Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Avoiding Zombies in Archival Replay Using ServiceWorker

1,610 views

Published on

Live-leakage (zombie resource) is an issue in archival replay of web pages. This work proposes a mechanism to avoid such live-leakage using ServiceWorker. This work was presented in WADL 2017 on June 22 in Toronto, Ontario, Canada.

Published in: Science
  • Be the first to comment

  • Be the first to like this

Avoiding Zombies in Archival Replay Using ServiceWorker

  1. 1. Avoiding Zombies in Archival Replay Using ServiceWorker Sawood Alam, Mat Kelly, Michele C. Weigle, and Michael L. Nelson Web Science and Digital Libraries Research Group Old Dominion University, Norfolk, VA, 23529 @ibnesayeed @WebSciDL Supported in part by NSF III 1526700 1 WADL 2017, June 22-23, 2017, Toronto, Ontario, Canada
  2. 2. Sawood Alam <@ibnesayeed> 2008 Memento Seen in 2017 2 ● https://ws-dl.blogspot.com/2015/12/2015-12-08-evaluating-temporal.html ?
  3. 3. Sawood Alam <@ibnesayeed> 2008 Memento Seen in 2012 3 ● http://ws-dl.blogspot.com/2012/10/2012-10-10-zombies-in-archives.html
  4. 4. Sawood Alam <@ibnesayeed> XenLand @ Alpha Centauri 4
  5. 5. Sawood Alam <@ibnesayeed> Zombies in Archive 5 ?
  6. 6. Sawood Alam <@ibnesayeed> Zombies in Archive 6 <img src="http://xenland.alpha/images/map.png"> // Is rewritten on replay to become: <img src="http://archive.example.org/1998/http://xenland.alpha/images/map.png"> // URLs constructed by JavaScript are harder to rewrite on replay, e.g.: var base = 'http://xenland.alpha'; var imgdir = '/images/'; var img = document.createElement('img'); img.src = base + imgdir + 'ruler.png'; document.getElementById('ruler').appendChild(img); //=>> http://xenland.alpha/images/ruler.png
  7. 7. Sawood Alam <@ibnesayeed> Replay URL Resolution & Rewriting 7 Reference type Example Resolution after relocation Relative path images/logo.png Potentially correct Absolute path /public/images/logo.png Potentially incorrect Absolute URL http://example.com/public/images/logo.png Potentially live leakage http://example.com/public/index.html ... <img src="/public/images/logo.png"> ... http://archive.example.org/<datetime>/http://example.com/public/index.html ... <img src="/<datetime>/http://example.com/public/images/logo.png"> ...
  8. 8. Sawood Alam <@ibnesayeed> Avoiding Zombies ● Ahead-of-time rendering and JS execution ○ http://archive.is/ ● Archival replay proxy ○ https://github.com/ikreymer/pywb/wiki/Pywb-Proxy-Mode-Usage ● Browser extension ○ MementoFox (deprecated) ● JS override ○ wombat.js in PyWB ● ServiceWorker 8
  9. 9. Sawood Alam <@ibnesayeed> ● New web API (still a working draft) ● A standalone JavaScript file ● Persists in the browser independent of the window ● Acts as a proxy ● Installed by a web page under its domain at a specific path (called scope) ● Intercepts all requests in scope ○ Resources under the scope path (at any depth) ○ Secondary resource requests originated from any resource under scope ● Allows modification in request and response ● Primarily used in web applications for offline access and notification support ● Requires HTTPS ● Growing browser support (73.61% as of June 8, 2017) ServiceWorker 9 ● http://caniuse.com/#feat=serviceworkers
  10. 10. Sawood Alam <@ibnesayeed> reconstructive.js 10 ● https://github.com/oduwsdl/reconstructive ● A ServiceWorker script written for archival replay ● Plug-in for web archives or Memento aggregators ● Intercepts all network requests originated from a memento ● Reroutes requests to an archive (prevents live leakage & incorrect references) ● Optionally rewrites the content to add banner & to fix hyperlinks
  11. 11. Sawood Alam <@ibnesayeed> Zombies, No More! 11 ● https://github.com/oduwsdl/ipwb
  12. 12. Sawood Alam <@ibnesayeed> Rewriting Mementos is Expensive 12 Original capture (without any rewriting) In our experiment over 500 home pages we observed: ● One-fifth mean data overhead ● One-third mean time overhead 15% more data in twice the time
  13. 13. Sawood Alam <@ibnesayeed> Archival Capture Replay Test Suite (ACRTS) 13 reconstructive.js ● https://ibnesayeed.github.io/acrts/
  14. 14. Sawood Alam <@ibnesayeed> Reconstruction Winners: PyWB & reconstructive.js A. OpenWayback B. PyWB C. Memento Reconstruct D. Memento for Chrome E. reconstructive.js 14
  15. 15. Sawood Alam <@ibnesayeed> Future Work ● Use “Prefer” header for original content (when archives support it) ● Add a customizable archival banner ● Add click handler for lazy rewriting of hyperlinks ● Handle archived ServiceWorkers ● Write a 404-combat ServiceWorker script for webmasters 15 ● http://ws-dl.blogspot.co.uk/2016/08/2016-08-15-mementos-in-raw-take-two.html
  16. 16. Sawood Alam <@ibnesayeed> ● reconstructive.js => no zombies! ● Rerouting instead of rewriting (lazy rewriting) ● Mean overhead reduction ○ one-fifth data ○ one-third time ● 73.61% (and growing) browser support for ServiceWorker ○ http://caniuse.com/#feat=serviceworkers ● reconstructive.js ○ https://github.com/oduwsdl/reconstructive ● Archival Capture Replay Test Suite ○ https://ibnesayeed.github.io/acrts/ Conclusions 16

×