- From: <Noah_Mendelsohn@lotus.com>
- Date: Thu, 21 Jun 2001 11:48:18 -0400
- To: xml-dist-app@w3.org
- Cc: jcowan@reutershealth.com, pgrosso@arbortext.com
My sincere apologies. The note I sent yesterday referred to a very old draft of the Infoset CR, the result of following a bad bookmark in my browser, and perhaps not remembering that Infoset had been in (or near) CR so long and had changed so much. (I thought I had doublechecked which draft I had, but obviously not carefully enough). The new Infoset draft makes significant strides toward dealing with the concern raised yesterday. For completeness, here is a redraft of yeserday's note, ending in a recommendation that XMLP do nothing formally, and leave any changes to the discretion of the Infoset team. Again, my apologies for the confusion, and thank you to David Ezell for noticing and warning me. =====REDRAFT OF YESTERDAY'S NOTE FOLLOWS ========= Quick background for those not in the Protocols WG: there has been some semi-formal discussion in the protocols WG as to whether it might be appropriate to adopt, in one of various possible ways, XML Infosets as the fundamental means of describing an XMLP message. Without going into details, the general idea would be to have XMLP specify the contents of messages in the form of Element and Attribute Information items. Particular bindings, such as the http binding, could then decide on the exact representation of the XML on the wire (ordinary well-formed, compressed, encrypted, something else, etc.). Anyway, on an XMLP WG teleconference today I was asked to post this note to the dist App list. The purpose of this note is not primarily to start a discussion of the merits of the above proposal: indeed, the WG is still considering whether and in what form to make such a proposal. Rather, I have been asked to mention a specific aspect of the Infoset Candidate recommendation draft that is perhaps less than ideal for our purposes. Specifically, the CR Infoset draft states [1]: "This specification defines an abstract data set called the XML Information Set (Infoset). Its purpose is to provide a consistent set of definitions for use in other specifications that need to refer to the information in a well-formed XML document [XML]. [...] "An XML document has an information set if it is well-formed and satisfies the namespace constraints described below. There is no requirement for an XML document to be valid in order to have an information set." The potential problem is that this text, though arguably a bit ambiguous, strongly suggests that well formed documents come first, and then Infosets must be derived from them. There are important use cases, such as in XMLP, in which XML infosets should describe documents that may not initially (or ever) exist in the form of a sequence of Unicode characters with "<...>" syntax. As a trivial example, consider an empty DOM to which a program adds element and attribute nodes. Surely there is an Infoset, but no "<...>". Indeed, this is likely to be the common case for the sender of an XMLP message. If the binding sends an encrypted form, there need not at any time be "<" form or a conventional parser at the receiver; the SOAP processor might go directly from encrypted to SAX/DOM/etc. at the receiving end. The specific question on the table in yesteray's call was: should the XMLP WG send a comment to the Infoset (core) group recommending a change to the introduction of the XML Infoset candidate rec.? An important section [2] was added between the Infoset draft I referenced yesterday and the one that's current: "Synthetic Infosets This specification describes the information set resulting from parsing an XML document. Information sets may be constructed by other means, for example by use of an API such as the DOM or by transforming an existing information set. " This largely deals with the concern (someone pointed this out on the call yesterday, but I couldn't find the reference because I was looking in the wrong draft.) My personal feeling is that the Intro [1] is slightly out of sync with [2], but I con't think that rises to the level of something the XMLP group should be taking on as a formal response. So my net is, with apologies for any confusion caused, just let it go. I have cc:'d John Cowan and Paul Grosso, so the Infoset team is aware that at least one of us had some confusion reading the intro. I think it should be at their editorial discretion as to whether any minor cleanup is in order for a Recommendation. Clearly the intent of the CR draft is correct. I presume that anyone in the XMLP WG who disagrees with my recommended disposition will speak up. Thank you. [1] http://www.w3.org/TR/xml-infoset/#intro [2] http://www.w3.org/TR/xml-infoset/#intro.synthetic ------------------------------------------------------------------------ Noah Mendelsohn Voice: 1-617-693-4036 Lotus Development Corp. Fax: 1-617-693-8676 One Rogers Street Cambridge, MA 02142 ------------------------------------------------------------------------
Received on Thursday, 21 June 2001 11:54:34 UTC