Archiving the Mobile Web

Frank McCown, Monica Yarbrough, & Keith Enlow

Computer Science DeptHarding University

WADL 2013Indianapolis, IN

July 25, 2013

Mobile vs. Stationary Web

Mobile Web-Related Markup Languages

http://en.wikipedia.org/wiki/File:Mobile_Web_Standards_Evolution_Vector.svg

Smartphone era

Two Types of Mobile Web

Feature Phone Web Smartphone Web

cHTML (iMode), WML, WAP, etc.

XHTML, HTML5, etc.

Serving Up Mobile Sites

1. Responsive web design• Same HTML content to desktop and mobile

• CSS media queries alter appearance

<!-- CSS media query on a link element --><link rel="stylesheet" media="(max-width: 800px)" href="example.css" />

<!-- CSS media query within a style sheet --><style>@media (max-width: 600px) {.sidebar { display: none; }

}</style>

Example of Responsive Web Design

Serving Up Mobile Sites

1. Responsive web design• Same HTML content to desktop and mobile

• CSS media queries alter appearance

2. Redirect mobile user agent to mobile site• Client-side redirection

• Server-side redirection

Client-Side Redirection

• JavaScript detects mobile user agent

// From www.harding.eduvar ua = navigator.userAgent.toLowerCase(); if (queryString.match('version=mobile') ||

ua.match(/IEMobile|Windows CE|NetFront|PlayStation|like Mac OS Z|MIDP|UP\.Browser|Symbian|

Nintendo|BlackBerry|mobile/i)) {

if (!ua.match('ipad')) {if (window.location.pathname.match('.html'))

window.location = window.location.pathname.replace('.html', '.m.html');else

window.location = window.location.pathname + 'index.m.html'; }

}

Client-Side Redirection

Server-Side Redirection

• Server routes mobile user agent to different page

Apache Example:RewriteEngine OnRewriteBase /

RewriteCond %{HTTP_USER_AGENT} (android|bb\d+|meego).+mobile|avantgo|badda\/|blackberry|blazer|etc…|zte\-) [NC]RewriteRule ^$ http://detectmobilebrowser.com/mobile [R,L]

https://developers.google.com/webmasters/smartphone-sites/details

Server-Side Redirection

Serving Up Mobile Sites

1. Responsive web design• Same HTML content to desktop and mobile

• CSS media queries alter appearance

2. Redirect mobile user agent to mobile site• Client-side redirection

• Server-side redirection

3. User-agent content negotiation• Dynamically serving different HTML for the same URL

User-Agent Content Negotiation

• Server serves up different content for same URL

• Use Vary: User-Agent header in response

• Best method for serving content quickly

Archiving Mobile Sites

1. Responsive web design• Easy: Crawl like normal

• Use client tools to view page formatted for mobile

2. Redirect mobile user agent to mobile site• Need to crawl with mobile user agent

• Need JavaScript-enabled crawler to handle client-side redirection

3. User-agent content negotiation• Need to crawl with mobile user agent

• Need to distinguish mobile vs. desktop for same URL

How are we doing archiving mobile sites so

far?

Earliest archived

page

Earliest 2007 archived page: WML

Finally some news!

Really???

Great…

Only desktop version is archived!

Mobile FinderBy Monica Yarbrough

Google’s Suggestions for SEO

• Vary HTTP Header

• Annotations within the HTML:• On desktop page:

• <link rel=“alternate” media=“only screen and (max-width: 640px)” href=“http://m.example.com/page-1” >

• On mobile page:• <link rel=“canonical” href=“http://www.example.com/page-1”

>

• Media queries

https://developers.google.com/webmasters/smartphone-sites/

How Mobile Finder Works

• Use both desktop and mobile useragents

• Look for:• Redirect

• Different content

• Different stylesheets

• Media queries

How Mobile Finder Works

• Change the url to fit common mobile url patterns

ex: www.t-mobile.com m.t-mobile.com

PhantomJs

• Headless WebKit (browser)

• Well-known and widely used

• Used to get the content of a page

• Takes snapshots of the sites it visits

• Scriptable with coffeescript or javascript

Web Service

• Query string with 2 parameters• url (required)

• useragent (optional)

• http://cs.harding.edu/mobilefinder/service.php?url=URL&useragent=USER_AGENT

• Default useragent = Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_1 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8B117 Safari/6531.22.7 (compatible; mediaqueries/1.0; +http://cs.harding.edu)

Results

<MobileFinder>

<url>http://www.cnn.com/</url>

<mobileUrl>http://www.cnn.com/</mobileUrl>

<reason>

<code>400</code>

<message>differing content</message>

</reason>

<useragent> Mozilla/5.0 (Android; Linux armv7l; rv:9.0) Gecko/20111216 Firefox/9.0 Fennec/9.0</useragent>

<timeAccessed>2013-07-20 15:23:42</timeAccessed>

<error/>

<MobileFinder/>

Limitations

• Crashing

• Inconsistent results

• Problems executing javascript redirection

• Falsely fails when it actually gets the content

• Fails to get url of page accessed

• Slow

Limitations

• Client-side Redirects

www.golferen.no/wip4/ (right)

www.ng.kz/ (below)

Analysis Results

• Accuracy (of 100 random hand-checked results)• 96 % accurate overall

• 1 % inaccurately record not found when there is in fact a mobile version

• 3 % inaccurately say mobile found when there is not a mobile version

Nytimes desktop vs mobile

Rakuten.co.jpdesktop vs mobile

Are Google’s Suggestions Used?

• 28 % found a mobile version following Google’s suggestions

• 85 % found as having some sort of mobile version

Are Google’s Suggestions Used?

• 28 % found following Google’s suggestions

• Of the 82% that were found as not following the rules:

• 93% missing vary HTTP header

• 89% missing alternate and canonical links

Are Google’s Suggestions Used?

• 28 % found following Google’s suggestions

• 85 % found as having some sort of mobile version• Redirect: 35%

• “Significantly” different content: 28%

• Stylesheets alone: 9%

• Stylesheets and media queries: 11%

• Media queries alone: 6%

• Differing urls (trial and error): 11%

End Result

• As a whole, mobile web pages do not adhere to Google’s standards

• There are no truly consistent ways for finding a mobile version of a site

Keith Enlow

Heritrix Mobile

Introduction

• Heritrix 3.1

• Mobile Finder Web Service

• 2 Options• Crawl desktop web pages (default)

• Crawl mobile web pages using Mobile finder and exclude mobile web pages that use media queries.

Experiment

• Decision Making Heritrix

• Web Service (Mobile Finder) Heritrix• Modified Heritrix 3.1 to include two options for crawling

• Option 0: Crawl with desktop user agent

• Option 1: Crawl with mobile user agent using Mobile Finder

• Added built in mobile user agent adapted from Google Bot

• Crawled a small set of URLs

• Used Mobile Finder to find if the given URL has mobile version

• Wrote a small script to discover differences between the mobile and desktop versions

<property name="userAgentTemplate"

value="Mozilla/5.0 (compatible; heritrix/@VERISON@+ @OPERATOR_CONTACT_URL@)"/>

<property name="userAgentTemplateMobile"

value="Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_1 like Mac OS X; en-us)

AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8B117

Safari/6531.22.7 (compatible; heritrix/@VERSION@+ @OPERATOR_CONTACT_URL@"/>

<!-- Option # = Description

0 [Default] Crawl using desktop user agent

1 Crawl using mobile user agent + Mobile Finder Web Service -->

<property name="CrawlOption" value="0" />

URLs Crawled

Desktop URL Mobile URL

• www.huffingtonpost.com• www.foxnews.com• www.nbcnews.com• www.whitehouse.gov• www.nasa.gov• www.ssa.gov• www.cornell.edu• www.stanford.edu• www.mit.edu

• m.huffpost.com • foxnews.mobi• www.nbcnews.com• m.whitehouse.gov• mobile.nasa.gov• www.ssa.gov/mobile• m.cornell.edu/#home• m.stanford.edu• m.mit.edu /

mobile.mit.edu

Redirection/Delivery

• 200 Response (server side redirect)

• 302 “Temporary” relocation

• 301 “Permanent” relocation

• JavaScript Redirection (client side redirect)

• Media Queries

• Style Sheets

Tiny Limits

• No JavaScript Engine• Heritrix is unable to perform and execute JavaScript

code

• Unable to catch client side redirection and will instead continue to crawl the desktop version of the web page.

Note: The Mobile Finder Web Service will find the mobile page and therefore Heritrix will continue the crawl.

• www.nasa.gov

• www.ssa.gov

• www.cornell.edu

Hufington Fox News NBC News NASA SSA White House Stanford Cornell MIT

56774 12703 8894 4960 2380 8121 2351 2901 120

2134 110 3545 63 53 570 116 94 124

Total Link Count

HTML Distribution

Huffington Fox News NBC News NASA SSA White House Stanford Cornell MIT

11550 2681 2302 851 20 3251 385 596 12

493 35 488 18 0 76 16 31 26

JavaScript Distribution

Huffington Fox News NBC News NASA SSA White House Stanford Cornell MIT

245 107 46 589 12 83 104 525 2

33 4 14 8 0 13 4 8 0

CSS Distribution

Huffington Fox News NBC News NASA SSA White House Stanford Cornell MIT

587 301 72 304 1 154 214 86 3

36 3 17 1 0 19 8 4 3

Image Distribution

Huffington Fox News NBC NASA SSAWhite House Stanford Cornell MIT

38671 8893 5852 2908 17 4187 1460 1484 87

1227 59 2769 28 0 436 74 4 89

Acknowledgements

• Internet Archive aided in Mobile Finder work

• Funded by NSF grant 1008492