When Persistent isn't!

barbie on 2007-04-23T17:07:30

"A PURL is a Persistent Uniform Resource Locator ..."

So says purl.org. Except the Namespace URL used within XML::Atom (http://purl.org/atom/ns), doesn't exist. I'm assuming someone actually created a PURL in the first place, if they didn't then no biscuits for Ben or Miyagawa ;)


Wrong version...

LTjake on 2007-04-23T19:52:51

IIRC, http://purl.org/atom/ns is the namespace for the 0.3 (i.e draft) spec. The 1.0 namespace is http://www.w3.org/2005/Atom. The following will generate a feed with the 1.0 namespace:

XML::Atom::Feed->new( Version => 1.0 )

Re:Wrong version...

barbie on 2007-04-23T22:53:12

I was testing with Atom 0.3 :)

As it happens one of the recommended ways to switch to Version 1.0 ($XML::Atom::DefaultVersion = "1.0";) doesn't work either :(

URIs != webpages

Aristotle on 2007-04-23T21:43:08

XML namespaces use URIs as identifiers – Uniform Resource Identifiers. URIs need not actually be resolvable to anything. Even if a URI starts with the “http:” scheme, that means nothing more than that HTTP ownership rules apply; it does not mean there has to be a page there if you actually try to dereference the URI. (HTTP ownership rules are that whoever owns the DNS for the host part of the HTTP URI can mint new HTTP URIs with that host part.)

There used to be a distinction such that URIs which can be resolved were called URLs (Uniform Resource Locators) and those which could not were called URNs (Uniform Resource Names). However, this distinction turned out to be nonsensical – there is no qualitative difference – and has long since been dropped, and along with it, the terms “URL” and “URN”. Only the “URI” term exists in official Internet jargon now.

Re:URIs != webpages

barbie on 2007-04-23T23:04:26

I think you missed the main point of the post. The PURL, as in Persistent URL, didn't exist.

I know the difference between a URL and a URI. The fact that a URI didn't resolve didn't prompt the post. The fact that it used a supposedly persistent address did ;)