viernes, enero 12, 2007

Taller básico de RSS

Workshop Outline

What is RSS?  Viewing Feeds  Create One  Validate it  Display it  Register it  Example Sites  Example Code  Resources  
Popdex Citations
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RSS Workshop Bryan Bell's RSS Badge

Publish and Syndicate Your News to the Web

"If you build it and have great content, they will come"

Tutorial URL: http://rssgov.com/rssworkshop.html

Workshop Description

In this workshop you'll learn how to create, validate, parse, publish, and syndicate your own RSS news channel. The emphasis will be the practical application of the two most popular varieties of RSS for dynamic publishing.

You can use RSS channels to allow customers to keep up on industry specific news, check weather, look for jobs, view upcoming concerts or university lectures, monitor specific websites, and much more. Some examples of the varieties of applications that government agencies and others have created:

Government Examples

More examples: see RSS in Government blog

 

 

 

 

 

Business Examples

 


This workshop will also teach you how others can incorporate your news into their pages automatically. The workshop will showcase the use of tools that are readily available to you.

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What is RSS?

RSS is a protocol, an application of XML, that provides an open method of syndicating and aggregating Web content. Using RSS files, you can create a data feed that supplies headlines, links, and article summaries from your Web site. Users can have constantly updated content from web sites delivered to them via a news aggregator, a piece of software specifically tailored to receive these types of feeds. RSS is the hottest thing in Web communication. It powers many popular applications such as weblogs, knowledge management networks, and news syndication.

Weblogging, a term coined by Jorn Barger in December 1997, is one of the most popular and fast growing applications of RSS. A blog is someone's personal dated 'log' frequently updated with new information about a particular subject or range of subjects.

RSS is changing the world of publishing news and searching for news. Here's how, Chad Dickerson, the Chief Technology Officer at at InfoWorld describes the change:

" I've spent a lot of time in conference rooms patiently explaining RSS to business folks here at InfoWorld and to developers at some other IDG publications, always emphasizing how simple it is: you can do it and here's how. ...It was only recently (April 28, 2003, to be exact) that I felt like RSS had completely turned the corner at InfoWorld when the various constituenices at InfoWorld (sales, editorial, and technology) agreed to include links to our feeds prominently on our home page. Getting something on the home page is recognition that something has been politically mainstreamed within an organization. So, what's my point? RSS is now burned into InfoWorld's organizational brain like the words Kleenex and Xerox. Names can change, specs can change, people involved can change, and any number of other things can change, but in the end, if any of the business folks ask me.... I'll just say: don't worry about the name, it's really just RSS...." Source.

RSS 0.91 (Rich Site Summary)

Netscape released version 0.91 xml rss feed in July, 1999 and has since been upgraded by Dave Winer of Userland to 0.92 xml rss feed, and in August 2002 to 0.94 and 2.0 xml rss feed. The latest version is the first to support extensionability with optional namespaces in its first module, blogChannel. For more detail see Ben Hammersley's Content Syndication with RSS, chapter 4 (pdf) and chapter 8 and Sam Ruby's RSS in Depth with Quick Summary.


RSS 1.0 (RDF Site Summary)

RDF or Resource Description Framework, provides an XML structure for describing document metadata content. The RSS-DEV Working Group created RSS version. 1.0 (official specification) in December 2000 supporting RDF thus allowing the description and syndication of site content and metadata. It differs from the earlier version because of its extensibility via modules based on XML-Namespace technology. This lets content providers use it in their own documents plugging functionality into a basic syndication platform, saving time and effort, and ensuring compatibility. RSS 1.0 documents can draw upon any RDF-compatible extension syntaxes called modules. Current standardized modules exist for Dublin Core, Syndication, Content, and Annotation. For more detail see Ben Hammersley's Content Syndication with RSS, chapter 6 and Sam Ruby's RSS in Depth with Quick Summary.

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What Does a RSS File Look Like?

It's a good idea to learn how an RSS file is structured before you begin creating them. RSS files are written in XML [this orange XML logo is used to represent a link or pointer to the syndicated form of a news feed].

Let's take a look at and compare the two flavors of RSS:

XMLHack ..................... 0.91 xml rss feed | 1.0 xml rss feed
Dive into Mark .............. 2.0 xml rss feed

tima thinking outloud ..... 2.0 index xml rss feed |
2.0 full xml rss feed | 1.0 xml rss feed

Some things both formats have in common:

  • the XML declaration: <?xml version="1.0"?>, often including the encoding scheme
  • channel elements:
    • title - the name of the channel
    • description - a short description of the channel
    • link - an HTML link to the channel Web site
    • language/dc:language - the language encoding of the channel (for example en-us)
    • image - an optional link to a site logo
  • one or more item elements with titles, links, and descriptions

Notice the differences. The1.0 version feed is wrapped in the RDF namespace declartion, <rdf:RDF> ... </rdf:RDF>,, has a table of contents in the channel block (used by aggregators), and employs Dublin Core metadata fields.

Want to know the full details about the various elements used in 0.92 feeds? See Matthew Trump's RSS 0.92: A Step-by-Step Beginner's Guide. and Mark Pilgrim's article What is RSS?

RSS 1.0 conforms to the W3C RDF specification. RDF is a model for describing metadata for describing resources from a collection of web sites, a single web site, parts of web pages, a specific HTML or XML element, documents, printed books, recipes, etc. A property is an attribute or characteristic used to describe a resource and is specified in the RDF Schema specification. The resource together with a named property plus the value of that property is an RDF statement. All statements are enclosed in an RDF element which has a namespace prefix pointing to the RDF syntax specification:

<?xml version="1.0"? encoding="UTF-8"?>
<rdf:RDF xmlns:rsdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"</rdf:RDF>

The RDF schema, calls for each channel to have a title, description, link to the channel on your Web site, and then item elements. You can include optional information about the channel: language, PICS rating, copyright statement, pubDate or publication date of the channel, lastBuildDate showing the date it was last updated, docs, link to the managingEditor, link to the webMaster, an image such as a logo, textinput strings, skipHours telling automated aggregators when not to collect RSS data, and skipDays telling aggregators days that data should not be collected.

News stories in your RSS feed are items defined by the <item> tag and usually containing a headline <title>, the URL to the RSS feed or <link>, and an optional <description>. RDF feeds were traditionally limited to 15 items, but that limitation is largely a matter of convention. Syndic8's Headlines Per Day shows that some feeds can number in the hundreds, but keep them reasonable so they readily load into feed readers.

Don't put HTML markup code within a headline. If necessary in a description, such as for a link, the HTML characters &, ", <, and > will need to be encoded as &amp;, &quot;, &alt;, and &gt; . The RSS 2.0 specification specifically allows it. Ben Hammersley argues against putting HTML coding in description for two reasons. It requires that client software have the ability to parse it, and combining presentation markup along with the content diminishes the ability of RSS in being able to provide indexable metadata.


Find a Viewer to View RSS Channels

To get acquainted with RSS, we'll first view a RSS channel through a RSS reader or viewer. In this workshop, we'll view ResearchBuzz (0.91) xml rss feed and Perl News (1.0) xml rss feed using an online viewer and a client-side news aggregator. Try this exercise:

    1. Go to UKOLN's RSS-Xpress RSS channel viewer and editor.
    2. Click view to see the HTML presentation. Click "edit and then "save" or "source" to view XML.
      Optional: For comparsion, view Perl News using Redland RSS 1.0 Viewer. Check "yes" to format the results in a simple box.

    Now we'll find these same two feeds in Syndic8, the largest RSS syndicator. Notice the tabs at the bottom of the page. Click "headlines" to read the current feed. Click the "integration" tab to access files prepared for several other alternative readers including NewsIsFree, Headline Viewer, Fyuze, Radio Userland, Snewp, Amphetadesk, and BottomFeeder.

    Let's take a look at one of these client-side readers that you may wish to install on your computer:

    Andrey Tumashinov's NewsZCrawler – ($25). This Windows reader has many features and is easy to set up. It synthesizes RSS news feeds, NNTP newsgroups, and news web sites. It can write as well as read news.

    See our Searching RSS Channels for News Workshop for information about other spiffy news aggregators that you can download and configure.


Create your own channel and news headlines

You can create a RSS file using any text editor, but you almost certainly will find syntax errors. You may find it preferable to create channels using one of these editors and then maintain them using a text editor. This isn't a bad practice, if the channel is for something ephemeral. If the channel items are not archived and if the channel isn't integrally associated with a particular site, editing the channel with a text editor is easy and fast. Otherwise, you'll probably prefer to use a content managment system (CMS) tool to maintain channel data.

In this workshop, we are going to construct a simple RSS channel. We're going to start with "Documents in the News" a news page constructed in standard HTML by Government Documents Librarian, Peter Kraus, at the University of Utah Marriott Library. The "before" page is the page as it existed on September 24, 2002, and "current" is the page as it currently exists.

When you're done with today's workshop, you will have created a RSS channel (either in 0.9 or 1.0 xml rss feed ) and you will have published the same page with the information now dynamically appearing as an RSS channel (style sheet optional).

We'll create a channel for "Documents in the News" by using the first two tools listed here:

  • UKOLN's RSS-Xpress by Andy Powell and Pete Cliff is a superb web-based RSS channel editor and directory. RSS-xpress editor forms RSS 1.0 XML, but is currently restricted to 15 items per channel. Click "add event details" for additional fields. Edit, save files locally, then load them to your server. Nice for distributed RSS content management.
    "Documents in the News" RSS example - xml rss feed


  • WebReference's RSS Channel Editor - like UKOLN's, this editor is limited to 15 items, but this online form will generate valid RSS 0.91 feeds. Build a new channel or "fetch" an existing one, click "build RSS," and then save the resulting file. A similar web-based generator that can be used to construct RSS 0.91 feeds is Andy Holt's RSS Headline Generator.

If you're interested in more than an individual channel, then you're better off using a blogger or content management product that use RSS. Most support automatic archiving to store old posts, permalinks (to link to them), date headers and time stamps that record when new headlines were posted. Some provide hosting for you site for free or for a low cost. Some require a client-side download; some are managed entirely through a web interface. [Suggestion: include a "generator" comment line such as <!-- generator="Movable Type/2.51" --> on the line following the XML declaration. This allows Syndic8 and others to track the usage of these tools.]

Here is an incomplete list that links to several of the more popular alternatives.

  • Blogger Products is a server-side product line, including subscription services, for creating RSS 0.91 feeds. Blogger Pro has spellcheck, image uploading and team blogging. Blogger is a creation of Evan Williams and Meg Hourihan of Pyra and is generally credited for first popularizing blogging. Pyra was recently purchased by Google.

  • Radio Userland - Dave Winer's easy-to-use blog host with client-side CMS product for Windows and Mac with facilities for creating, reading, and archiving RSS feeds for a single blog. It can be made collaborative by use of the Multi-Author Weblog Tool. It is designed to be used from one main location, though updates can be remotely if you have remote access to your workstation. Manilla is a server-side product that supports building a community of blogs and Frontier is the overall CMS.

  • Movable Type by Benjamin and Mena G. Trott -- popular and feature-rich, extensible, server-based Perl CMS, free for personal or non-profit use; $150 for government agencies Commercial Pro version due out in summer. Easy to use for maintaining regularly-updated news or journal sites, like weblogs. Supports XML-RPC and creates custom 0.92 and 2.0 (.xml) and 1.0 (.rdf) RSS channels. Supports the creation of "collaborative weblogs", i.e. multiple authors and visitors can contribute postings and/or make comments. Has language packs that translate the display into other languages such as Spanish. Imports Radio Userland created channels and archives, but comments are lost. Must have server access. Example of a subscription list. Utilizes "trackback pings" enabling you to see all sites that have referenced a post on your site and to read related posts (trackback example) enabling distributed communications. See admin interface screenshots.

  • Typepad - Ben and Mena Trott's centrally hosted commercial weblogging service. It's like using Movable Type only easier and with some unique features.

  • NewZCrawler - this client-side news reader also creates outgoing channels in RSS 0.92 to which you can add your news using its news composer (template-based news feed output allows you to create any output text format). If you have a webblog, the program also has a Blog Client allowing you to post news via the blogger XML-RPC API.

  • News Is Free - Once registered, you can register multiple channels and manage them simultaneously using their online "Post to Your Blog" editor.

  • Onclave - a free web-based system in beta testing by Drew Peloso, Dave Reid, Steve Hatch, and Per Kreipke for creating and managing multiple online collaborative weblogs, managing the information with directory-like taxonomies. Users can put information into appropriate categories, or create new topics as needed. You can create RSS 0.91 channels by creating a personal or collaborative (cblog) onclave, adding a weblog channel, and syndicating as RSS. There is no software to download. Publishing is done dragging the Share-it! editor to your browser toolbar. When you see an article you want to share with others, click Share-it, enter the item title and description, and click publish. Click the syndicate button to create the RSS XML file or the simple javascript code to parse and display the channel to your site. Visitors can subscribe by email to your syndicated channel by clicking the notify button and you can post entries by email. gilsUtah example. - receive channel by email.

  • WebCrimson - content management tool by John Hiler's company for free, easy-to-use online browser creation of a "weblog" , adding a weblog to an existing site, creating a WebZine on your site or hosted on theirs, or contribute "articles" using browser editor. Includes full FTP, templates, WYSIWYG editor, permissions and admin contro for group contributions, and optional hosting on their servers.

  • pMachine Free - free PHP product and hosting service that supports collective weblogs and installs, like Movable Type, on your own server. The commercial pMarchine Pro supports multi-layered interactive news sites.

  • Blosxom - a free lightweight, yet feature-laden weblog creator by Rael Dornfest; in Perl (runs on any OS, but built to take advantage of the Mac OS X). Possibly the most useful "61 lines of code" on the Internet. A simple PERL plug-in by DJ Adams allows you to post entries by email. Pyblosxom is a python version (Abe Fettig's example).

  • Noah Grey's Greymatter [mirror] - free opensource Perl, server-based weblogging and journal software.

  • Tidakada.com's B2 - a PHP4 open source blogging tool that creates RSS 1.0 and 2.0 feeds. Pages are generated dynamically from a MySQL database.

  • LiveJournal - a large weblogging hosted community whose servers can host your online journal. Their downloadable client software supports Mac, Windows, BeOS and UNIX.

  • Byline - an open source Python weblogging system that can operate in either a client-based or server-based mode, but lacks a web-based interface

  • Textpattern - a PHP/mySQL content managed blogging system currently in beta.

  • Syncato - Kimbro Staken's weblogging system that stores posts in an XML database (Requires Python and Sleepycat Berkeley DB XML)

  • PyDS (Python Desktop Server) - George Bauer's combined Weblog authoring tool, XMLRPC/SOAP server, and news aggregator (Requires Python).

  • Blogware - Tucows' new weblog platform software available only through a licensed Blogware Reseller.

  • Serence Corporations's KlipFarm - register as a Klip Provider to make channels. The service also has an alert service, an XML-based Windows desktop application that grabs streaming RSS feeds, and Klip Folio, a free Windows client-side viewer that you can download.

  • Tom Dyson's Mailbucket - some aggregators allow you to post entries to a blog via email. Mailbucket is an experimental email-to-RSS service that allows you to create a public RSS 1.0 feed and post to it by email. Perhaps useful for creating mailing list feeds.

  • Some popular open source, server-side, portal content management systems such as PostNuke, (php), PHP-Nuke,(php) phpWebLog (php), SlashDot (Perl), Squishdot (Zope), Rusty Foster's Scoop (Perl), Roller (Java), and Drupal (php) can also create and display RSS feeds using their built-in news aggregators. They are very popular for community sites. Scott Johnson has a tutorial for creating feeds using Drupal. Both Drupal and Scoop can support multiple blogs and Drupal have a module for customized news aggregation. Here are two of my favorite community implementations:

A handy tool for comparing features between over 25 of the more popular RSS creators is:

If you find all these choice bewildering, take a look at John Hiler's great pros-and-cons comparisons and taxonomy: The Microcontent News Blogging Software Roundup.

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Machine Created RSS Channels

Content created in HTML by yourself or others can be converted to RSS feeds by means of "scraping". Scrapers try to identify "headlines" in a page and they create feeds that are OK but not of the quality of human produced feeds. You can use one of the free online scraping services or download their source code to your own server and run a scraping service of your own.

You can assist these scraping programs by putting special span tags around content that you want syndicated. The text inside the tags is pulled out and put into an RSS file.

Put <span class="rss:item"> ... </span> tags around any items on a page that you want to syndicate by RSS (such as a list of links or events).

Then submit the URL to:

    Ian Davis' myRSS is a python program that converts web data into XHTML RSS channels. Enter a web page URL in the Create a Channel form.. Channels are created in RSS 0.91, RSS 1.0, and in javascript include formats, and are updated daily. myRSS delivers, using a heuristic algorithm, the last 15 headlines or hyperlinked resources that have been added to the page. This could be a very useful tool for syndicating a site what's new page, agency news, new acquisition lists, donations received, and the like. A myRSS style sheet can be associated to a feed if you wish to display a myRSS channel on a page. The services uses item link redirects on the myRSS server that in turn link to the referred to resources. Anyone can "sponsor" a channel for a $10 annual fee and have the redirect links removed. Anyone can pay $25 per year to have a channel updated hourly instead of daily. Noteworthy channels created in this manner are reviewed, and if acceptable, are annotated and are included in the DMOZ Open Directory project and in Syndic8.com's database. You can download the entire myRSS Channel Catalog in OCS, an xml format for describing channel catalogs. MyRSS turned this workshop into these two RSS 1.0 xml rss feed xml rss feed channels; new items posted to the State of Utah homepage are in this xml rss feed channel.

    Syndic8 Syndicate Your Page- an online form to generate the feed and list it with the Syndic8 aggregator. What to syndicate content created by someone else? Use the Syndica8 "suggest" service to create channels using myRSS.

    RSSify at Voidstar.com - an online form by Julian Bond to generate a RSS 0.92 feed

If you want to do the creation yourself, download and install either:

    Blogfeed. - a Perl script from Adam Kalsey's Consulting Group

    RSSify - a PHP script by Julian Bond that creates RSS 0.92 channels with up to 25 items.

    Eric Vitiello's Slurp - a downloadable Perl script that retreives HTML pages and converts them into RSS 1.0.

Some tools specific to Radio Userland are:

  • eVictor's rssDistiller - a commercial tool for RadioUserland that extracts RSS feeds from most HTML pages and allowing you to join the results of several filters into a single feed. For example, Bruce Loebrich has used this tool to creat RSS channels from Google News xml rss feed and Columbia University Newsblaster xml rss feed syndications.

  • Mark Paschal's Stapler - a Radio Userland RSS extractor tool


Validate Your RSS

As a channel editor, it is your responsibility to ensure that your file can be parsed by the XML parser of any subscribing site. Your RSS creation software should validate XML at the time of creation, but some do not. Minor errors can make the feed unreadable. You may wish to load your RSS file to your server and then enter the URL in one of the following validators to check the syntax.

  • Feed Validator (formerly RSS Validator) by Mark Pilgrim and Sam Ruby. Version 1.2.3 now validates multiple syndication formats: RSS 1.0, RSS 0.9x/2.0, and the new Pie/Echo/Atom 0.2 feeds. It includes validation for common namespaces. If you have access to a server with a Python distribution, you can download the open source code and follow the instructions to install it locally.


  • Dave Becket's Redland RSS 1.0 Viewer. RSS to HTML converter, but acts as a RSS 1.0 validator also. Viewer offers several parsing methods. Links to a great collection of feeds about RSS.

  • Experimental Online RSS 1.0 Validator. The Schematron is by Rick Jelliffe and the report by David Carlisle modified by Leigh Dodds validates for namespace, core structure, core content, field lengths, RSS 0.91 module structure and content, and Dublin Core module structure. Leigh's beta test validator further checks core modules and some proposed modules.

  • Userland RSS Validator - for RSS 0.91, RSS 0.92

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Parse and Display Your RSS Channel on Your Site

Since RSS files are written in XML, you cannot readily display them in a page without parsing them for the information you want to show. Content management and blogging systems like Radio Userland, Movable Type, and Drupal automatically parse and publish this to your site without any extra effort on your part.

If you are using a text editor to create channels, or if you want to display your RSS content on another site such as one created with DreamWeaver or Frontpage, you'll need to insert an "include" that calls upon an external parsing program.

These parsing programs coupled with stylesheets allow you to display this content the way that you want it to appear. You can choose the fonts and colors, the number of channel items to display, whether or not to show the headline summaries or descriptions, and whether or not to show the time/date stamps. Parsers will allow you to display multiple channels, if you so desire, all on the same page.

There are many solutions to choose from. In many cases all you need to do is to put a single-line javascript into a page, connecting the location of the RSS channel to the location of the parser. If the feed already exists as a javascript (.js file), you just need to call it. For example, to display the LockerGnome daily tip just insert:

<script language="JavaScript" src="http://www.lockergnome.com/syndicate/tip.js"></script>

Which displays as:



Other examples:

<script type="text/javascript" language="javascript" src="http://www.epnworld-reporter.com/news/headline_feed.php"></script>

<script language="javascript" type="text/javascript" src="http://agency.utah.gov/cgi-bin/parsername.cgi?rss=http://agency.utah.gov/rsschannelname.xml"></script>

<script type="text/javascript" language="Javascript" src="http://mkdoc.com/news/headline.js"></script>\

You may want to include a NOSCRIPT option for users who either have javascript disabled or who are using screen readers. Kansas City infoZine uses a javascript include that looks like this:

<script language="JavaScript" src="http://rss.infozine.com/feed/rss2js.php?src=http://rss.infozine.com/kc/headlines.xml">
</script>
<!-- alternative for no javascript -->
<noscript>
<a href="http://rss.infozine.com/feed/rss2html.php?src=http://rss.infozine.com/kc/headlines.xml">View infoZine Headlines</a>
</noscript>

 

Some scripts will allow you to use style sheets to customize the look and feel of the channel to match that of your site.

Here's how the process works:

Start with empty page shell

add the channel by inserting the javascript

attach the link to the - style sheet , and

voila!

You have two choices. You can either install one of these parsing programs on your own server, or you can point the "include" to a script residing on someone else's server. Let's test the waters first by pointing to a parser on another server. Here are a few options:

Adam Curry's RSS-Box Viewer [mirror] - a service in beta that parses all versions of RSS. Use the online form to select table size, fonts, colors, maximum item numbers, and whether to display compact or expanded. It then creates the javascript with embedded variables. Supported stylesheet classes are: .rssBoxTitle, .rssBoxContent, rssBoxItemTitle and rssBoxItemContent. Write to Adam for the full code if you want to host it locally (written in Rebol, an Internet messaging language). The script to insert, for our "Documents in the News" example, looks like this:

<script language="javascript" src="http://publish.curry.com/rss/rss-box.r?url=http://gils.utah.gov/secure/rss/kraus91.rss&align=
left&width=350&frameColor=white&titleBarColor=%23ffffff&titleBarTextColor=cc0000&boxFillColor=white&textColor=
black&fontFace=Times New Roman&maxItems=7&compact=&xmlButton=&javascript=true"></script>


"Documents in the News" demo - XML - stylesheet



RSSxpress-Lite by Andy Powell and Pete Cliff of UKOLN. Click "try it" and Select a channel - -
Enter the URL of the channel that you just created and loaded to your server. It produces a line of javascript that you just cut and paste. You can use style sheets to customize the colors, fonts, and display. Support documentation. For example:

<script src="http://rssxpress.ukoln.ac.uk/lite/viewers/rss.cgi?rss=http://slashdot.org/slashdot.rdf"></script>

Demo - Demo - stylesheet



RSSViewer is the Utah State Library's modification (by permission) of Pete Cliff's simplified RSSxpress-Lite. This Perl script uses customizable stylesheets. Contact Ray Matthews to be added to the user list or to use the script on your own agency's server.

<script src="http://66.186.201.46/cgi-bin/rssviewer.cgi?rss=http://gils.utah.gov/secure/rss/lib_master.xml"></script>

Demo (with descriptions) - stylesheet

RSSIndexViewer is the same script but only for displaying a channel "index". Use it if you want to display item headlines but not item descriptions.

<script language="JavaScript" type="text/javascript" src="http://66.186.201.46/cgi-bin/rssindexviewer.cgi?rss=http://gils.utah.gov/secure/rss/lib_seasonal.xml">

Demo (index only) - stylesheet



Wytheville CC News Center - an ASP parser for all RSS versions by David Carter-Todd.. Enter the location for your feed and it generates a javascript pointing to the instance on their server. For example:

<SCRIPT LANGUAGE=JavaScript SRC=http://www.wcc.vccs.edu/services/news/channel.asp?c=http%3A%2F%2Fwww%2Esearchguild%2Ecom%2Fnews%5Foutput%2Ephp%3Ff%3D2></SCRIPT>

And showing how to limit the number of headlines displayed:

<SCRIPT LANGUAGE=JavaScript
SRC=http://www.wc.cc.va.us/services/news/channel.asp?c=http://www.pandia.com/searchworld/pandia.rss&bg=cccccc&limit=6></SCRIPT>

You can also download the code.
Demo - Capitol Connections Training


After you have tried this, you'll probably want to load a script to your own server so that you have more customization options and assurances of reliability. Most are open source and free to download and use, and they come in a wide variety of programming languages.

Our RSS Parsing Programs page describes many of these options with links to working examples, documentation, and the urls where you can download them.

Allow other Sites to Publish Your RSS Channel

You'll want to let others read your channel and publish it to their site. Syndication is the process of sharing content among sites. This other other websites and applications to include your updated headlines. Websites should create an information page, about syndicating their headlines. One standard that was created by UserLand and is being used increasingly is to include this XML image somewhere on your site and link it to the RSS XML for that page. To publish other feeds on your site, first check licensing agreements; an example is that of MagPortal.com.

Another thing you can do is to allow people to subscribe to your site by email. Onclave supports this as well as:

Bloglet - a super slick XML-RPC, RSS-to-email conversion subscription service by Monsur Hossain for the blogs you create. Allows others to receive email subscriptions of your blog and you can receive daily stats on your subscribers. Also can be used to stay up-to-date on your favorite sites by subscribing to any existing RSS feed. Add a subscription box to your site, for your own or anyone elses channel. It creates the code to add. Use the FeedMe toolbar icon to automatically subscribe to feeds that incorporate auto-discovery. For example:

Enter your email address below to subscribe to Utah and National Public Library News!xml rss feed


powered by Bloglet


Register Your Channel with a RSS Aggregator

Before going public, proofread to make sure that your channel has a correct URL link, descriptive title, and an informative and accurate description. DMOZ weblog editor, Laura, has compiled some useful tips.

Next, submit your channel to aggregators just as you would submit your website to search engines. You'll be amazed at the traffic it will generate.

An aggregator is a web site or system that collects RSS feeds from multiple sources and then does something with them. Usually this will involve collating and displaying the contents of each feed and perhaps creating new composite feeds from them. Here are a few of the larger aggregators:

  • Syndic8 - the largest aggregator with almost 10,000 feeds-- recommend your own or another's; created by Jeff Barr

  • Userland

  • OnContent - add your feed to their database and use their server to syndicate your content; registering allows you to display feeds from there on your own site

  • Calaba's XMLTree - a directory

  • NewsIsFree - by Mike Krus has headlines from a fast-growing collection of more than 3,600 feeds.

  • News4Sites - a commercial aggregator that monitors 8,000 web pages from 2,500 domains producing more than 25,000 news headlines organized into over 2,200l channels of up to 20 headlines per channel. Feeds are generated in ten formats: javascript, RSS, PHP, ASP, C#, VB.NET, WDDX, XML RPC, CDF, and PERL. They can be parsed or delivered by email. The feeds are available for free with advertisements. Suggest a site for inclusion.

  • Submit a Weblog to the EatonWeb Portal - search for over 8,000 RSS channels or browse by category

  • Daypop - if your channel offers news or current events, add to this excellant Google-like search of over 7,500 news feeds. Use Daypop Backlinks to see who is linking to you.

  • Shanti Braford's PopDex: the website popularity index - crawls sites and analyzes links to rank the most popular stories from Internet news sites, blogs, and weblogging resources. Use Popdex Citations to see who is linking to you and Searchbox to search other blogs from your site. Email Shanti.

  • Backwash - a PHP driven community site of independent columnists who recommend the best specific Internet content. Bills itself "the ultimate recommendation engine." Register and then submit.

  • Morton Frederickson's Syndication Subscription Service consolidates the multiplicity of aggregation services. A green subscribe icon subscribe - subscribe on a page will take you to a page (example) that lets you choose the subscription link for the aggregator of your choice. Clicking the icon there will add the linked RSS feed to your subscription list.


Some of these sites provide categorized lists of their channels in OCS (Open Content Syndication) and OPML (Open Processor Markup Language) formats. OCS is an xml format for describing channel catalogs.

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Use Auto-Discovery Aggregation

You can facilitate aggregators finding your channel by inserting a LINK specification within the HTML <head> that tells the location of your RSS feed. If your tool hasn't already implemented this, you can add this a simple one-line statement using the HTML link tag:

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

Some real world examples by Rael Dornfest and Mike Krus:

<link rel="alternate" type="application/rss+xml" title="RSS" href="http://www.oreillynet.com/meerkat/?_fl=rss10" />
<link rel="alternate" type="application/rss+xml" title="XML" href="http://www.newsisfree.com/news/index.rdf">

Each RSS feed that you have should have its own defined LINK tag with its own unique title.

Mark Pilgrim's Auto-subscribe Bookmarklets. Drag the link to your link toolbar and whenever you visit a site that you want to add to your news aggregator of choice, click your "Subscribe" button on your link toolbar, and it will try to find the site's RSS feed and auto-subscribe you. Nifty!

Likewise, Onclave comes with a Share-It bookmarklet and the latest version of Movable Type comes with a "MT It!" allowing you to use the bookmarklet from your right-click menu.

More and more news aggregators and programs are supporting auto-discovery including:

  • NewsIsFree - If you create an account with this headline aggregator by Mike Krus, you can use the web site as a cloud-based personal aggregator. Any of the feeds it collects can be added to custom pages that you define. Their OCS Service List is an XML of exportable RSS channels.

  • Jeff Barr's Syndic8

  • LiveJournal, a collaborative open source free service for most platforms allowing you to create an online journal from syndicated feeds. Once you've created a journal, add /RSS to the end of the URL to view it in RSS format.

  • Rael Dornfest's Meerkat

  • Drupal has a powerful built-in site-cloud News Aggregator for reading and blogging news from other sites.

  • Joe Gregorio's Aggie 1.0 RC3 opensource, native .NET newsreader. Enter a URL of a web page into the Add Channel box and if the web page supports auto-discovery Aggie will find its RSS file.

  • Keith Devens' PHP RSS Aggregator

  • BlogLinker.com is a unique free tool from Zaeem Maqsood.for reciprocal linking and increasing traffic to your site. Register, insert a javascrfipt and add links. If the website you link to is also registered, then your site will automatically appear in their list of links.

  • Mark Pilgrim, of dive into mark, has created autorss.py, a Python script to find a site's RSS feed and to search for a referring site's RSS feed in auto-linkbacks. It can be used programmatically (the autorss.getRSSLink function) or on the command line:

    [f8dy]$ python autorss.py http://diveintomark.org/
    http://diveintomark.org/xml/rss.xml

  • Technorati - enter the URL of your page and it will show you the pages currently linked to you ranked by "blog authority" and "freshness." For a fee, create a "watchlist" based on your own URL or search terms and and have Google send you a daily email or RSS feed..

  • Julian Bond's GNews2RSS - a free online form (and PHP script that you can put on your own serve) that will that will perform a Google News search query and turn the results into an RSS feed.

  • Phil Pearson's Blogging Ecosystem - analyzes links between members of weblog communities. It scans nearly 14,000 blogs and lists the 501 most popular blogs (by back links) and the blogs that each listed blog in turn links to (forward links). Use it to check blog popularity and to see who is linked to whom. For example, at this writing, Phil Windley's Enterprise Computing is the 220th most popular because 74 others link to it. Calculates nearest neighbors, levels of linkedness, degrees of separation between any two blogs.

See the DMOZ RSS Autodiscovery category for more links.

The CGI Resource Index has links to a considerable number of PERL programs, such as Moreover's News Fetcher, that allow you display headlines from other RSS feeds on your site.

Sites Employing RSS

RSS Resources

 

Workshops for Utah State Agencies

Do you work in the Salt Lake City area? If so, register for one of our RSS workshops held at the Utah State Library:

 

More Tutorials

Books: Online or available from the Utah State Library

  • Hammersley, B. (2003). Content Syndication with RSS. The most thorough and recent explanation in print of RSS syndication, news readers, and news aggregators, such as Meerkat, Syndic8, and Newsisfree. O'Reilly has chapter 4 online. NewsGator has chapter 2 online.
  • Powers, S.; Doctorow, C.; Johnson, J.S.; Trott, M.G.; Trott, B. (2002) Essential Blogging. A guide to installing and using Blogger, Blogger Pro,Radio Userland, Movable Type, and Blosxom.
  • Pilgrim, M. Dive Into Accessibility: 30 days to a more accessible web site
    An excellent online book that includes tips and tricks for making Radio Userland, Blogger Pro, Greymatter, Manilla, and Movable Type sites accessible.
  • Chromatic, Aker, B, and Krieger, D. (2002). Running Weblogs with Slash. Though Slash is no longer the platform of choice for a RSS driven community portal, this is a detailed illustration how RSS can be used to manage web content.

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Ray Matthews

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