- From: Miles, AJ \(Alistair\) <A.J.Miles@rl.ac.uk>
- Date: Mon, 3 Oct 2005 16:20:16 +0100
- To: <semantic-web@w3.org>, <public-esw-thes@w3.org>, <public-swbp-wg@w3.org>
Hi all, A short while ago I posted a proposed URI dereferencing policy & setup for SKOS Core [1] as a possible candidate for future best practice wrt 'hash' RDF namespaces. To sum up what it does: basically, if the client asks for html, it gets redirect to the latest version of the html documentation, and if the client asks for rdf, it gets redirected to the latest version of the rdf description. This was to satisfy two requirements: (Requirement 1) property & class URIs are 'clickable' in web browsers and take you to human readable stuff. (Requirement 2) provenance of any rdf statements about classes/props is always a date-stamped version of the 'ontology', allowing determination of which 'version' is being used by an application at run-time. I've tried to implement this setup as a test on the W3C server, but have run into a problem and so am posting this in the hope that those who know apache better than me can tell me what's going on (i.e. help! :) I've got the following setup: In the directory /2004/02/skos/ there is a file 'bar.var' which looks like ... --- URI: bar URI: core-latest-rdf Content-type: application/rdf+xml URI: core-latest-html Content-type: text/html URI: core-latest-html Content-type: text/xml URI: core-latest-html Content-type: application/xml URI: core-latest-html Content-type: application/xhtml+xml --- I added the following lines to .htaccess in /2004/02/skos/ ... --- RewriteRule ^core-latest-rdf$ /2004/02/skos/core/history/2005-03-31 [R=303] RewriteRule ^core-latest-html$ /TR/2005/WD-swbp-skos-core-spec-20050510 [R=303] --- (So the idea was to test if I could make the URI http://www.w3.org/2004/02/skos/bar behave how we ultimately want the URI http://www.w3.org/2004/02/skos/core to behave). Now, if I try to GET http://www.w3.org/2004/02/skos/bar.var everything behaves as I would like, with a redirect to different resources dependent on the 'Accept:' header in the original request. However, if I try to GET http://www.w3.org/2004/02/skos/bar I get a 404 not found. It's obviously getting to the type-map file, because of the header returned by the server (see below, the 'Content-Location:' field), but for some reason is not doing the subsequent redirect. Here's the HTTP trace, anyone know what's going on? ... --- http://www.w3.org/2004/02/skos/bar GET /2004/02/skos/bar HTTP/1.1 Host: www.w3.org User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.11) Gecko/20050728 Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 300 Proxy-Connection: keep-alive HTTP/1.x 404 Not Found Date: Mon, 03 Oct 2005 15:10:16 GMT Server: Apache/1.3.33 (Unix) PHP/4.3.10 Content-Location: core-latest-html Vary: negotiate,accept TCN: choice P3P: policyref="http://www.w3.org/2001/05/P3P/p3p.xml" Last-Modified: Mon, 05 Sep 2005 07:47:53 GMT Etag: "431bf829;43414560" Accept-Ranges: bytes Content-Length: 2006 Content-Type: text/html; charset=iso-8859-1 X-Cache: MISS from wwwcache.rl.ac.uk Proxy-Connection: close ---------------------------------------------------------- http://www.w3.org/2004/02/skos/bar GET /2004/02/skos/bar HTTP/1.1 Host: www.w3.org User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.11) Gecko/20050728 Accept: application/rdf+xml Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 300 Proxy-Connection: keep-alive HTTP/1.x 404 Not Found Date: Mon, 03 Oct 2005 15:15:13 GMT Server: Apache/1.3.33 (Unix) PHP/4.3.10 Content-Location: core-latest-rdf Vary: negotiate,accept TCN: choice P3P: policyref="http://www.w3.org/2001/05/P3P/p3p.xml" Last-Modified: Mon, 05 Sep 2005 07:47:53 GMT Etag: "431bf829;43414560" Accept-Ranges: bytes Content-Length: 2006 Content-Type: text/html; charset=iso-8859-1 X-Cache: MISS from wwwcache.rl.ac.uk Proxy-Connection: close ---------------------------------------------------------- http://www.w3.org/2004/02/skos/bar.var GET /2004/02/skos/bar.var HTTP/1.1 Host: www.w3.org User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.11) Gecko/20050728 Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 300 Proxy-Connection: keep-alive HTTP/1.x 303 See Other Date: Mon, 03 Oct 2005 15:15:50 GMT Server: Apache/1.3.33 (Unix) PHP/4.3.10 Content-Location: core-latest-html Vary: negotiate,accept TCN: choice Location: http://www.w3.org/TR/2005/WD-swbp-skos-core-spec-20050510 Content-Type: text/html; charset=iso-8859-1 X-Cache: MISS from wwwcache.rl.ac.uk Proxy-Connection: close ---------------------------------------------------------- http://www.w3.org/2004/02/skos/bar.var GET /2004/02/skos/bar.var HTTP/1.1 Host: www.w3.org User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.11) Gecko/20050728 Accept: application/rdf+xml Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 300 Proxy-Connection: keep-alive HTTP/1.x 303 See Other Date: Mon, 03 Oct 2005 15:15:43 GMT Server: Apache/1.3.33 (Unix) PHP/4.3.10 Content-Location: core-latest-rdf Vary: negotiate,accept TCN: choice Location: http://www.w3.org/2004/02/skos/core/history/2005-03-31 Content-Type: text/html; charset=iso-8859-1 X-Cache: MISS from wwwcache.rl.ac.uk Proxy-Connection: close --- Cheers, Al. [1] http://lists.w3.org/Archives/Public/public-esw-thes/2005Sep/0008.html --- Alistair Miles Research Associate CCLRC - Rutherford Appleton Laboratory Building R1 Room 1.60 Fermi Avenue Chilton Didcot Oxfordshire OX11 0QX United Kingdom Email: a.j.miles@rl.ac.uk Tel: +44 (0)1235 445440
Received on Monday, 3 October 2005 15:20:30 UTC