		--wikipediapreview-primary-color: #eaecf0;
		--wikipediapreview-filter-setting: invert(1);
	}
}

Acknowledgements/Contributors

This is heavily inspired by jquery.wikilookup and Page Previews.