Re: IDREF vs HREF for graph edges in SOAP encoding

----- Original Message -----
From: "Edwin Ortega" <ortegae@wns.net>
To: "Martin Gudgin" <marting@develop.com>; "Marc Hadley"
<marc.hadley@sun.com>; "XML dist app" <xml-dist-app@w3c.org>
Sent: Wednesday, January 16, 2002 1:25 PM
Subject: Re: IDREF vs HREF for graph edges in SOAP encoding


>
> ----- Original Message -----
> From: "Martin Gudgin" <marting@develop.com>
> To: "Marc Hadley" <marc.hadley@sun.com>; "XML dist app"
> <xml-dist-app@w3c.org>
> Sent: Wednesday, January 16, 2002 5:55 AM
> Subject: Re: IDREF vs HREF for graph edges in SOAP encoding
>
>
> > I may be missing some context for this discussion but...
> >
> > Wouldn't using IDREFs *REQUIRE* DTD or Schema processing of SOAP
messages?
> >
> > Gudge
> >
> > ----- Original Message -----
> > From: "Marc Hadley" <marc.hadley@sun.com>
> > To: "XML dist app" <xml-dist-app@w3c.org>
> > Sent: Thursday, January 10, 2002 2:28 PM
> > Subject: IDREF vs HREF for graph edges in SOAP encoding
> >
> >
> > > All,
> > >
> > > On last nights telcon, Jacek and I took an action to start discussion
on
> > > the list about the merits of using IDREFs instead of generic HREFs for
> > > representing graph edges in the SOAP encoding.
> > >
> > > Attached is a table and commentary in HTML format listing a number of
> > > problems and issues concerned with the use of links as graph edges.
> > > Possible solutions are also shown for the two cases: graph edges as
> > > IDREFs or generic hrefs.
> > >
> > > Note that switching to IDREFs for graph edges does not preclude use of
> > > arbitrary links in encoded data. The switch only affects the kind of
> > > links used for encoded graph edges.
> > >
> > > Comments, flames, etc ?
> > >
> > > Marc and Jacek.
> > >
> > > --
> > > Marc Hadley <marc.hadley@sun.com>
> > > XML Technology Centre, Sun Microsystems.
> > >
> > > Jacek Kopecky <jacek@systinet.com>
> > > Senior Architect, Systinet (formerly Idoox)
> > >
> > >
> > >
> > >
> >
> >
>
> --------------------------------------------------------------------------
> --
> > ----
> >
> >
> > > Problems of hrefs vs. IDREFsProblems of hrefs vs. IDREFs
> > >      Problem Description Solution
> > >
> > >       IDREF HREF
> > >       1 Type of Node.  Currently the type of a node is specified using
> > xsi:type either explicitly or via a schema. This may not be the case for
> the
> > targets of external links. No change required. Remove the requirement
that
> > all values are typed, possibly adding other means of deriving the
> xsi:type,
> > e.g. from the resources MIME type.
> > >       2 Dereferencing When, or if, to attempt to dereference links.
All
> > graph edges are internal to the envelope. Therefore deserialisation
> > MUST/SHOULD dereference all links, any failure MUST generate a fault.
Some
> > graph edges may be external to the envelope. Deserialisation layer
> > MUST/SHOULD dereference internal links, MAY dereference external links
and
> > MAY/SHOULD/MUST fault when an link is not dereferenceable. Should the
> > faulting semantics be different for internal and external graph edges ?
> > >       3 Representation of external data in programming languages
> Internal
> > data with xsi:type is mapped naturally into programming language types,
> how
> > about external data? Not applicable. The implementation represents
binary
> > data in byte arrays or streams, XML data is represented as usual.
> > >       4 Serialising internal vs external links. During serialisation,
> the
> > SOAP processor has to decide what to include as internal content and
what
> is
> > left as an external resource. Not applicable. Either the SOAP processor
> has
> > to be told or has to have some ad-hoc rules.
> > >       5 Distinction between internal and external links The SOAP
> processor
> > has to be able to work out which links are internal and which are
> external.
> > Not applicable. SOAP processor has to implement logic based on the URI
> > schemes supported.
> > >       6 Full implementation of external link support in core. If
> external
> > links are permitted in the encoding then every generic SOAP processor
must
> > be able to handle them. Not applicable, any external links are just node
> > values. External link support required.
> > >       7 Support for SOAP with attachments Currently the SOAP with
> > attachments specification uses the href attribute to refer to
attachments
> > from within the envelope. A new higher level construct is required, e.g.
:
> > >       <parameter xsi:type="soapatt:att">
> > >           cid:....
> > >       </parameter>
> > >
> > >       i.e. SOAP with attachments support is layered on top of the core
> > encoding.
> > >      No change required
> > >
> > > Remarks
> > > Only the problem no. 2 requires some added language in case we should
> > choose IDREFs and that language is IMHO crisper and less vague (prone to
> > misinterpretation) than the current text for the href case.
> > >
> > > So actually going with hrefs requires us to specify a lot (solving
> > problems 1, 2, 3, 4, 5) and results in more complicated implementation,
> > while going with IDREFs requires us to change/specify a relatively
little
> > (2, 7) and the implementation is simplified. By the way, we consider the
> > change to attachments a cleanup change.
> > >
> > >
> >
> >
>
>

Received on Wednesday, 16 January 2002 14:07:36 UTC