- From: Jean-Jacques Moreau <moreau@crf.canon.fr>
- Date: Wed, 16 Jan 2002 16:09:02 +0100
- To: Christopher Ferris <chris.ferris@sun.com>
- CC: Martin Gudgin <marting@develop.com>, Marc Hadley <marc.hadley@sun.com>, XML dist app <xml-dist-app@w3c.org>
.. only insofar as basic types are concerned, as far as I understand. Jean-Jacques. Christopher Ferris wrote: > Only if one wanted to leverage the internal subset, > other than that, you could treat them in the same > manner as href and id. It would certainly be much > more convenient for implementations that did choose > to leverage DTD processing. Given that we're talking > about encoding, which leverages XML Schema types, it > is pretty clear to me that we're also imposing schema > processing anyway, no? > > Cheers, > > Chris > > Martin Gudgin wrote: > > > 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 10:10:44 UTC