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.

ResourceSync Quick Overview

1,806 views

Published on

This presentation introduces ResourceSync, a specification aimed to enable web-based synchronization of resources. The specification is the result of a collaboration between NISO and the Open Archives Initiative funded by the Sloan Foundation and JISC. The proposed resource synchronization approach is based on several existing specifications (e.g. Sitemaps, PubSubHubbub, well-known URI) and is aligned with common architectural principles (e.g. REST, follow your nose).

A 15 minute video version of these slides is available at https://www.youtube.com/watch?v=ASQ4jMYytsA

Published in: Technology
  • Be the first to comment

ResourceSync Quick Overview

  1. 1. http://www.openarchives.org/rs #ResourceSync ResourceSync A Quick Overview Herbert Van de Sompel Los Alamos National Laboratory @hvdsomp - herbertv@lanl.gov ResourceSync was funded by the Sloan Foundation & JISC The ResourceSync editors are: Martin Klein (LANL), Robert Sanderson (LANL), Herbert Van de Sompel (LANL), Simeon Warner (Cornell U.), Graham Klyne (Oxford U.), Bernhard Haslhofer (U. of Vienna), Michael L. Nelson (Old Dominion U.), Carl Lagoze (U. of Michigan) Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  2. 2. ResourceSync • Collaboration between NISO and the Open Archives Initiative, 2012- 2013 • Funded by the Sloan Foundation and JISC • Goal: Devise a specification for web-based resource synchronization • Subjects of synchronization: web resources identified by HTTP URIs • HTTP as the communication protocol for synchronization • Servers involved in synchronization are on the web Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  3. 3. Problem Statement • Consideration: • Source (server) has resources that change over time: they get created, modified, deleted • Destinations (servers) leverage (some) resources of the Source • Problem: • Destinations want to keep in step with the resource changes at the Source Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  4. 4. A Source’s Resources
  5. 5. A Source’s Resources Evolve over Time
  6. 6. A Source’s Resources Evolve over Time
  7. 7. A Source’s Resources Evolve over Time
  8. 8. A Source’s Resources Evolve over Time
  9. 9. A Source’s Resources Evolve over Time
  10. 10. A Source’s Resources Evolve over Time
  11. 11. Problem Statement • Consideration: • Source (server) A has resources that change over time: they get created, modified, deleted • Destination (servers) X, Y, and Z leverage (some) resources of Source A • Problem: • Destinations want to keep in step with the resource changes at Source A • Goal: • Design an approach for resource synchronization aligned with the Web Architecture that has a fair chance of adoption by different communities Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  12. 12. One to Many – Master Copy
  13. 13. Many to One - Aggregator
  14. 14. Metadata Harvesting
  15. 15. Solution Perspective • Source communicates about the state of its resources: • Publish inventory: snapshot of the state of resources at a moment in time • Publish changes: enumeration of resource changes that occurred during a temporal interval • Notify about changes: send notifications as changes occur Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  16. 16. Solution Perspective – Communication Payload • Payload of the communications: • Always: HTTP URI of the resource • For change communications: change type (create | update | delete) & datetime of change • As needed: metadata and links pertaining to the resource Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  17. 17. ResourceSync is Based on Sitemaps • Sitemap is the document format used throughout the framework o Used widely by web servers to advertise their resources to search engines <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9”> <url> <loc>http://example.com/res1</loc> <lastmod>2013-01-02T13:00:00Z</lastmod> </url> <url> <loc>http://example.com/res2</loc> <lastmod>2013-01-02T14:00:00Z</lastmod> </url> … </urlset> Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  18. 18. ResourceSync Extends Sitemaps • Extensions to Sitemaps to support synchronization o <rs:ln> for links o <rs:md> for metadata <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9”> xmlns:rs="http://www.openarchives.org/rs/terms/”> <rs:ln …/> <rs:md …/> <url> <loc>http://example.com/res1</loc> <lastmod>2013-01-02T13:00:00Z</lastmod> <rs:ln …/> <rs:md …/> </url> … </urlset> Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  19. 19. Publish Resource List: Inventory at Tx • In order to meet a Destination’s need for baseline synchronization, the Source may publish a Resource List • A Resource List is an inventory, a snapshot of existing resources • Per resource, it minimally provides the resource’s URI • Process: - Destination obtains the Resource List - Destination obtains listed resources by their URI Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  20. 20. Publish Resource List: Inventory at Tx Resource List @Tx = { A ; B ; C }
  21. 21. <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:rs="http://www.openarchives.org/rs/terms/"> <rs:md capability="resourcelist" at="2013-01-03T09:00:00Z” /> <url> <loc>http://example.com/res1</loc> <lastmod>2013-01-02T13:00:00Z</lastmod> <rs:md hash="md5:1584abdf8ebdc9802ac0c6a7402c03b6" length="8876” type="text/html"/> <rs:ln href="http://example.com/meta/dc/res1" rel=”describedby” type=”application/xml"/> Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014 </url> … </urlset> Resource List
  22. 22. Send Change Notification: Resource Changes as they Occur • In order to meet a Destination’s need for incremental synchronization and low latency, the Source may send Change Notifications • A Change Notification conveys resource change events as they occur • For each event, it minimally lists the URI of the resource, the nature of the change, the datetime of the event - Process: - Destination receives Change Notification - Destination obtains created/updated resources, removes deleted resources Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  23. 23. Send Change Notification: Resource Changes at Ta Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014 Change Notification @Ta = { A updated @Ta }
  24. 24. Send Change Notification: Resource Changes at Tb Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014 Change Notification @Tb = { D updated @Tb }
  25. 25. Send Change Notification: Resource Changes at Tc Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014 Change Notification @Tc = { A updated @Tc ; B updated @Tc }
  26. 26. ResourceSync Notifications are Based on the PuSH Protocol • ResourceSync builds on the PubHubsHubbub protocol (PuSH) used for syndication of Atom/RSS feeds • Destination subscribes to a Source’s notifications via an intermediate Hub Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  27. 27. Modular Framework • ResourceSync specifies additional synchronization capabilities • Source decides which capabilities to support based on local and community requirements Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  28. 28. Follow Your Nose Discovery • ResourceSync specifies mechanisms for Destinations to determine whether and how a Source supports the framework • Based on conventions for web discovery and documents that detail the level of support Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  29. 29. Follow Your Nose Document Navigation • ResourceSync specifies mechanisms to navigate the various documents involved in the framework • Based on following typed links Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  30. 30. Status • Core specification (pull) is ANSI/NISO Z39.99-2014 • Notification (push), Archives specifications in beta • Growing implementation interest motivated by the need to move beyond metadata (OAI-PMH) • Tools will be listed at http://www.openarchives.org/rs/t oc Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014
  31. 31. Specifications: http://www.openarchives.org/rs ResourceSync A Quick Overview Herbert Van de Sompel Los Alamos National Laboratory @hvdsomp - herbertv@lanl.gov Google Group: https://groups.google.com/d/forum/resourcesync The ResourceSync editors are: Martin Klein (LANL), Robert Sanderson (LANL), Herbert Van de Sompel (LANL), Simeon Warner (Cornell U.), Graham Klyne (Oxford U.), Bernhard Haslhofer (U. of Vienna), Michael L. Nelson (Old Dominion U.), Carl Lagoze (U. of Michigan) Herbert Van de Sompel - ResourceSync NISO Annual Update, ALA, Las Vegas, NV, 29 June 2014

×