RE: Information hiding?

On Thursday, February 28, 2013 8:56 PM, Nick Gall wrote:

> That said, one of the few powerful general principles for
> factoring interfaces into "modules" whose components are
> more likely to change at the same rate comes from the
> AWWWv1: http://www.w3.org/TR/webarch/#orthogonal-specs.
> "Identification, interaction, and representation are
> orthogonal concepts, meaning that technologies used for
> identification, interaction, and representation may evolve
> independently." Or as I like to put it: IFaPs (Identifiers,
> Formats, & Protocols) should be as loosely coupled as possible
> because they are likely to change at different rates. Protocols
> change the slowest, identifiers next, and formats the most quickly.

Yeah.. that's one of the aspects that is still not 100% clear to me. (Most)
media types not only define a serialization (representation) format but also
interaction models and sometimes specific semantic. Some are domain-specific
(to various degrees) while others are completely generic.

I tend more towards the use of completely domain-agnostic media types. Of
course, such media types need to provide some mechanism to express concrete
semantics (and thus hypermedia controls). The form doesn't really matter..
whether, e.g., XML-namespaces are used or a profile is associated with a
JSON file (preferably as media type parameter so that it's usable in conneg)
doesn't make a difference. I think this separation of concerns makes it much
easier to evolve systems in the long term since the parts may change at
different rates.

Maybe Roy could share his view on this as well.. I know he ran out of time
doing so a couple of years ago :-)


Thanks a lot,
Markus


--
Markus Lanthaler
@markuslanthaler