Re: [Json] Working Group Last Call on draft-ietf-json-text-sequence

Carsten Bormann <cabo@tzi.org> Sat, 24 May 2014 17:02 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Subject: Re: [Json] Working Group Last Call on draft-ietf-json-text-sequence
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On 23 May 2014, at 08:53, Martin J. Dürst <duerst@it.aoyama.ac.jp> wrote:

> it's not too difficult to parse the delimiters separately and only have the values parsed by a JSON parser

Indeed.  I continue to believe that this is the only reasonable way to operate on sequences of JSON instances.
Either

1) use a delimiter that cannot occur in JSON (staying in UTF-8 with ASCII control characters as in NUL, FF or RS; or breaking out of UTF-8 as in using 0xFF bytes);
2) use LF as the delimiter, and remove the LFs from the JSON instances.

Using LFs as inter-stream delimiters, while also retaining their insignificant whitespace role within JSON instances, strikes me as the most complicated way to approach this problem.
There may be practical reasons to use this most-complicated way, but it seems suboptimal to standardize on it.

(I’m not a big fan of wrapping separate JSON instances in outermost JSON arrays for the kinds of applications addressed here.
This can obviously already be used for those cases where it works (no need for concatenation, no need for resilience), but except in those cases where a combined JSON instance had been the right thing to use in the first place, it combines all the same problems of dual-use LFs with the need to add wrapping brackets.)

Grüße, Carsten