[topicmapmail] Should resourceData have a MIME type?

[Nikita Ogievetsky]

Thinking about this issue again I must say that neither occurrence type, nor
scope, nor variant (which is not there yet) are the proper syntactical
places
for expressing resourceData MIME type.
I am saying this because all off the above allow expressing properties of
occurrence assertion. And MIME type is the property of the resource itself,
not occurrence!

To go around this one might create an association between all "text/html"
reified reourceData and "text/html" MIME type.
(Facets were a better instrument.)
And yes, the proposed by Tom optional MIME attribute on the resourceData is
a nice syntactic sugar solution.
Note that when parsed both solution will lead to the same graph.
It is just that associations are there for you now.

Tom said:
> > This practice makes a lot of sense, but the application has no way to
know
> > that one particular occurrence is going to have markup and another is
not.
> > It is not always easy to detect markup, especially the type of the
markup.
> >
> > Presumably for a resourceRef, the application can find out the MIME type
> > when it retrieves the resource, but not so for resource data.
> >
> > It would be clumsy to define different occurrence types to hold
different
> > types of resource data.  It would be very complex to specify each
instance
> > as being of some type that holds the right data type.
> >
> > It would be very simple to add an optional attribute to resourceData
that
> > would specify the MIME type.  Then my app could get an occurrence of
Kal's
> > data, discover that it is intended to be HTML, and display it
accordingly.
> > Even inline images could be included, along with the other MIME types.
> >
> > This would be so useful and so simple - and backwards compatible - that
I
> > urge its adoption in the next version of the ISO standard.
> >

Kal said:
> This is a neat solution and nicely self-contained. I guess that the
> alternative solution is to allow varients of occurrences and define PSIs
for
> media types so that meda-type topics could be used as parameters to the
> occurrence variants.
>
> Nikita's proposal of using scope to express the occurrence media-type
feels
> (to me) as an overloading of the scope principle. I feel that the
> relationship of the media-type to the resource is a meta-data relationship
> rather than a context relationship.

Kal, it feels to me that way too. I proposed it as a solution that works
with the current DTD. Now I am in favor of the other one (see above).

--Nikita

Nikita Ogievetsky, nogievet@cogx.com;
Cogitech Inc.        http://www.cogx.com
Topic Maps Tutorials and Consulting.
phone:  1 (917) 406 - 8734