WebOrganics

Extending hCard using RDFa

2008-03-27T20:16:16+01:00

Mark Birbeck the Designer of RDFa has recently posted a couple of really good articles recently one about the first steps in adding Foaf to RDFa and a second one about using RDFa and Microformats. Both these articles has inspired me to write a little introduction about how to use the hcard microformat and extend it using RDFa.

I am going to mark up this example of a hCard as RDFa:


Martin McEvoy

Contact: Email
Web: WebOrganics

	N 53.7552,
	W -2.3675

I have included the geo part of hcard because its useful for people, clients, or customers to know where you are yes?

First add the RDFa document type to your page:

So far so good your page is now RDFa and you are ready to add some namespaces, a namespace is just a place where a set of names and definitions is stored.

I am going to use two namespaces in this example:

1. Foaf, xmlns:foaf="http://xmlns.com/foaf/0.1/"
Foaf Is primaraly used to define People, FOAF documents are machine-readable home pages.
2. Geo, xmlns:geo="http://www.w3.org/2003/01/geo/wgs84_pos#"
Geo Is the RDF equivalent of the World Geodetic System or WGS84 and is used to represent Latitude/Longitude information about the location of things.

There are two ways to add a namespace in RDFa one is In the tag of your page or another way is in the page using say a

or a I am going to add the namespace to the hcard markup itself:

@typeof is similar to a html

it describes a block of some thing, in this case Its a block of foaf:Person. @about means exactly as it says what this thing is about in this case Its about the foaf:Person weborganics.

Lets add a Name to this person:

Martin McEvoy

Easy eh?, Properties are use to add information about the subject, in this case a person, the contents are usually just text.

Next you may want to add your picture:

@rel is used in the same way as a html rel to describe the relationships between things. The above example has a relationship of a foaf:img of the foaf:Person. In RDFa you can use @rel anywhere in your page not just in links, you may also want to add your email address and homepage url in the same way:

Contact: Email Web: WebOrganics

You can leave it there if you wanted which is great! but I am going to take this a little further and demonstrate how you can mark up the Geo bit of a hcard. All in one go this time using the same techniques as demonstrated above:


    	
		N 53.7552, 
		W -2.3675

There Is one thing extra I have added I have used @content this works in the same way as the @title attribute in the abbr design pattern, Its used to carry machine readable data without it interfering with the human content, If you think about that from an accessible point of view its actually better than the current abbr design pattern.

So there you have it a hCard marked up as RDFa in a few easy steps. I have created two examples to accompany this mini how-to. which you can simply just copy and paste with your own details.

A Page marked up in just hcard
A Page marked up as a hCard+RDFa
The RDF output of hCard+RDFa (uses librdfa)

Microformats and RDFa work pretty well together I think, It adds Scope when previously there wasn't any, Microformats also make excellent building blocks for RDFa they give you hints on where everything should go. Thanks.

hAudio 0.9

2008-02-18T20:32:00+01:00

hAudio has reached a stately version 9.0 which I imagine will be the final proposal from the contributors of the hAudio Microformat.

Only one class name was changed, "fn" for "title" which doesn't seem so great but has been a hotly debated part of hAudio since May 2007 when the issue about "title is already taken to mean something else" and "use fn instead" first came up. The Class Name "title" may yet change again because the fn/title issue is still being debated and I imagine will continue for some time yet.

In the meantime the Grabb.it guys became the first major implementer of hAudio 0.9 marking up thousands of tracks on their userpages, I would say that they are quite happy with the changes made to the microformat.

hAudio RSS also uses the new hAudio microformat in the V3 version of the hypertext playlist format. New for Version 3, is a new home page on The ESW Wiki, hAudioRSS where you can download the entire source code and demo of the hAudio-RSS playlist.

If you are planning on marking up your pages in hAudio or hAudio-RSS let me know I will be more than happy to give you a shout for doing a good thing.

Talk about hAudio RSS

2008-01-24T19:13:00+01:00

hAudio-RSS is causing a little flutter in the open media web community so much so that back in December it became part of a small discussion over at songbird nest called Portable Playlists and other POSH-ibilities presented (amongst others) by Tantek which was kindly recorded to video by Citizen Tara Hunt, so without any further rambling may I present Tantek's Demo.

hAudio-RSS - Public Domain

2007-12-31T01:19:00+01:00

hAudio-RSS has been updated to version 2, the code has been modified and does not contain any suspected anti-patterns (info being scraped from the head not visible). The biggest change is that hAudio-RSS is now licensed under a Creative Commons Public Domain License. This is because microformats.org have recently required all contributions on the microformats wiki have a public domain license, which personally I find is a smart move, Anybody can freely use microformats anywhere for anything and not have to worry about possible licensing or copyright infringements. hAudio-RSS is an extension of hAudio so I feel it should have the same license. There is also a free Template that you can download of the whole hAudio-RSS v2 markup also released into the Public domain which includes, XHTML 1.0 Strict document, CSS, Bookmarklet, Buttons and guidelines. Download hRSS-template.

The hAudio transformation service has been improved! Instead of data being just dumped onto the screen the service now saves the transformation in a store, the url that you are given when transformation is complete is a permanent url to a static xml file, every time you re-run the hAudio xslt service you will be given a new permanent url in the store, this makes it easy to keep versions, or archives of your files, you can download the xml files anytime you like, save them to your desktop, or if you like re-syndicate your xml files to feedburner, add them to the podcast.net directory and pump them through another service like Grabb.it. do what you like its your data

Anyway lets not bore you anymore, download the template and have fun!

hAudio-RSS

2007-12-13T23:15:00+01:00

hAudio-RSS is a way of embeding an RSS2 Podcast in XHTML or more accurately a way of extracting a podcast from hAudio and XHTML using XSLT. Hypertext Podcasting if you like.

Its done by Embeding the hAudio Microformat in Semantic HTML and transforming it using XSLT.

The resulting transformation can then be played in Amarok or iTunes just like a podcast and (because the results are RSS2) you can read as an Audio blog feed in your favorite news Aggregator.

Example:

Source File: http://weborganics.co.uk/haudio-rss/

Because I am more a man of Science and not talk I have left some notes in the source file to give hints on how it is done.

After feedback and positive testing I will shortly be releasing all the source files and a transformation service that you can just download and drop in the back end of any site using PHP 5+ that will give publishers the ability to perform their own server side transformations (which will be great to add into templates just 6.3kb) and not have to use services like h2A and x2v much like all the other services in the WebOrganics Toolbox

For anyone who may be intrested there is a very beta Just an Idea kind of thing RDF site summary version of hAudio-RSS

hAudio Draft Specification

2007-11-04T00:34:00+01:00

It was announced on Saturday 3rd of November by hAudio editor Manu Sporny, that on hAudio 0.8 has become a Draft Specification

It was also announced that new Operator scripts would soon become available, combined with a new round of evangelism and rigorous testing for hAudio. The full hAudio Draft Specification can be read here http://microformats.org/wiki/haudio and a new test page based on hAudio 0.8 can be found here http://weborganics.co.uk/haudio

Audio Microformat hAudio 0.8

2007-11-02T00:41:00+01:00

This Halloween as well as that awful film Halloween being on the BBC again they also promised Halloween II next week... dont worry I have plenty more repeats to chose from thanks to the miracle of satelite tv, something else not so scary happened the audio microformat hAudio reached version 0.8. The general consensus on the list is that hAudio 0.8 will be the final proposal, after a last round of talks, before hAudio gets moved on to Draft. hAudio will then become only the twelfth in a list of many exploratory discussions, to make it to Microformat Draft.

Manu Sporny, Was the first to suggest a hAudio Microformat on Apr 6 2007, when he proposed that we...

Create a very simple hAudio microformat, which can then be integrated into media-info

...which was In response to my suggestion a few days earlier on Apr 4 2007 that the community could create a music download microformat using a combination of hAtom and hReview, a brave suggestion I thought, the Important thing was the discussion did not go stale.

Anyway check out the microformats wiki and find out what hAudio is, or have a look at the discussion, (7 months) and see what everyone got so worked up about. I have also updated the hAudio test page for any of you who are interested in publishing and testing hAudio.

hAudio RDFa

2007-08-24T10:56:00+01:00

hAudio has been creating quite a bit of exitement around the semantic web recently in particular the hAudio RDFa maping performed by David Lehn and Manu Sporny of Digital Bazaar, Inc.

The Creative Commons Tech Blog describes the proposal in its entry about Metadata work of interest as

...could turn out to be interesting for describing licensed content on the web, all rather interesting.

The Proposed hAudio RDFa maping can be found on the Digital Bazaar Wiki http://wiki.digitalbazaar.com/en/HAudio_RDFa a special well done to Manu Sporny because thanks to his efforts in the Microformats community and the RDFa community has become an invited expert in the W3C RDFa task force exellent news for both hAudio and Manu.
If you want to see a working example of hAudio RDFa as always WebOrganics has Produced an example with one or two tools to work with which can be found at http://weborganics.co.uk/files/hAudio-RDFa.xhtml The example also uses Valid XHTML-RDFa 1.0, something else to talk about at a later date?

hAudio and Operator

2007-08-07T03:38:00+01:00

There Is now an Operator User Script created by David Lehn called hAudio.js which will help you to detect all the hAudio items available on WebOrganics.
You can either visit Mike Kaply's (the creator of Operator) weblog and find out more about Operator and hAudio, or you can download hAudio.js directly from this site by clicking here.

hAudio Microformat

2007-06-27T22:22:00+01:00

Well! what can I say, I'm honored to announce the birth of a new microformat that has managed to reach the status of Proposal, hAudio.

I say honored because for some bizarre reason I managed to become a contributor whilst I was a the quest to make our very own Podcast more Organic and easier to share. I can honestly say that hAudio was one of the most hotly debated and well designed microformats since hAtom, and as a result the Format instead of taking the suggested eight weeks to complete, ended up finally taking twenty one contributors nearly twice as long.

The full proposal and full Schema can be found at http://microformats.org/wiki/audio-info-proposal

The demo page used for testing, and created during the hAudio discussion can be found at http://weborganics.co.uk/haudio

I would like to give a special "nod" to one or two of the guys who headed up the discussion and design of haudio, Manu Sporny who was the leader of the whole audio info discussion, without his guidance and Logic I doubt hAudio would ever been finished. Brian Suda and Tantek Çelik who kept us from straying too far beyond the "cow paths" Scott Reynen, David Janes, and Andy Mabbett all hot debaters and seasoned microformateers, who guided those of us who were not to sure where the cow path was. For my part well, my Ideas may have been a bit off the mark a little, Indeed most would say I found it hard keeping to the job at hand. In the end I think everyone that was involved helped create the most well designed microformat there is to date.