Reconstructing the past with MediaWiki:

Programmatic Issues and Solutions

Shawn M. Jonessjone@cs.odu.edu

Old Dominion University

Reconstructing the Past with the Internet Archive

HTML

Images

JavaScript

CSS

Our goal: Temporal CoherenceMake the page look as it looked at the time it was archived.

Some Results from the Internet Archive Are Lacking

Images change between the time the Archive crawls the main page and the time it gets to the images

Sometimes embedded images are missing when the Archive gets to them

Sometimes the page is designed for a specific browser in mind

Image from “A Framework for Evaluation of Composite Memento Temporal Coherence” by S. Ainsworth, M. L. Nelson, H. Van de Sompel. http://arxiv.org/abs/1402.0928

MediaWiki Shouldn’t Have This Problem

HTML Images

JavaScript

CSS

What we’re not doing

Interest in Reconstructing the Past With MediaWiki

Simplified Memento Overview

Rules for Reconstructing the Past With MediaWiki

Do not modify any existing MediaWiki code!

Conform to MediaWiki coding standards

And…

Reconstructing the Past

Articles

Templates

Embedded Images

Embedded JavaScript

Embedded CSS

Accessing Old Article Text

The oldid argument references a revision of a page within MediaWiki's database

Merely visiting the URI with the oldid will give you the text content of the page as it existed at that revision

Reconstructing the Past

ArticlesHandled by Memento MediaWiki Extension

Templates

Embedded Images

Embedded JavaScript

Embedded CSS

Including the Right Template

This gives us:$title - the Title object for the given page$parser - the Parser object for the given page$id - the revision ID (oldid) for the Template page

Using $parser, and $title, we can change the $id and fetch an old revision of the Template

Reconstructing the Past

ArticlesHandled by Memento MediaWiki Extension

TemplatesHandled by Memento MediaWiki Extension

Embedded Images

Embedded JavaScript

Embedded CSS

But What About Images?

This Map is important to understanding the content of this article

This image is changed as the article is changed, to reflect its content

It’s the same map if we look at the June 6, 2013 revision now

Users can't view this embedded resource as it looked on June 2013 while reading the article from that time period

What should have happenedThis is the the map from June, 2013 that should have been displayed

This is the current map

The content of the article won't match the data in this visual aide, possibly confusing a user who wanted historical information on this topic

We Tried To Solve This

Upon further inspection of the code in MediaWiki, the $time argument from this function is never used as detailed here

We Just Solved This

Upon further inspection of the code in MediaWiki, the $file argument’s getHistory() function can be used to acquire previous revisions of images

Reconstructing the Past

ArticlesHandled by Memento MediaWiki Extension

TemplatesHandled by Memento MediaWiki Extension

Embedded ImagesPrototyped for future version ofMemento MediaWiki Extension

Embedded JavaScript

Embedded CSS

What about CSS/JavaScript?

The present CSS of this page conflicts with the past Template.

We Couldn’t Solve This

The data is present, but we could not find any way for an extension to access or render it.

Recap on Reconstructing the Past

ArticlesHandled by Memento MediaWiki Extension

TemplatesHandled by Memento MediaWiki Extension

Embedded ImagesPrototyped for future version ofMemento MediaWiki Extension

Embedded JavaScriptRequires changes to MediaWiki

Embedded CSSRequires changes to MediaWiki

Uniform solution

• RFC 7089, Memento, was designed to provide uniform access to past versions of all resources on the Web

• Memento provides a web standard to access these resources

Resources• Memento Protocol: http://tools.ietf.org/html/rfc7089• Memento Website: http://www.mementoweb.org/• Memento MediaWiki Extension:

http://www.mediawiki.org/wiki/Extension:Memento• Memento Chrome Extension:

http://bit.ly/memento-for-chrome

• More details:http://ws-dl.blogspot.com/2014/04/2014-04-01-yesterdays-wiki-page-todays.html

• Contact me: sjone@cs.odu.edu

Backup Slides

Sample URI-R (Step 1) HTTP Response

HTTP/1.1 200 OKDate: Sun, 25 May 2014 21:39:02 GMTServer: ApacheX-Content-Type-Options: nosniffLink: http://ws-dl-05.cs.odu.edu/demo/index.php/Daenerys\_Targaryen; rel="original latest-version",

http://ws-dl-05.cs.odu.edu/demo/index.php/Special:TimeGate/Daenerys\_Targaryen; rel="timegate",

http://ws-dl-05.cs.odu.edu/demo/index.php/Special:TimeMap/Daenerys\_Targaryen; rel="timemap”; type="application/link-format”Content-language: enVary: Accept-Encoding,CookieCache-Control: s-maxage=18000, must-revalidate, max-age=0Last-Modified: Sat, 17 May 2014 16:48:28 GMTConnection: closeContent-Type: text/html; charset=UTF-8

Sample URI-G (Step 2) HTTP Response

HTTP/1.1 302 FoundDate: Sun, 25 May 2014 21:43:08 GMTServer: ApacheX-Content-Type-Options: nosniffVary: Accept-Encoding, Accept-DatetimeLocation: http://ws-dl-05.cs.odu.edu/demo/index.php?title=Daenerys_Targaryen&oldid=1499Link: <http://ws-dl-05.cs.odu.edu/demo/index.php/Special:TimeMap/Daenerys_Targaryen>; rel="timemap”; type="application/link-format",

<http://ws-dl-05.cs.odu.edu/demo/index.php/Daenerys_Targaryen>; rel="original latest-version”Connection: closeContent-Type: text/html; charset=UTF-8

Sample URI-M (Step 3) HTTP Response

HTTP/1.1 200 OKDate: Sun, 25 May 2014 21:46:12 GMTServer: ApacheX-Content-Type-Options: nosniffMemento-Datetime: Sun, 22 Apr 2007 15:01:20 GMTLink: <http://ws-dl-05.cs.odu.edu/demo/index.php/Daenerys_Targaryen>; rel="original latest-version”,

<http://ws-dl-05.cs.odu.edu/demo/index.php/Special:TimeGate/Daenerys_Targaryen>; rel="timegate”,

<http://ws-dl-05.cs.odu.edu/demo/index.php/Special:TimeMap/Daenerys_Targaryen>; rel="timemap”; type="application/link-format”Content-language: enVary: Accept-Encoding,CookieExpires: Thu, 01 Jan 1970 00:00:00 GMTCache-Control: private, must-revalidate, max-age=0Connection: closeContent-Type: text/html; charset=UTF-8