RE: [xri] updated proposed XRI 1.1 ABNF

["Dave McAlpin" <Dave.McAlpin@epok.net>]

Mike,

You do a fair amount of work to avoid ":" in authority (in xri-subseg-nc
and xri-subseg-nc-od). I think we're doing this because ":" has defined
semantics in the authority part of a URI. We don't disallow "@",
however, which also has a defined meaning for URI authorities, and we
don't disallow "@" and ":" in xrefs that appear in an XRI authority.
Consequently we have to do some escaping in authority when we go from
XRI normal form to IRI normal form to blind out "@" and ":" (along with
other characters like "/", "?" and "#" that appear in xrefs).

Since we're already allowing ":" in an XRI authority via xref, along
with several other characters that can't appear in a URI authority, I'm
wondering if we shouldn't go ahead and define authority subsegments in
terms of xri-pchar rather than xri-achar and handle ":" in the transform
to IRI normal form.

Dave

> -----Original Message-----
> From: Lindelsee, Mike [mailto:mlindels@visa.com]
> Sent: Wednesday, September 22, 2004 3:20 PM
> To: xri@lists.oasis-open.org
> Subject: RE: [xri] updated proposed XRI 1.1 ABNF
> 
> Attached is an updated version of the 1.1 ABNF.  A number of issues
were
> raised and discussed on the editor's call yesterday.  The new ABNF
> addresses all but one of those issues.  To summarize, the issues (and
> their resolutions) were as follows.
> 
> 1.  Concern about allowing the "//" at the beginning of an XRI to be
> optional.  Resolution: "//" is never optional.  Absolute XRIs begin
with
> "xri://" or with either an xref or gcs character.
> 
> 2.  [This is the issue that is still open.]  Should multiple xrefs and
> characters be allowed to be mixed in a subsegment in the path (the
part of
> an XRI after the first "/" and before a fragment or query)?  E.g.,
> xri://@foo/(bar)abc(xyz).  The issue at stake here is should the path
be
> left as flexible and loosely-defined as possible, or should the XRI
> specification make stronger statements about the syntax and semantics
of
> segments or sub-segments in the path (and what should that syntax and
> semantics be).
> 
> 3.  Should production names that refer to sub-segments have "sub" in
their
> names or is it ok to just call them "segment" productions?
Resolution:
> replace "segment" in the appropriate productions with "subseg".
> 
> 4.  Support for authority-less XRIs.  E.g., xri:/foo.  Resolution:
Remove
> support for authority-less XRIs.
> 
> 5.  Should we follow 2396bis and disallow "[" and "]" in the query and
> fragment productions? Resolution: Follow 2396bis.
> 
> Two errors were also found in the ABNF and have been corrected.  The
first
> allowed an XRI authority that started with an xref to be followed by
> arbitrary characters (e.g., xri://(@foo)abc).  The second allowed a
> subsegment in an XRI authority to be composed of an arbitrary number
of
> characters and xrefs (e.g., xri://@foo.(@bar)abc(@xyz)def).  This
second
> error is related to issue number 2 above, but such behavior was never
> supposed to be allowed in the authority part of an XRI.
> 
> Mike