feed and rss protocols format

What are rss: and feed: links ?

Addresses like feed:http://example.org/rss.xml are typical feed protocol URI. They are used (at the moment of this writing) by feed readers/aggregators and other utilities related to feed processing. When you see them at a website, they look simmilar to the old XML icons, like in the following example:

These two protocols (feed and rss) allow syndication of feeds (like RSS or Atom) into your feed reader/aggregator software (like WinRSS, Vox Lite, FeedReader, ...).

Why not continue using HTTP ?

Two reasons (explained below):

http: cannot define actions.
http: cannot launch aggregator software from your browser software to perform subscription to a feed.

The main difference with http: URL is that feed: URI are to be processed by feed reader/aggregator software, while http: URL are usually processed by web browser software.

Like the mailto: protocol, which allows to define parameters (like Subject) feed: URI can express commands and parameters. Notice that http: cannot define commands, the only one is browse contents. When you enter an http URL in your browser, it always displays it.

Typical feed: commands are subscription to a particular feed (this is the default one), preview of the feed content, un-subscription from a particular feed, visit associated website or weblog, etcetera.

When you are browsing the web, and click a mailto: link, your e-mail software self-executes. Now, when you click a feed: link, your feed aggregator software self-executes.

Syntax

The new feed:// protocol is syntax compatible with the old rss:// protocol, it's only a matter of compatibility with previous software. rss:// is deprecated.

feed:[//]<extensions><feedurl>

Where

NAME	EXAMPLES	DESCRIPTION
feed:	feed: rss:	Protocol name
//	// nothing	Double slashes
<extensions>	see extensions nothing	Can be ignored
<feedurl>	http://example.org/rss.xml example.org/rss.xml	Feed address

<feedurl>

The <feedurl> part of the URL is the address of any valid feed, for instance, an http file. As with current web browsers, http: is the default protocol:

feed://example.org/rss.xml

Other protocols can be used, like network shared resources or local filesystem files. Use their corresponding syntax to form a valid feed: URI:

feed:file:///c|/my%20documents/news.xml (this is a Windows file)

feed://ftp://user:password@ftp.host.com/path/index.xml (FTP file transfer protocol)

feed://file://\\server\share\index.xml (a Windows networked file)

feed:file:///server/share/index.xml (another valid network format)

Simple link to a feed

By default, it is used to subscribe to that feed into your software:

feed://http://example.org/rss.xml

feed:http://example.org/rss.xml

feed:example.org/rss.xml

Using this format, your feed reader software should ask whether you want to subscribe to that feed or perform any other action (display information, visit website...). Please notice that your software does not need to be an aggregator, it could be a validator or any other future idea.

This link format is currently supported by Vox Lite and WinRSS. You should include the "http" part in the string, as "ftp", "file" and other protocols are also valid.

Feed aggregators with feed: support

The following feed readers already have support for the feed: protocol:

WinRSS feed reader

Vox Lite

FeedDemon

Tricks to make other feed readers feed: compatible:

Trick for SharpReader

Compatibility with the old rss: protocol (since April 2003) is only required if you want compatibility with WinRSS or Vox Lite old links.

Webmasters: changing icons from XML to FEED

In order to ease the transition to the feed: protocol, you should change your current XML, RSS or RDF links. Please follow these steps:

Change the "http:" part of the feed URL to "feed:"
Example:
http://example.org/rss.xml
becomes:
feed://example.org/rss.xml
Change the associated icon, to express the new feed format.
Get a copy (do not link directly) of feed.gif or create your own icon, for instance, an animated icon showing XML and FEED alternatively.
Do not use the new FEED icon with old links to http feeds, as that would confuse users (the RSS feed source code would be presented, and that's what the feed: protocol tries to avoid). Hint: Instead of replacing your old XML picture file, create a new one for the FEED.

Feedback

Collaborate in the description of the feed: protocol.

References

Permanent link for this page

More information about this new protocol can be found at:

Scheme predraft

Carnage4Life

Greg Reinacker's Weblog

Pete Hopkins' Pirate Typepad (1)

Pete Hopkins' Pirate Typepad (2)

Steven Wood

Richard S. Tallent, II

Christian Crumlish's A missing link in the appliance-ing of RSS

Jaykul : Hudled Masses

Copyright ©2002-2006 BRiNDYS Software. All rights reserved. BRiNDYS, WinRSS, GEDEX, SiCURE, SiCARIO, USUARi, Trasgo, BRiNotes and BRiRespa are marks or registered trademarks property of BRiNDYS Software.
Vox Lite is Copyright 2003 Steven Wood.