Timeline

• Copyright (c) 2013 The Wellcome Library
• License: MIT
• Uses: jQuery, jQueryUI, moment, iScroll, jQuery Address, easyXDM, json2

The timeline can be seen in action here

The aim of the project was to provide a reusable presentation mechanism that was easily integrated into the Wellcome Library’s content management system and other data sources. The timeline can be embedded on any page, much like a YouTube video. Instead of a video file it loads a chunk of data in JSON format that provides it with text and graphics for all the events it needs to render. Anyone who can provide a file in this format can use the timeline to render their own events.

In this example the JSON is generated from a CMS – but it could come from any data source, or even be hand-crafted. Here is an example of the same timeline component loading JSON data generated from a SPARQL query to DBpedia:

The timeline shows more events as you zoom in, smoothly expanding the canvas until there is enough room for the chosen event.

Embedding

You will notice that the Example Timeline has an 'embed' option in the bottom-left corner.

You can use the code in this panel to embed the timeline on your own website, e.g:

<div class="timeline" data-uri="/content/timelines/history-of-genetics-timeline/" data-eventid="" style="width:600px; height:600px; background-color: #000"></div>
<script type="text/javascript" src="http://wellcomelibrary.org/plugins/timeline/embed.min.js"></script><script type="text/javascript">/* wordpress fix */</script>

The timeline also supports 'deep linking' to events, where a hash value is appended to the Url as you browse e.g:

http://wellcomelibrary.org/.../genetics-timeline/#16121

##Developers

The timeline project uses a build.ps1 PowerShell script in the root of the project to combine and minify the various JavaScript files into embed.min.js and wellcomeTimeline.min.js, (right click > Run with PowerShell). You will need Google Closure Compiler - and a Java runtime - and will need to edit the build.ps1 file to point to it).

• embed.min.js - creates an iframe within div.timeline to host timeline.html.
• wellcomeTimeline.min.js - contains all the jQueryUI widgets used to create the user interface, plus a few utility scripts.

To get the project running on localhost, create a website pointing to the /src directory with a virtual directory called 'build' pointing to the /build directory.

Alternatively, to run with Visual Studio's built-in web server 'Cassini' open the /src directory as a Web Site and change the solution's Virtual Path in the properties panel to /. It is not possible to create a virtual directory to /build with Cassini, so follow the steps in the next paragraph to use the unminified scripts.

To debug individual scripts, open timeline.html, comment out wellcomeTimeline.min.js and uncomment the scripts directly underneath. Also open index.html and change the src of the script tag from build/embed.min.js to js/embed.js

Data Format

The example timeline data employs the use of Julian days. These are useful for plotting applications as they represent a calendar-independent, absolute unit of time.

However, the code controlling the main user interface only deals in moment objects.

The timeline loosely employs the Provider Model, which abstracts the date parsing out to wellcomeTimelineProvider.js.

Providers could be created to work with any arbitrary date format that can be converted to moment objects.

To change the provider, edit the provider option of the wellcomeTimeline widget in timeline.html.

Use the data-uri attribute of div.timeline to set the path to your custom data source.

Notes

The /* wordpress fix */ empty script in the embed code is for convenience when using the Wordpress WYSIWYG editor, which will otherwise strip out the script tags.