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RSS or content syndication in 10 minutes
by Erik Dasque, Project Manager, Novell
Date Created: 2001-08-21 13:20:00.000
  Introduction
  The RSS Specification(s)
  RSS Resources
  Conclusion
introduction
The Internet and Intranet waves are all about accessing information. Each morning, I go through a folder in my browser's bookmark list called "Every Day." This is where I find the list of Web sites that I visit on a daily basis to understand what is going on in the world and with technology, photography, Java-all of my interests, both professional and personal.

Portals are about centralizing the specific information that an individual wants and needs to see during the day to do his job better. In other words, portals give us a personalized view of the information that is most important to us.

A few years ago, I noticed that most public portals (i.e. My Netscape, My Yahoo, etc.) were starting to offer content from many different sources, including smaller Web sites with very specific topics. Netscape did this by allowing content providers to "plug-in" to the My Netscape portal and publish a file in the RSS format, which is essentially an XML application. This is how RSS came into existence.

the RSS specification(s)
From its RDF (documents that specify lightweight ontology, or the nature and relationship of beings) roots, RSS (formerly "RDF Site Description") was renamed "Rich Site Summary" with version 0.91. For this version, new elements from scriptingNews were added to create a more complex format for syndication-focused Web writing.

The main addition to RSS version 0.91 was an item-level <description> element, which strengthened the format's presence in the content syndication arena. With RSS versions 0.92 and 0.93 coming, and RSS version 1.0 still in the proposal stage, an exact RSS standard is still unclear, but consider the following RSS basics:

RSS describes a channel, such as the following:

  • Title
  • Link
  • Description
  • Image
  • TextInput
  • ...
RSS channels consist of URL-retrievable items (n) such as the following:
  • Title
  • Link
  • Description
  • ...
the RSS resources
RSS files are written in a simple and easy to read XML structure.
 
  
<?xml version="1.0" ?>



         <!DOCTYPE rss



           PUBLIC "-//Netscape Communications//DTD RSS 0.91//EN" "http://my.netscape.com/publish/formats/rss-0.91.dtd">



         <rss version="0.91">
 
<channel>
(The channel core metadata)
 
<title>Wired News</title>



<link>http://www.wirednews.com/</link>



<description>Technology, and the way we do business, is changing the world we know.



Wired News is a tec...ou in the picture.</description>



<language>en-us</language>



<pubDate>Sat, 07 April 2001 04:02 PDT</pubDate>



<image>



          <title>Wired News</title>



          <url>http://static.wired.com/news/images/netcenterb.gif</url>



          <link>http://www.wirednews.com/</link>



</image>
(The items metadata)
 
<item>



          <title>The Meaning of Life and Microbes</title>



          <link>http://www.wirednews.com/news/technology/0,1282,42838,00.html</link>



          <description>NASA's new Astrobiology Institute ... Hembree.</description>



</item>







<item>



          <title>Anoter item</title>



          <link>http://www.wirednews.com/news/technology/0,1234,42838,00.html</link>



          <description>Another item description</description>



</item>
 
</channel>
 
 
 
</rss>
 
 
 
 
 
 
As you can see, RSS files are self-explanatory, and should you want to generate one, they are easy to create with any mechanism normally used to create dynamic HTML pages. (e.g. Java servlets, JSPs, Perl, PHP, Python, ASP, etc.)

Because they are so simple to read, RSS files are easy to display. In fact, a typical consumption model would be as follows: An application downloads the RSS file periodically (or on client request), parses it (it is XML after all), and uses an XSLT engine to transform it into HTML.

While SilverStream ePortal's next major release will allow you to easily consume and generate RSS files, you can now find useful information and many examples of RSS at the following addresses:

conclusion
RSS has revolutionized content syndication because it allows for a simple and easy way to grab and centralize personalized content for Web site users. Look for a SilverStream ePortal RSS component very soon!