Re: Question about annotation IDs

> On 31 Aug 2016, at 14:58, Shane McCarron <shane@spec-ops.io> wrote:
> 
> So.... while I don't think the spec says this, I assume that the ID property of an annotation MUST be an absolute IRI.
> 
> If that is not the case... I can change the server tests to impute the absolute IRI based upon... something.  But I don't know what that something should be.  Probably if the ID starts with a '/' it is relative to the scheme + hostname + port we are referencing for the collection, and if it doesn't start with a '/' it is relative to the container URL.

Hm.

- The RDF 1.1 abstract syntax does say that a URI must be absolute[1].
- JSON-LD  says "A relative IRI is an IRI that is relative to some other absolute IRI. In JSON-LD all relative IRIs are resolved relative to the base IRI."[2] and then describes the base IRI-s in [3] referring to @base[2] and, in the absence of it, it is relative to the document.

However, the model does not aim at depending on JSON-LD too much; I am not sure whether it would be acceptable to use the @base (note that the JSON-LD spec says that a @base in an externally referenced context file is ignored). What this leaves us is that a relative URI is to be dereferenced with the full collection of annotation as a base URI, following the URI spec. This is where JSON-LD leads us.

However, I always regarded every annotation as some sort of a self-standing entity, ie, relying on a higher level resource URI is shaky. Ie, I think it is perfectly fine if we consider the ID property as always being an absolute URI. If we agree on this, this clarification should be added to the spec…

Ivan

[1] https://www.w3.org/TR/rdf11-concepts/#h3_section-IRIs
[2] https://www.w3.org/TR/json-ld/#h3_iris
[3] https://www.w3.org/TR/json-ld/#h3_base-iri <https://www.w3.org/TR/json-ld/#h3_base-iri>

> 
> Anyway, help?
> 
> --
> Shane McCarron
> Projects Manager, Spec-Ops


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Ivan Herman, W3C
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