Copyright 2005 Digital Enterprise Research Institute. All rights reserved.

www.deri.org

DM110 Emerging Web Media

Dr. John Breslin

john.breslin@deri.orghttp://sw.deri.org/~jbreslin/

Week 9: Content Syndication

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Recap of syndication and news readers

• Content is “syndicated” from many blog and news sites in computer-readable “feeds” that can be used by other systems

• For example, content from RTÉ or my blog is syndicated so that headlines / articles can be reused by other people in their own websites or applications

• Syndication format is usually RSS• Some sites use a different syndication format:

– Blogger.com uses “Atom”

• Can use news readers to read multiple feeds:– bloglines.com, Thunderbird, PlanetPlanet, etc.

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The syndication of content

• Syndication is used for publishing new content regularly

• Content is provided from many blogs and news sites in a common format that can be reused by other websites and applications in a “syndication” process

• Rather than mass-spamming via e-mail, interested parties can subscribe to feeds to be notified about changes or updates to information (self service!)

• A common syndication format can have many uses, including connecting services together, “mashing” together of data, etc.– We’ll see mashing with Yahoo! Pipes later…

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Not just for blog subscriptions

• The latest items, with hyperlinks, titles and summaries, are syndicated using computer-readable formats (e.g. for reading favourite blogs with a feed reader)

• Since “items” can be virtually anything, RSS can be and is used for more than just blog headline syndication:– Newspaper articles (one of the original usages), library updates,

recipes, shared calendars (RSSCalendar.com), podcasts, videos, job posts, weather reports, financial updates, bug reports, wiki page changes, new photo uploads, forum thread replies, etc.

• Strength (and weakness!) is in its generality

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RSS for libraries

• Useful for both librarians and members of libraries since libraries publish lot of announcements, e.g. general notices, activity bulletins, online resources, and TOCs for journals

• NUI Galway’s library uses RSS 1.0 to publish lists of their new books and resources:– http://www.nuigalway.ie/web/

add-ons/rss_reader.html

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What is RSS?

• The most common syndication format(s)• Acronyms:

– “Really Simple Syndication”– “Rich Site Summary”– “RDF Site Summary”

• Eight “flavours”:– Not including Atom!

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RSS development timeline

• The RSS fork:– diveintomark.org/archives/2002/09/06/history_of_the_rss_fork

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RSS technologies

• RDF:– RSS 0.90, 1.0, 1.1– RSS 1.0 is a Semantic Web RDF vocabulary for syndication– Using RDF allows the inclusion of other vocabularies to

supplement the terms in the RSS 1.0 vocabulary, e.g. dc:author (Dublin Core), foaf:Person (Friend of a Friend)

• XML:– RSS 0.91, 0.92, 0.93, 0.94, 2.0

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What is Atom?

• Another syndication system• Based on XML (not RDF), but efforts towards AtomOWL• Emphasis has shifted from the format to the API

• Specification:– Constructs: content, people, dates and links– Elements: feeds, with entries– http://www.atomenabled.org/developers/syndication/atom-

format-spec.php– http://www.intertwingly.net/wiki/pie/Motivation– http://www.atomowl.org/

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The good news is that…

• …you don't have to worry about which feed format your blog provides, because practically any aggregator or news reader worth its salt will be able to read it anyway!

• …if you want to help the Semantic Web effort, can use the RSS 1.0 variant (RDF) as it allows you to combine with other vocabularies such as FOAF, Dublin Core, etc.

1.0

0.9 0.91 0.92 2.0 Atom

Simple: Plain XML

Extensible: RDF

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Explosion of RSS feeds

– http://www.syndic8.com/stats.php?section=overview

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RSS 1.0 terms

• Class “channel”:– Property “title”– Property “link”– Property “description”– Property “items” (rdf:Seq)– …

• Class “item”:– Property “title”– Property “link”– Property “description”– …

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RSS 1.0 example

<?xml version="1.0"?>

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns="http://purl.org/rss/1.0/"><channel rdf:about="http://sw.deri.ie/~jbreslin/ttdig/ttdig_tourist.rss"><title>TTDIG Tourist</title><link>http://sw.deri.ie:2020/~jbreslin/ttdig/index.php?jcategory=tourist</

link><description>Things to Do in Galway, Tourist</description><items> <rdf:Seq> <rdf:li resource="#1" /> <rdf:li resource="#2" /> … </rdf:Seq></items></channel>…

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RSS 1.0 example (2)

<item rdf:about="#1"><title>Galway: St. Nicholas' Cathedral</title><description>Located on Market Street, Galway. St. Nicholas' Collegiate

Church dates from the 12th century. Christopher Columbus visited this church in 1477, fifteen years before he set out for the New World. Sometimes hosts concerts, a nice venue where Lambchop and gospel singers alike have played.</description>

</item><item rdf:about="#2"><title>Galway: Lorna McMahon's Gardens</title><description>Located in Bushy Park, Galway. Only allows visitors once a

year! Magnificent gardens which surround Lorna Mc Mahon's home and were created by her single handed. For 25 years, she has carved out a delightful and in places magical garden from hazel wood, rough scrub, rocks and bog. The garden extends over 4 acres, and is subdivided into 12 gardens each with its own specialty. The garden is a personal project and several sections are called after friends and relatives. There is a Japanese garden with a large brooding 'snow viewing' lantern and by way of contrast there is a herbal garden laid out in Elizabethan style containing all the herbs mentioned in the Bible or in Shakespearean plays.</description>

</item>…</rdf:RDF>

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Aggregators and readers

• Syndicated content allows one to check multiple feeds on a regular basis using aggregators or feed readers:– Previously, semi-regular visits to bookmarked sites– Feeds of syndicated content can now be pulled into readers– Also, intelligent pushing of feeds (e.g. with “pingback”)

• Can highlight new or updated posts

• Allows you to quickly scan for relevant content through a larger volume of content items

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Some examples of readers

• http://en.wikipedia.org/wiki/News_aggregator

– http://en.wikipedia.org/wiki/Mozilla_Thunderbird (Desktop)– http://www.feedreader.com/ (Desktop)

– http://www.bloglines.com/ (Web)– http://reader.google.com/ (Web)

– http://www.planetplanet.org/ (Server)– http://www.gregarius.net/ (Server)

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Bloglines (web reader)

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Thunderbird (desktop reader)

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PlanetPlanet (server aggregator)

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RSS aggregators for Irish blogs

• IrishBlogs.ie– First Irish blogs aggregator,

well known

– Now has an Irish blogs directory

• planet.journals.ie– ~1500 “Irish” blogs at present

– Launched 1st April 2005

– Open inclusion policy

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RSS auto-detection

• Applications (aggregators or browsers) can automatically detect RSS on pages from links in the HTML header like:

<head>

…

<link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.johnbreslin.com/blog/feed/">

</head>

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Mashing RSS using Pipes from Yahoo!

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Gathering (many of) my contributions

• “Subscribe to my brain”:– http://api.flickr.com/services/feeds/photos_public.gne?

id=62377636@N00&format=rss_200– http://del.icio.us/rss/Cloudie– http://upcoming.org/syndicate/v2/my_events/16248– http://www.slideshare.net/rss/user/Cloud– http://www.allconsuming.net/person/Cloud/rss– http://ws.audioscrobbler.com/1.0/user/Cloudie/recenttracks.rss– http://www.youtube.com/rss/user/jgbreslin/videos.rss– http://www.johnbreslin.com/blog/feed/– http://www.johnbreslin.com/wiki/index.php?

title=Special:Recentchanges&feed=rss

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Bringing them all together to “subscribe to my brain”