Copyright iredale Consulting 2002
Rich Site Summary/Resource Description Framework technology is a simple method of a site describing what it has, so that another site can summarise the content, and provide links back to the original content.
RSS was pioneered by Netscape Communications for their my.netscape portal, and adopted quickly by many others, notably userland.com.
A simple XML file is produced by the site originating the articles. This file, easily obtainable by HTTP, is downloaded and parsed by the client, allowing the client to present the site summary in a way that suits the client. XML provides a simple human readable format that is easy to generate and read, using typical web tools.
The module came from a simple idea, gather RSS feeds, convert them into HTML fragments and then template them into a web page on a local web server.
Originally I used wget, to pull files down from their server. Other tools to do this include cURL and any web browser. I cached the RSS feeds on my web server's disk space to reduce unnecessary downloading.
RSS feeds come in several incompatible formats. To make conversion to HTML simple I opted to convert all RSS feeds to RSS version 0.91 as this is very simple to convert to HTML via XSL-Templating. The underlying XML::RSS core can parse and convert RSS Versions 0.9, 0.91 and 1.0, it does not as yet deal with 0.92 or 2.0.
Most online examples of RSS use the XML::RSS module to programmatically convert the feed into HTML, either directly or via using one of the many quality HTML templating tools. This I felt was inefficient and so I opted to use "XML Style Sheet Language Transformation", which is industry standard and does not require programming. There are several XSL-T engines available: Saxon, Xalan, MSXML, and Sablotron, however the fastest and easiest one for Perl is Matt Sergeant's GNOME based LibXSLT.
After developing the script to do this I realised that much of the code could be converted into a module and distributed to the world. After a popular post to Perlmonks, I have moved the module up to CPAN. The code should be considered as beta code, and the API may change somewhat in the near future.
Some basic examples of how to use this module are provided in the examples folder. Simple explanations can be found here:
Copyright iredale Consulting 2002