Hi Tom, sorry for the slow reply, I've been busy.
On 16/03/07, Tom Heath <tom.heath(a)gmail.com> wrote:
...It can be
summarised as "if your server responds with a 200 range code to a
URI, it's an information resource; but anything within that resource
with a fragment identifier is not".
If I've understood the theory correctly, then yes, this is largely
true and fine if you simply have an RDF document at the URI (in a
document that defines an ontology, for example), but is incorrect if
the information resource is an HTML document (where a fragment
identifier identifies a part of the document, i.e. an information
resource). Therefore we probably shouldn't make that assumption, but
instead say "we don't know what a hash URI identifies".
Okay, I guess that's a fair call.
Richard Cyganiak covers this quite nicely I think:
<snip>If TimBL says that hash URIs always represent concepts, and not
part of documents, then he contradicts RFC 3986 and introduces an
ambiguity that is just as bad as the original "URI crisis" which
httpRange-14 was designed to solve.</snip>
Hrm. Interesting discussion, thanks for the pointer. I certainly don't
agree with that John Black fellow about "claims". RFC 3986 confuses me
somewhat, as it says "Fragment identifiers... [allow] an author to
specifically identify aspects of an existing resource..." This seems
to imply that a fragment only refers to an aspect of a resource, which
sounds at odds with fragmentInXML-28
), which says:
"In general, the fragment part of a URI may be used to refer to
abstractions as well as syntactic fragments of a representation".
Still, it's not really our place to try and resolve this issue here; a
perfectly acceptable workaround exists in the form of the 303 redirect
proposed by the resolution to httpRange-14. So that's fine, I'm happy.
I prefer slash URIs as I believe they make a clearer
distinction between a thing and a document about a thing (and 303
redirects help avoid any ambiguity). They also send a stronger message
about a URI of a thing being independent of any one particular
Yeah, sure; to a human a pile of line-noise (.?&=%bleah) isn't too
clear. Would you prefer example.com/guide/Foo_Bar/rdf
Also, since those would be the 303
redirects, what would they redirect to?
For example, even though it makes no difference at the
machine level, as a human being using
to identify the pub in a different document would still niggle me a
bit. It just seems the wrong way around; surely the pub is the primary
object, and any particular description of it is secondary?
Right. I'm sure we can hash something better out.
"obj" itself was something I made up after failing to
find a better alternative to the word "thing", which I have a strong
dislike for. I'm happy for better suggestions.
I think it's fine, it follows the Ronseal approach. Would be
interested in hearing you reasons for dislike of "thing", although
you're welcome to save that for a face to face discussion over a beer
sometime if you'd prefer.
Aw, no, I just think it sounds kind of weak. I think maybe "a strong
aversion" was a little strong, it's more of a niggling dislike. :)
don't follow... The RDF is completely independent of
anything; it was hand-composed. Unless you're referring to schemata
(yay Greek!) that we rely on as modules, rather than Perl modules?
OK, that's interesting, I hadn't realised that. What I was really
getting at is that (as I understand it) the OG software relies on Perl
modules for generic Wiki functionality (of course I may be totally
wide of the mark here, having never really delved around under the
hood). If that is the case then our ability to redfine the addressing
scheme for OpenGuides and create "pretty URIs" may be limited, as the
modules define the URI syntax. Please clarify things for me if I'm
wrong about this.
Right. Well, at present the CGI interface defines the URI syntax, but
we control the code, so the format of the URIs is entirely up to us.
What can be thought of can be coded.
Just so I follow you, are you wedded to the fragment
themselves, or simply the distinction between the "object/thing" and
the "document about the object/thing"?
Definitely the latter.
But you could
alternatively, the wn:Neighborhood item "Rotherhithe" could be given
Your version is more compact, but doesn't specify that Rotherhithe is
a wn:Neighborhood, which is an explicit definition that I quite like.
The more semantics the better I reckon, so saying that it's a
Neighbo(u)rhood would be great. Something like:
<uriForRotherhithe> foaf:isPrimaryTopicOf <documentAboutRotherhithe>
<uriForRotherhithe> rdf:type wn:Neighborhood
might be a nice way to express these things (would need to double
check this before commiting it to code); I'm not totally sure of the
semantics of rdfs:isDefinedBy, so not sure if we can make such a
strong claim as <uriForRotherhithe> rdfs:isDefinedBy
<documentAboutRotherhithe> (hence foaf:isPrimaryTopicOf).
I'll look into it.
Not necessarily. If
returned a HTTP303 response and a "Location:
(where <http://wherever.openguides.org/contributors/bob/about> was a
document describing Bob) then we'd be doing the right thing aswell.
The # isn't essential.
Yep. That's great.