RE: ATOM representation of search result facets
"Rushforth, Peter" <[email protected]>
| Newsgroups | gmane.comp.web.services.rest |
|---|---|
| Message-ID | <1CD55F04538DEA4F85F3ADF7745464AF1AE4F490@S-BSC-MBX1.nrn.nrcan.gc.ca> |
Hi Mark, Thanks for replying. > On Wed, Sep 5, 2012 at 8:09 AM, Rushforth, Peter > <[email protected]> wrote: > > My understanding is that application/atom+xml describes > atom *without* > > extensions. If you put extensions in, to *any media type*, > via either > > new markup or even changing the meaning of standard atom > markup, you > > should change media types, because it is the media type > which names / > > describes the preferred semantics of the message, and it is the > > message metadata which is the most authoritative on the web: > > That's not the case. It may well be the case for some - > text/plain comes to mind - but the majority of widely used > media types are designed well enough to accommodate > non-breaking extensions (where their introduction doesn't > affect the meaning of the core content). IOW when served with that media type messages are understood as that media type. If a client/processor is looking for the extended semantics how does it request them? > > That said, there's some ambiguity here with regards to when > it makes sense to use a different (or new) media type. An SVG > document wrapped in "<html><body>" wouldn't be very useful > served with the text/html media type, for example. ??: http://www.w3schools.com/html5/html5_svg.asp > But an > Atom document with a single entry extension from a foreign > namespace is still an Atom document because the spec > specifically accommodates such an extension; it should use > application/atom+xml. I agree that it _can_ use application/atom+xml, but in order to convey extended semantics, paging for example, it would need to use a different media type, application/atom+xml;type=feed in the paging case. > In between those two extremes, the > decision depends upon the specifics of the extensibility > features of the > type(s) in play, the importance and quantity of extended vs. > core content. I don't think its a question of quantity, more of importance. And importance is subjective. If the extended semantics is important to a client, it will be requested, with Accept:. If not, it won't. But if the extended semantics is just served with no signals for desire or of delivery, and clients actually do end up using the extended semantics, that is out-of-band coupling of the nth degree IMHO. > > Only the publisher knows what the content means, so they get > to decide which media type to use. I believe that it is the published definition of the media type which is important, not the content. A jpeg of my cat is not the same content as a jpeg of a supernova, but they both may have the same media type definition. On the application tree, application/json or application/xml would be sufficient for almost everything. But they aren't, so we invent new media subtypes to describe the markup. Atom is one, but I don't think it stops there, not by a long shot. YMMV Peter