Re: RDF validator error

(Would value comment from other WG members)


Charlie Abela wrote:


> I am trying to parse some DAML with the validator. The parsing of this 
> file used to give no complaint except that lately I am being faced with 
> this error: Error: {W130} Base URI is "", relative URIs left as relative 
> and I can?t figure out why?


Also this example from Art Barstow:

<rdf:Description rdf:ID="Profile">
<dc:title>World Wide Web Consortium</dc:title>
</rdf:Description>

generating the same error.

At some point I upgraded ARP to correctly identify the use of relative URIs 
in documents given with relative URIs as a problem.
The RDF graph uses absolute URI refs, and if no absolute URI can be 
established then there is an issue. Whether this is a warning or an error 
depends on the use case, and ARP supports either. The validator I believe 
runs in strict mode, and so most problems are treated as errors.

Recently the validator has had the ARP engine upgraded. At which point this 
behaviour was introduced.

I agree that it is a bug in the validator, since while no base URI can be 
determined for text pasted into a web form, it is unhelpful to complain 
about this. It is however not a bug in a compliant parser.

I suggest one of the following fixes in the validator code:
a) specify an arbitrary base URI instead of ""
or
b) tell ARP to ignore this condition
   setErrorMode(
      ARPErrorNumbers.WARN_RESOLVING_URI_AGAINST_EMPTY_BASE,
      ARPErrorNumbers.EM_IGNORE );

Personally I think option (b) is better.

A workaround until the validator is updated is to have the file to be 
tested as web accessible and use the validate URL option.

Jeremy