Comments on: PURL to be renewed http://ivan-herman.name/2007/07/15/purl-to-be-renewed/ Thu, 15 Jul 2010 13:00:30 +0000 hourly 1 http://wordpress.com/ By: Ivan Herman http://ivan-herman.name/2007/07/15/purl-to-be-renewed/#comment-1206 Ivan Herman Wed, 18 Jul 2007 08:03:27 +0000 http://ivanherman.wordpress.com/2007/07/15/purl-to-be-renewed/#comment-1206 True for Tabulator but, for example, the recipe's fail on that account :-( One has to reverse the order of rewrite rules to get the desired effect. I do not think we really disagree. Nobody said it cannot be done; what I said was that it is not very simple, and certainly not simple enough for potential Semantic Web users who, frankly, do not want to dive into the details of Accept headers... and a new PURL would be a great help. That is all. True for Tabulator but, for example, the recipe’s fail on that account :-( One has to reverse the order of rewrite rules to get the desired effect.
I do not think we really disagree. Nobody said it cannot be done; what I said was that it is not very simple, and certainly not simple enough for potential Semantic Web users who, frankly, do not want to dive into the details of Accept headers… and a new PURL would be a great help. That is all.

]]> By: Stelios Sfakianakis http://ivan-herman.name/2007/07/15/purl-to-be-renewed/#comment-1203 Stelios Sfakianakis Wed, 18 Jul 2007 07:04:40 +0000 http://ivanherman.wordpress.com/2007/07/15/purl-to-be-renewed/#comment-1203 Sure there are problems because content negotiation is not simple. Nevertheless, as in the case of the .htaccess recipe, it is assumed that a client interested in "semantic content" will give higher priority to application/rdf+xml than anything else (e.g. I think Tabulator sends something like this: Accept: application/rdf+xml, application/xhtml+xml;q=0.3, text/xml;q=0.2, application/xml;q=0.2, text/html;q=0.3, text/plain;q=0.1) while a common client (e.g. all current browsers) will not specify this media type at all in the Accept header. This of course may not be the case in the future (or even today..in some cases) so one can use e.g. http://jystewart.net/process/2005/06/managing-content-negotiation-with-php/ For my case I didn't pay too much attention to that... Cheers Stelios Sure there are problems because content negotiation is not simple. Nevertheless, as in the case of the .htaccess recipe, it is assumed that a client interested in “semantic content” will give higher priority to application/rdf+xml than anything else (e.g. I think Tabulator sends something like this: Accept: application/rdf+xml, application/xhtml+xml;q=0.3, text/xml;q=0.2, application/xml;q=0.2, text/html;q=0.3, text/plain;q=0.1) while a common client (e.g. all current browsers) will not specify this media type at all in the Accept header. This of course may not be the case in the future (or even today..in some cases) so one can use e.g. http://jystewart.net/process/2005/06/managing-content-negotiation-with-php/

For my case I didn’t pay too much attention to that…
Cheers
Stelios

]]> By: Ivan Herman http://ivan-herman.name/2007/07/15/purl-to-be-renewed/#comment-1185 Ivan Herman Mon, 16 Jul 2007 16:45:57 +0000 http://ivanherman.wordpress.com/2007/07/15/purl-to-be-renewed/#comment-1185 Well... it may not be that simple :-( I used the <a href="http://www.w3.org/TR/swbp-vocab-pub/#recipe3" rel="nofollow">Recipe #3</a> in the Best Practices document to set up (via .htaccess) my URI http://www.ivan-herman.net/Ivan_Herman but, as Richard Cyganiak found out, there are problems with that recipe if multiple formats are to be accepted. This is also the case with your example; indeed <code>Accept: text/html; application/rdf+xml;q=0.5</code> should return HTML but it will return RDF/XML… This is of course solvable with a slightly more complicated PHP script taking into account all possible combinations, but this does not invalidate my point: it may be too complex for a lambda user... Well… it may not be that simple :-(

I used the Recipe #3 in the Best Practices document to set up (via .htaccess) my URI http://www.ivan-herman.net/Ivan_Herman but, as Richard Cyganiak found out, there are problems with that recipe if multiple formats are to be accepted. This is also the case with your example; indeed

Accept: text/html; application/rdf+xml;q=0.5

should return HTML but it will return RDF/XML… This is of course solvable with a slightly more complicated PHP script taking into account all possible combinations, but this does not invalidate my point: it may be too complex for a lambda user…

]]> By: Stelios Sfakianakis http://ivan-herman.name/2007/07/15/purl-to-be-renewed/#comment-1180 Stelios Sfakianakis Sun, 15 Jul 2007 22:02:19 +0000 http://ivanherman.wordpress.com/2007/07/15/purl-to-be-renewed/#comment-1180 The PHP script: header("HTTP/1.1 303 See Other"); $ac = $_SERVER["HTTP_ACCEPT"]; if (strstr($ac, "application/rdf+xml")!= false) header("Location: http://ssfak.org/foaf.rdf"); else header("Location: http://ssfak.org/"); The PHP script:

header(“HTTP/1.1 303 See Other”);
$ac = $_SERVER["HTTP_ACCEPT"];
if (strstr($ac, “application/rdf+xml”)!= false)
header(“Location: http://ssfak.org/foaf.rdf“);
else
header(“Location: http://ssfak.org/“);

]]> By: Stelios Sfakianakis http://ivan-herman.name/2007/07/15/purl-to-be-renewed/#comment-1179 Stelios Sfakianakis Sun, 15 Jul 2007 22:00:54 +0000 http://ivanherman.wordpress.com/2007/07/15/purl-to-be-renewed/#comment-1179 <i>Unless one has access to the controls of his/her server (eg,to an .htaccess file for an Apache server), it is not that easy to adopt it in practice</i> Actually all it's needed is some decent support for producing dynamic content, e.g. with PHP. For my case http://ssfak.org/stelios/ responds with a 303 redirect taking into account the Accept header with the following PHP script stored in an index.php file in the ../stelios/ directory: Unless one has access to the controls of his/her server (eg,to an .htaccess file for an Apache server), it is not that easy to adopt it in practice

Actually all it’s needed is some decent support for producing dynamic content, e.g. with PHP. For my case http://ssfak.org/stelios/ responds with a 303 redirect taking into account the Accept header with the following PHP script stored in an index.php file in the ../stelios/ directory:

]]>