[apps-discuss] Questions about Structured Syntax Suffixes (SSS)

Mark Nottingham <mnot@mnot.net> Thu, 24 May 2012 01:35 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Date: Thu, 24 May 2012 11:35:37 +1000
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Subject: [apps-discuss] Questions about Structured Syntax Suffixes (SSS)
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I apologise if this has already been discussed, but this list has become nearly unreadable recently.

<http://www.ietf.org/id/draft-ietf-appsawg-media-type-suffix-regs-01.txt> motivates SSS with:

2.  When to Use these Structured Syntax Suffixes

   Each of the Structured Syntax Suffixes defined in this document is
   appropriate for use when the media type identifies the semantics of
   the protocol payload.  That is, knowing the semantics of the specific
   media type provides for more specific processing of the content than
   that afforded by generic processing of the underlying representation.

   At the same time, using the suffix allows receivers of the media
   types to do generic processing of the underlying representation in
   cases where

      * they do not need to perform special handling of the particular
      semantics of the exact media type, and,

      * there is no special knowledge needed by such a generic processor
      in order to parse that underlying representation other than what
      would be needed to parse any example of that underlying

Question: Is this actually useful in practice? I.e., what are the real-world use cases for SSS?

We started this experiment with +xml, and I'm not aware of much software that uses that suffix to great advantage (please educate me if I'm overlooking something).

One might imagine an editor to hint the convention used for the content, so that it can (for example) use an XML or JSON mode, but editors key off of filename extensions and magic, not media types.

What else is there?

I'm not debating that humans might find it satisfying to see the underlying formatting convention / metamodel surfaced in the media type, but I haven't seen much discussion of how machines will use this.

Question: So, if we were to invent a "profile" of JSON or XML that, for example, added linking conventions, maybe some other syntactic sugar, would that be suitable for registration as a suffix?

Question: Several of the proposed suffixes are effectively alternate encodings for the same data (e.g., fastinfoset, xml, wbxml), or very similar data. When I register a new media type, am I expected to register all of them?


Mark Nottingham   http://www.mnot.net/