RDF and mod_rewrite

I was reading the Best Practice Recipes for Publishing RDF Vocabularies and looking for an easy way to provide HTML and RDF on my site. At the moment I have (very) limited RDF but I wanted something that would allow me to have cool(ish) URIs automatically. Basically, a system that would work out if I have an HTML or RDF file depending on your request.

So, http://duncan.dickinson.name/card should give you:

• card.html if you're a web browser


• card.rdf if you want semantic data

This stretched my mod_rewrite skills but the following seems to work:

# Turn off MultiViews
Options -MultiViews -Indexes 
DirectoryIndex card.html index.html index.htm index.php

# Directive to ensure *.rdf files served as appropriate content type,
# if not present in main apache config
AddType application/rdf+xml .rdf

# Rewrite engine setup
RewriteEngine On
RewriteBase /

#Check if an RDF page exists, and return it
RewriteCond %{HTTP_ACCEPT} application/rdf\+xml
RewriteCond %{REQUEST_FILENAME}.rdf -f
RewriteCond %{REQUEST_URI} !^/.*/$
RewriteRule (.*) $1.rdf [L,R=303]

#Provide a default RDF page 
RewriteCond %{HTTP_ACCEPT} application/rdf\+xml
RewriteCond %{REQUEST_URI} ^/$
RewriteRule .* /card.rdf [L,R=303]

#Provide the HTML for the request
RewriteCond %{REQUEST_FILENAME}.html -f
RewriteCond %{REQUEST_URI} !^/.*/$
RewriteRule (.*) $1.html [L,R=303]

#provide the PHP page for the request
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteCond %{REQUEST_URI} !^/.*/$
RewriteRule (.*) $1.php [L,R=303]

Using some help I got curl looking at my site's rdf:

curl -H "Accept: application/rdf+xml" http://duncan.dickinson.name/card

So now I get back a 303 redirect.