IRC log of xsd-user on 2005-06-22

Timestamps are in UTC.

00:02:02 [plh]
posters are available online, starting at
00:02:17 [plh]
(I didn't rotate them but the exif bit is there)
00:08:03 [dezell]
Candidate topics for tomorrow:
00:08:09 [dezell]
Schema profiles (13)
00:08:18 [dezell]
LC124 Versioning (6)
00:08:25 [dezell]
Coconstraints (6)
00:08:29 [dezell]
Test suite (4)
00:08:39 [dezell]
Wild card deficiences (4)
00:08:46 [dezell]
Inconsistent Versioning (2)
00:08:55 [dezell]
Henry Speak (2)
00:09:00 [dezell]
Formal Notation (1)
00:09:13 [dezell]
Extend only at end (2)
00:09:25 [dezell]
Anonymous types lack identity (2)
00:09:35 [dezell]
Graph semantics (2)
00:09:39 [dezell]
UPA (4)
00:09:45 [dezell]
Schema location hints (2)
00:09:56 [dezell]
XML schema 1.1 -- just say no (2)
00:10:18 [dezell]
Extensions of enumerations (2)
00:10:26 [dezell]
MSM: suggest we use the hum method for voting.
00:12:09 [dezell]
MSM: note that "Henry Speak" is not the only source of complexity in the Rec.
00:12:27 [dezell]
s/Henry Speak/unwarranted complexity in the rec/
00:15:06 [dezell]
Additional topics:
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Validation (1)
00:15:22 [dezell]
Code generation (2)
00:15:27 [dezell]
Round tripping (1)
00:15:36 [dezell]
Annotations for data mapping (3)
00:15:42 [dezell]
Business level validation (1)
00:17:35 [dezell]
SZ: we should discuss the style of the spec.
00:17:47 [dezell]
PD: to me, profiles seems more important.
00:17:48 [plh]
00:18:22 [dezell]
JM: yes, suggest profiles is less techical, more fruitful
00:18:47 [plh]
i/NM: is it a compatible change/scribeNick: MSM
00:19:03 [dezell]
NM: we need to be clear what success for this group is. I think it's to give guidance to W3C on how to recognize success.
00:19:10 [plh]
i/Michael: can you define/scribeNick: plh
00:19:52 [RRSAgent]
I have made the request to generate plh
00:20:27 [dezell]
CF: we should focus discussion on things that could be actionable coming out of the workshop.
00:21:16 [dezell]
CF: if we're going to recommend profiles, (e.g.), who should be involved in defining them.
00:22:02 [dezell]
MSM: I see another more radical clump.
00:22:11 [dezell]
... clump 1 -- ways to improve the language
00:22:24 [dezell]
... clump 2 -- ways to improve things without changing the language
00:23:05 [dezell]
... clump 3 -- profiles (improve things without changing the language forward)
00:23:43 [dezell]
... this work can say, for the customers we stand for here, these things might be important enought to warrant a breaking change.
00:24:01 [dezell]
... providing input to the Schema WG of the relative value of these various options.
00:25:18 [dezell]
PB: i agree, and I would choose: clump 2, and then clump 1.
00:26:14 [dezell]
AM: one other item might need to be included which is Schema 1.1.
00:27:06 [dezell]
SZ: I don't understand what "improving life" means.
00:27:26 [dezell]
MSM: for example, I'd class something in clump 2 "improve the accessibility of the test suite".
00:28:16 [dezell]
MSM: the schema test suite is >not< a conformance test. It's possible to view improving the test suite as more than just clarifying the spec.
00:29:03 [dezell]
SZ: won't the test suite become a de facto conformance test?
00:29:15 [dezell]
(scribe notes general negative grumbling...)
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00:32:52 [dezell]
DP: I think the green list (the clumps) are sub agendas underneath every blue topic.
00:33:09 [dezell]
MSM: e.g. you can't fix UPA without changing the rec.
00:33:20 [dezell]
DP: ask XML Spy.
00:33:38 [dezell]
DP: add a category, what can be achieved by ignoring the spec.
00:33:51 [dezell]
MSM: the chairs will now turn our backs and judge by your humming.
00:34:30 [dezell]
Schema Profiles - medium loud
00:34:44 [dezell]
LC124 Versioning --
00:35:00 [dezell]
medium loud
00:35:08 [dezell]
co constraints - very soft
00:35:12 [dezell]
test suite - soft
00:35:36 [dezell]
wildcard deficiences - medium
00:35:45 [dezell]
inconsistent versioning methods - none
00:36:00 [dezell]
scribe gives up.
00:37:11 [holstege]
scribe is wise
00:38:10 [dezell]
we have 8 winners.
00:38:32 [dezell]
(general consensus that organizers have enough info to proceed.)
00:38:59 [dezell]
MSM: program committee will convene briefly when we adjourn.
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00:44:33 [jonc]
does anyone need a lift back to the Sofitel?
00:45:46 [dezell]
meeting ends at 5:42 PDT
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logging to
15:34:03 [plh]
Meeting: XML Schema 1.0 user experience report
15:34:17 [plh]
Chair: Paul Downey, Michael Sperberg-McQueen
15:34:30 [plh]
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15:38:24 [ht]
I gather that Paul D has posted photos of your whiteboard to flickr -- did the meeting agree to do this?
15:38:26 [ht]
15:38:49 [jonc]
Topic: Matrix of user experience reports. Paul Byron
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15:40:17 [jonc]
First we review the agenda today....
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jonc changes to scribe ....
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Topic: Matrix of user of experience reports. Paul Byron
15:45:38 [scribe]
PB created summary of all reports
15:46:11 [scribe]
Stand out observation: Too many people have wanted too many things from schema from day1
15:46:38 [scribe]
One mans 80 is another mans 20
15:47:15 [scribe]
e.g. redefine either bread and butter or completley useless
15:48:23 [scribe]
we all tend to be selfish in defining what goes into the spec
15:49:53 [scribe]
Equally number of people indicated no change was needed
15:50:21 [scribe]
StevenZ you are being unfair in the reprimand
15:50:35 [scribe]
PB: deliberately!
15:51:22 [plh]
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15:52:42 [pauld]
rrsagent, where am i?
15:52:42 [RRSAgent]
15:53:02 [pauld]
rrsagent, make logs member visible
15:53:02 [RRSAgent]
I'm logging. I don't understand 'make logs member visible', pauld. Try /msg RRSAgent help
15:53:32 [cferris]
paulb: haven't heard anything new here... these issues have all been expressed before
15:54:09 [pauld]
rrsagent, please make logs member-visible
15:54:16 [scribe]
Standards writing is hard. Compromise is essential. People have to realise that you got to bend
15:55:14 [scribe]
Cannot satisfy everyone with this language. As a group we are at crossed purposes with each other
15:56:24 [scribe]
PB as editor and user knows we have to listen to each other and achieve solutions together
15:56:58 [scribe]
PB asks audience Is characterisation correct?
15:58:14 [scribe]
Holstege: There are very difficut problems here. something has to give
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16:00:00 [scribe]
StevenZ: 2 issues. 1) vendors implementation in their tools. vendors say impossible to have consistent implementation
16:00:41 [dorchard]
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16:01:27 [holstege]
mh's point more like: you cannot have tight idiomatic code generation by tossing out features that support versioning/extensibility plus versioning/extensibility plus universal feature support in all tools, all at the same time.
16:01:44 [scribe]
StevenZ. Onus is on committee to define what is correct
16:02:52 [scribe]
NoahM: Can only go so far. Can say what is or isn't an XML document, can't say what software can be used.
16:05:18 [scribe]
Noah: W3C normally stays out of specifying what is conformat.
16:06:19 [scribe]
DanVint: That is a reasonable position but( e.g) many tools claim to be an XML tool while supporting very little
16:06:41 [scribe]
Noah: WS-I doesn't really do this either
16:07:29 [scribe]
Dan: not looking for W3C to certify everything but need an indication of what level of support is being offered.
16:08:49 [cferris]
I think that a comprehensive test suite that was an accurate reflection of the spec (even if it didn't provide complete coverage) could go a long way to providing a means by which the market can police itself with regards to conformance
16:08:53 [scribe]
Dezell: profiles have been proposed. We need a concept map that defines the problem space wrt diff languages
16:09:17 [cferris]
of course, that would also require that the w3c "market" this concept... something along the lines of what we have done in WS-I
16:09:18 [scribe]
PaulD: but schema has already profiled all the languages in the world .....
16:09:27 [stevenzenith]
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16:09:44 [cferris]
I would be glad to discuss this with staff or the WG at their pleasure
16:10:17 [scribe]
Topic: Panel discussion
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16:12:41 [scribe]
Panel = Ashok, PaulB, Mary H, Noah M, MSMQ, David Ezell;Leonid, Tony
16:14:32 [scribe]
Dezell: quick intro to WG. and NACS (national assoc convenience stores) they care about standard = saving money
16:15:14 [scribe]
sometime NACS members ask why competitive advantage is 'given away' in a standard?
16:15:51 [cferris]
two things that NACS cares about are versioning and co-constraints
16:15:55 [scribe]
So huge investment in XML schemas and know that it is not good enough.
16:16:23 [cferris]
s/two things/dezell: two things/
16:16:44 [dezell]
16:17:01 [cferris]
URI above is charter for XML Schema WG
16:17:27 [scribe]
WG needs involvement. You!
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16:17:44 [stevenzenith]
note: I did not mean to suggest the W3 should tell software vendors what software to write or how to write it - my point was rather that the committee is responsible for enabling conformable tools through the standard
16:17:45 [noah]
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16:18:04 [scribe]
Goal is to prepare vfersion 1.1 of the schema rec
16:18:15 [cferris]
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16:19:27 [dorchard]
methinks "1.1" will be an inappropriate name. Hard to see how backwards compatibility will be maintained and meet the versioning goals, particularly if wildcards are changed.
16:19:29 [scribe]
We will produce document on compoenent designators bring us close to the semantic web
16:19:43 [cferris]
16:21:54 [scribe]
DE will later tell about the rules of engagement.
16:22:48 [cferris]
s/Goal is to/David E reviews WG charter. Goal is to/
16:23:47 [scribe]
Changes to component model countenanced to smooth things out but only one change (addition of decimal type) has been made so far
16:24:23 [cferris]
s/decimal type/precisionDecimal type/
16:27:11 [scribe]
JM: is the 'formal description of XPATH' still active?
16:27:19 [scribe]
Panel:Answer no lack of resources has meant this is on the back burner
16:28:26 [pauld]
thinks formal description would be of most value if you could change the spec as a result. it's too late now it's out there in so much code
16:28:31 [cferris]
s/of XPATH/of XSD/
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16:29:16 [pauld]
though a formal description which could generate test cases could be of value
16:29:40 [scribe]
MSMQ: basically members got enough from what was produced. It would still be a good thing ...
16:30:41 [scribe]
PaulD: calls time on this as it was not a topic for discussion.
16:31:14 [pauld]
stevez: small but important audience for formal description
16:31:43 [scribe]
MSMQ takes the floor to talk about comments
16:32:38 [scribe]
WG has error reporting procedure. Fixes for 1.0, changes for 1.1, clarification etc
16:32:53 [scribe]
Written procedure to follow linked off home page
16:33:53 [scribe]
Problem with collection of errata is co-ordinating changes with other grpups that may not have reviewed errata.
16:34:34 [scribe]
W3C approach is that errata are informative not normative
16:35:14 [scribe]
Last Nov 2nd edition of XML schema 1.0 with circa 150 changes
16:35:54 [scribe]
WG seeing problems that indicate vedors are still working off the old version
16:36:05 [stevenzenith]
so I heard the following: the formal specification work that was completed - and is apparently used in the formal work of XPath and XQuery is not supported by the committee because there is a mismatch between the specification and the published standard
16:37:50 [scribe]
CF: this is a common problem, bugs found... WG fixes bug... tells vendors but not seen as important enough to chnage delivery dates of software etc
16:38:39 [scribe]
CF: So what can we do to better provide for the community?
16:39:49 [scribe]
MSMQ: 2 things, in general WG position is to promote 1.0 answer unless 1.0 spec has a contradicion
16:40:57 [cferris]
each erratum should have test cases
16:40:58 [scribe]
MSMQ: Each erratum should have 1 or more test case
16:41:29 [scribe]
Would also be useful to have tool that examines schema
16:41:37 [pauld]
+1 to erratum specific test cases, before and after would be useful
16:41:54 [scribe]
Maybe not every erratum can be detected that way but most could
16:42:21 [scribe]
Dezell: WG did minute decision to have test cases for every errata......
16:43:39 [scribe]
PaulB: There is an alarming lack of documentation from vendors about what level of errata have been included
16:44:06 [scribe]
JM: wouldn't that just be noise from our point of view?
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Dezell: likes suggestion that submitters of errata are accompanied by test case assertions
16:46:05 [scribe]
Dezell: this will be covered later
16:46:49 [scribe]
Dezell: encourages everyone to read Processing XML 1.1 docs with XML schema 1.0 processors
16:46:57 [mnot]
16:47:42 [scribe]
dezell: Lots of discussion in this area eventually shelved thoughts of performance and just concentrated on what processor developer has to do too effect this
16:48:38 [scribe]
Ton: takes floor to talk about test suites
16:48:50 [scribe]
Ton = Tony
16:48:58 [dezell]
16:49:18 [plh]
16:49:45 [scribe]
There is a framework document for the test suites
16:50:53 [scribe]
Metadata includes location, what is being tested etc, submissions are public
16:51:51 [scribe]
Contributions to test suite open to everyone and encouraged
16:52:32 [scribe]
Process document describes process for dealing with tests.
16:52:50 [scribe]
First pass assesses that structure is correct
16:53:28 [scribe]
Then WG gives it 'acceptable' status and it is dsipalyed conistently with other etsts in the suite
16:54:34 [scribe]
One it is reviewed found to be error free it is given status of stable and publisised.
16:54:47 [scribe]
errors mean it is give a or 'disputed' status and goes back to the WG
16:55:36 [scribe]
Schema tests 1.0 compiled by Henry with major submission from Sun, microsoft, NACS
16:56:44 [scribe]
Leonid: test suite v. important tool for proving interop of implemetations
16:57:30 [scribe]
Leonid: but unfortunatley not required confrmance for vendors as it is with Java
16:58:17 [scribe]
PaulD: wrt Java are there specific tests for individual areas e.g. JaxB
16:58:48 [scribe]
Leonid: Yes but vendors must pass all tests
16:59:15 [scribe]
Dezell: how many test for 2.0 oftest suite?
16:59:28 [scribe]
Tony: several thousand.
17:00:22 [scribe]
Mary takes floor
17:02:55 [pauld]
Mary: SCD's identify components in the schema component model
17:03:14 [pauld]
waleed: so it's like XPath for Schema
17:03:32 [pauld]
Mary: you can use it to compare two schemas
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17:04:08 [pauld]
Marsh: can be used for layered spec, that's the use-case for WSDL component designators
17:04:18 [ErikJ]
17:04:47 [pauld]
noah: URIs for identification is a part of the webarch
17:05:03 [scribe]
Noah. New datatype in plan for schema 1.1
17:05:19 [scribe]
new decimal type to coexist with existing one.
17:06:03 [scribe]
original type not compatible with emerging IEEE ne
17:07:20 [scribe]
Differences. IEEE unifying Decimal and floating point in a single standard with similar semantics
17:07:31 [scribe]
Operations defined
17:07:48 [scribe]
Significant digits count ..
17:08:04 [scribe]
IEEE suggests storage formats
17:09:08 [scribe]
Ashok takes floor
17:09:35 [scribe]
XPATH strongly typed taking types system from schema 1.0
17:11:13 [stevenzenith]
precision decimal reference:
17:13:08 [scribe]
Waleed: are new types supported in XPATH
17:13:43 [scribe]
Panel: Yes, only introduced a type that they had in their hierarchy anyway
17:14:39 [scribe]
Waleed: does schema 1.1 have new namespace?
17:17:34 [scribe]
Noah takes floor to talk about versioning
17:17:36 [dezell]
17:18:01 [stevenzenith]
I asked if it was possible for xsd 1.0 to be a profile of xsd 1.1 - Noah pointed out some issues with base types that might make that a challenge
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PaulD: most WG conduct themselves in oublic but schema does not. Is that a problem for getting people involved?
17:19:04 [scribe]
Dezell: most of what we do feels public.
17:19:16 [scribe]
Dezell: could slow us down further
17:19:26 [dorchard]
An additional resource
17:19:43 [scribe]
Dezell; but with versioning public scrutiny is needed.
17:20:28 [scribe]
all kinds of ways that versions happen so looking at it in a bigger way.
17:21:09 [scribe]
Noah: (from slides) XML should be key to loose coupling
17:21:21 [dorchard]
there is the W3C versioning mailing list that is public
17:21:47 [scribe]
idioms for evolving languag vocaband schema not agreed
17:21:58 [scribe]
e.g. roles of namespaces
17:22:31 [scribe]
also disagreement over extension vs restriction
17:23:07 [scribe]
Use cases driving a lot of the WG analysis
17:24:05 [scribe]
WG has description of terminology and proposed mecahnisms
17:24:32 [scribe]
Noah has written white paper on evolving XML schemas
17:24:42 [plh]
Noah's slides ->
17:24:59 [scribe]
Document ed Dorchard and Norm Walsh referenced
17:25:28 [scribe]
Some basic principles:
17:26:10 [scribe]
clean support for repeated revisions (>20)
17:26:52 [scribe]
Versioning 'Sometimes Not Always' (SNA) tied to namespaces
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17:27:48 [scribe]
Don't presume constructs in instance docs (e.g. <extension>)
17:28:34 [scribe]
More controversial? .. forward/backward SNA required. Breaking changes happen
17:29:06 [scribe]
Umit: what is the issue here with breaking the rules?
17:31:02 [scribe]
StevenZ: are you arguing against arbitrary changes in schemas?
17:33:53 [scribe]
MSMQ: Noahs point is that creating a new version MUST make a schema processor 'die'
17:35:09 [scribe]
Noah: difficult thing is schema is a tool for the application, can not say what users will do. We are building a tool but trying not to bake the model into the tool
17:36:13 [scribe]
StevenZ: are you propsoing to make changes to schema language to enable schema to capture redefinition /deprecation of elements?
17:36:41 [plh]
17:37:01 [RRSAgent]
17:37:57 [scribe]
Noah: Principles continue....
17:38:17 [scribe]
Check/enforce compatibility in tools
17:39:10 [scribe]
Versions may or may not form sequence or tree
17:40:13 [scribe]
Revisions sometimes not always expressed as deltas
17:41:57 [scribe]
Restriction vs Extension. Base schema allows all future content
17:43:54 [scribe]
wildcards... validate future content, weak wildcards beat UPA problems, New wildcard matches: any elements not known about in this schema
17:44:13 [scribe]
Process decsion 2 minutes to finish off....
17:45:17 [scribe]
Extension.... base schema validates only version 1 content
17:46:22 [scribe]
but new processing nodes indictae which subset of content would have
17:47:21 [scribe]
StevenZ: uncomfortable with use of the term 'wildcard' here
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17:48:56 [scribe]
Dezell: Major minor use case. pulled from UBH covers the 'breaking change' scenario. describes schemas as the exist today
17:49:45 [scribe]
Dezell: 2nd use case. OO how do you serialize/deserialise object and how do you cope when things change
17:51:02 [scribe]
Dezell: 'Specialzsation' is need to create template schema
17:51:11 [cferris]
versioning use cases URI:
17:53:37 [scribe]
Dezell quickly decribes remaining use cases (link above) and invites review from particpants.
17:54:31 [dorchard]
FWIW, I plan on offering an evaluation compared to some Web services use cases.
17:54:32 [scribe]
Versioning presentation ends 10.55. Coffee break till 11.25
17:57:46 [ErikJ]
[Taking over as scribe]
17:59:57 [ErikJ]
Photos posted at
18:10:49 [plh]
scribeNick: ErikJ
18:11:23 [ErikJ]
Chair: Confirming the Agenda...
18:11:55 [ErikJ]
... Topics to be discussed based on yesterday's vote: Schema 1.1, Test Suite, Versioning
18:14:08 [ErikJ]
... Now is the appropriate time to bring up ideas about how to change the schema language
18:14:51 [ErikJ]
... Let's start with versioning
18:16:23 [ErikJ]
Paul B.: There have been a lot of discussions going on .. changing versions means changing namespaces
18:16:56 [ErikJ]
... other say it's different [bit buckets]. Agrees with Noah -- should not bake any of these ideas into the XSD spec.
18:16:56 [dorchard]
I disagree that changing versions always means changing namespaces.
18:17:36 [ErikJ]
... we should put hooks in so that processors can use their own rules
18:18:52 [ErikJ]
Paul was using the namespace change concept as an example only, BTW.
18:19:55 [ErikJ]
... Would anyone in this room be happy if the spec says the only legal schemas are version in one or two ways mandated by the spec?
18:20:50 [ErikJ]
q1: Could the W3C do a best practices doc?
18:21:12 [ErikJ]
Ashok: Someone *else* should do that work.
18:22:38 [ErikJ]
Dan Vint: Isn't there precedence that a new version = new namespace?
18:23:46 [ErikJ]
Paul B.: Maybe, but there is probably no one right answer.
18:24:10 [pauld]
s/Paul B:/PaulB:/g
18:24:38 [ErikJ]
18:26:10 [ErikJ]
DanVint: It's the only solution I can get to reliably work at this time.
18:27:00 [dorchard]
18:27:12 [ErikJ]
Umit: No one has an identification scheme to declare "this is the major verison", "this is the minor version", etc.
18:27:59 [dorchard]
The meaning of "Major" and "Minor" is the problem.. does "minor" mean "backwards compatible" change, "small software" change, "small document" change?
18:28:13 [dorchard]
re: xml 1.1
18:28:20 [dorchard]
and schema "1.1".
18:28:21 [cferris]
a namespace is just that, a space of names
18:28:34 [ErikJ]
holstege: There is a hole in the architecture in that namespaces are unrelated [values]
18:29:01 [pauld]
thinks namespaces are about ownership not just versioning
18:30:15 [ErikJ]
PaulD has a presentation about issue LC124
18:30:51 [mnot]
s/issue LC124/Web Services Description issue LC124/
18:31:14 [ErikJ]
PaulD: "Compatible Evolution"
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18:31:36 [ErikJ]
... XML is "yet another self-describing format"
18:32:07 [ErikJ]
... add optional stuff, don't delete stuff, don't change the meaning of stuff, communicate breaks in compatibiliy
18:32:11 [cferris]
URI for WSD WG LC124:
18:33:19 [jeffm]
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18:33:48 [ErikJ]
... LC124 -- Evolution is a *big* issue for web services, WSDL WG failed to engage the XSD WG, LC124 - versioning last-stand, Concrete Proposal
18:34:44 [ErikJ]
... Since we use schema to describe message exchanges, this is really a schema problem
18:35:34 [dorchard]
Options being discussed for LC124 at
18:36:14 [ErikJ]
... XML Schema 1.0 for Description -- 1. Description of content constructed by a sender, 2. description of content available for a receiver, 3. validating the format of amessage
18:36:24 [ErikJ]
s/amessage/a message/
18:37:20 [ErikJ]
... Versioning and XML 1.0 -- got to get it right in version 0, UPA and greedy xs:any make writing extensible schemas *tricky*, have to resort to dumb schema tricks
18:38:43 [ErikJ]
... Validate Twice (Henry Thompson's technique) -- 1. Validate document, 2. Prune PSVI elements marked "*[pe:validity()='notKnown']", 3. Validate pruned document.
18:39:23 [ErikJ]
... [going back to "XML Schema for 1.0 for Description] -- you can do point 3.
18:40:26 [ErikJ]
... LC124 Questions -- Des ignoreUnknowns impact data mapping?, Is this a tractable problem, Should WSDL define this?
18:40:48 [ErikJ]
18:40:48 [dorchard]
btw, an "isCompatibleWith" attribute in WSDL 2.0 also went down to flaming defeat, see
18:40:55 [cferris]
repeating URI for Henry's Validate Twice:
18:42:46 [plh]
Paul's slides ->
18:43:02 [ErikJ]
[The group is walking through a scenario introduced by waleed, but missed by the scribe]
18:44:16 [ErikJ]
waleed: what about a content model (a, b, c, xs:any) where c is optional? c will be unknown because of UPA?
18:44:52 [ErikJ]
MSM: There is a terminology problem: this is *ambiguous* / non-deterministic, but not unknown
18:45:37 [ErikJ]
dezel: Speaking not as chair, Henry's solution to this problem represents the best of the 80/20 rule.
18:46:09 [ErikJ]
dezel: Hopes we'll give serious consideration of this, although WSDL can do whatever you want
18:47:07 [ErikJ]
holstege: Need clarification [on the "Annotation, Extension, Mandatory" slide in PaulD's slides], which Paul had skipped for time.
18:48:46 [ErikJ]
jmarsh: So, WDSL would say that "a WSDL processor may, must, or should ignore unknown content in msgs where "unknown" is determined by "Henry's algorthm"?
18:48:59 [dorchard]
Hostege, see my note on the options for lc124. It's Annotation for Schema, Extension in WSDL, and possible Mandatory for WSDL.
18:49:17 [ErikJ]
PaulD: I talked to Henry, there were some concerns [but missed by the scribe]
18:49:44 [ErikJ]
MSM: A processor that offers an option for this can be a conformant processor
18:49:57 [dorchard]
I would say "The "ignoreUnknown" property set to "true" indicates that a processor should not fault when processing messages that contain _unexpected items_....."
18:50:11 [dorchard]
and "... The unknown content may be identified by a W3C XML Schema processor. The [validity] property in the Post Schema-Validation Infoset will contain a "notKnown" value if unknown content is found."
18:50:13 [ErikJ]
q2: Isn't the behavior of validators described by the spec? If so, how can you change the validator without changing the spec?
18:51:07 [dorchard]
q2 answer: behaviour is described, you don't change the validator but you layer on top of it to make sure the 2nd validation gets what you want.
18:51:30 [ErikJ]
Noah: What if I wanted a tool that compiles "C", sees a problem, changes the code, and recompiles the code again -- it's the same process
18:52:43 [ErikJ]
Noah is explaining the layered concept in this situation
18:53:08 [ErikJ]
Noah: XML Schema validation is applied to one of the validation passes
18:53:23 [ErikJ]
q2: but having it all in XSD would provide interoperability
18:54:34 [ErikJ]
derekdb: Not having a good way of separating concerns between what to ignore under what context. Partial understanding can turn into "silently ignored"
18:55:21 [ErikJ]
cferris: Most web services don't do validation, many cases it's not a B&W thing whether a message is [XSD] valid,
18:55:37 [ErikJ]
... You don't throw the P.O. away just because of a schema error
18:56:07 [dorchard]
I think web services do validation, but they have compiled code based on the schema which does the validation...
18:56:42 [ErikJ]
... Validation is not necessarily a boolean result, the 2-pass validation may be problematic with security (digital sigs, etc.).
18:56:58 [uyalcina]
+1 to DO. In essence the validation is in the data binding
18:58:25 [ErikJ]
JMarsh: Regarding Noah's presentation and restriction / extension -- Noah: which do you like better?
18:59:16 [ErikJ]
Noah: I was speaking for the WG, there is no definative answer yet -- we are still working the use cases.
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19:01:11 [ErikJ]
JMarsh: The pruning step: requiring validation to process the annotations may be too painful
19:01:37 [dorchard]
If the wording is done right, it doesn't mandate a validation step or 2. It mandates acceptance of unknowns..
19:01:40 [ErikJ]
PaulD: I found myself using UPA because it helps narrow the permutations of possible schemas
19:01:59 [ErikJ]
DanVint: This needs to be down in XSD as well as WSDL -- we need it in schema as well
19:02:45 [ErikJ]
PaulD: [basically agrees]
19:03:27 [pauld]
XML is about communication, so useful to be able to annotate the schema, not just WSDL
19:03:54 [ErikJ]
PaulB: Validate twice operation comes about because the notion that validation in schema is a binary op -- every node in the tree has 6 possible outcomes
19:04:08 [ErikJ]
... tried to validate, did not try, pass, fail, etc.
19:04:38 [ErikJ]
... validate 2x means "if you send extra stuff, it technically des not conform to the schema, but the application may choose to accept it".
19:05:01 [ErikJ]
... I would not want to have a mode in schem that declares the document as valid
19:05:20 [ErikJ]
... other processors can decide if the unknown content is valid
19:06:20 [ErikJ]
MSM: I think this is different -- the behavior of the validate 2x process is different than RDF
19:06:40 [ErikJ]
... I am making the assumption these are all top-level elements
19:06:54 [ErikJ]
... [On the white board]
19:07:59 [ErikJ]
... 2x validation will not accept a document (abcccc) for schema (a, b, c[1-3])
19:09:00 [ErikJ]
... What does WSDL say about the relationship between schemas and the messages a service SHOULD, MUST, MAY accept?
19:09:11 [ErikJ]
JMarsh: It just says "this is the message format"
19:10:26 [ErikJ]
DougP: Extension/restriction -- we have thought a lot about that. Both are useful for different things
19:10:41 [ErikJ]
... Restriction -- how type authors revise existing types
19:11:13 [ErikJ]
... Extension -- Say I author a P.O. type, but implementors want to add new stuff
19:11:26 [ErikJ]
... so, one is for versioning and one is for extension
19:11:40 [ErikJ]
... On this proposal for 2x validation -- it scares me.
19:12:02 [ErikJ]
... we never know where the message is going to be [physically]
19:12:34 [ErikJ]
... It may be that I have a reliable msg system that processes messages not via WSDL (might be MSMQ)
19:12:53 [ErikJ]
PaulD: I was careful to avoid the term intermediary -- I used "observer".
19:13:22 [ErikJ]
DougP: If I strip the soap:header off the top oand process the body later, how to I validate the body?
19:13:41 [ErikJ]
PaulD: The output of validaion is not a binary step -- it's a PSVI
19:13:56 [ErikJ]
DougP: Does my schema processor need to be aware of these rules?
19:14:14 [ErikJ]
PaulD: The app that invokes the schema validator has to be aware of thes tule.
19:14:22 [ErikJ]
s/the tule/these rules/
19:14:36 [ErikJ]
s/thes tule/these rules/
19:15:14 [ErikJ]
DougP: We always want to be able to "beware the evil intermediary"
19:16:41 [ErikJ]
q2: If you add things that are not in the spec, they are chamelion and risk interoperability issues
19:18:25 [ErikJ]
dezel: I would like to ba able to invoke a "contract test"
19:19:46 [ErikJ]
JMarsh: Could we put this in schema?
19:19:54 [ErikJ]
dezel: I don't think we could get there
19:20:29 [dorchard]
WRT DougP's point, it seems somewhat strange to not use WSDL but to use Schema and validate Web Service messages. How does the msmq know what schema to use? Needs a "web service description"..
19:21:10 [cferris]
hmmm... again, I'm not sure I agree
19:21:39 [cferris]
much of the discussion here has been that validation is really an application-level thing...
19:22:27 [holstege]
more like: what to _make_ of incomplete validity or invalidity is an application-level thing
19:22:30 [ErikJ]
Alex: The validate 2x algorithm is a pipeline, so in that sense it is very much at the application level
19:23:11 [dorchard]
no more at the app level than SOAP Handler chains are at the app level..
19:23:19 [cferris]
david e's contract test was: can I process the message? he specifically said, does the message have a 'b' (using MSM's (a, b, c1-3) example where the instance was a, b, c, c, c, c
19:25:07 [plh]
19:25:21 [ErikJ]
DanVint: We just need to have something in schema to help solidify how these processors are expected to act.
19:25:44 [plh]
19:28:20 [ErikJ]
Noah: The reason (good or bad) you choose to skip content is a question you can't answer in the schema spec.
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19:28:59 [ErikJ]
Umit: From a data binding perspective, the WSDL processing is separate from the schema processing issues
19:29:22 [pauld]
we wouldn't have a web if HTML was strictly validated
19:29:47 [dorchard]
There's nothing stopping a Java implementation from doing this in one step when it gets fed the schema + "ignoreUnknowns" property
19:30:12 [ErikJ]
... I don't like to look at this as a two-step process because it won't happen. It's not an application problem-- schema validation is used by data binding independently of the application.
19:30:27 [ErikJ]
... I don't see this as an application issue.
19:31:04 [uyalcina]
JAXB does this already
19:31:41 [noah_Schema_mtg]
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19:32:23 [ErikJ]
dezel: You can't call a vendor and tell them the message they are sending me is invalid because it fails under JAXB.
19:32:39 [ErikJ]
... I can however tell them it fails schema validation -- I use the spec as a hammer
19:34:06 [stevenzenith]
per "we would not have a web if it were strict" - it is one thing to display public data - another to build reliable applications that depend on data contracts
19:34:07 [ErikJ]
Chair: The minutes should show that versioning took up all of the available time.
19:34:37 [holstege]
right, so for some applications, what you make of partial or complete invalidity is to barf
19:35:07 [dorchard]
or partially barf?
19:35:41 [ErikJ]
[The workshop is recessed for lunch until 13:30 Pacific Time]
19:36:44 [douglasp]
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19:37:52 [douglasp]
19:38:26 [douglasp]
David, I saw that you had a question about my statement about durable messages
19:39:16 [douglasp]
I don't think that I explained my scenario clearly enough -- I was just referring to processors that rip the envelope and look at the body solely.
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20:11:39 [cferris]
is to "partially barf" equivalent to "sort of pregnant"?
20:13:48 [ErikJ]
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20:14:00 [pauld]
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20:15:46 [stevenzenith]
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20:46:26 [heidib]
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20:46:38 [pauld]
Topic: Industry Way Forward
20:47:31 [amilows]
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20:47:47 [plh]
20:47:51 [amilows]
From Noah's message:
20:48:11 [pauld]
Scribe: amilows
20:48:46 [amilows]
Tim's message/concern: * want people to understand he thinks sential forms * some that are XML documents conform to schemas and those are sential forms. * there is a lot of value of emphasizing the document view of a world (e.g. a purchase order document is first a document) Please correct if I haven't gotten this right.
20:49:07 [holstege]
20:49:15 [amilows]
20:49:35 [amilows]
Didn't catch that word.
20:49:54 [cferris]
20:52:20 [amilows]
Artciles are on the W3C website and are typically linked from the group page.
20:52:50 [amilows]
Articles, that is...
20:53:37 [cferris]
s/Articles, that is...//
20:53:53 [cferris]
s/Artciles are/Articles are/
20:54:00 [Zakim]
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20:56:19 [amilows]
WAI is for accessibility ...
20:57:15 [amilows]
Might want to discuss that these (slide looking around) are working groups rather than interest groups.
20:57:32 [dorchard]
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20:57:45 [amilows]
I18n working group does not currently develop specifications but they wanted the option.
20:59:02 [amilows]
The wiki is writable by the world... which is an issue.
20:59:27 [amilows]
The i18n group produces articles for users and technical spec writers.
21:00:18 [amilows]
There is a concern about patent policy and the wiki.
21:00:50 [amilows]
That is, outside contributors haven't agreed to the patent policy.
21:01:19 [amilows]
RSS has been working quite well for i18n to reach their users.
21:02:45 [amilows]
Considerations: the resource problem is the biggest issue (e.g. if there is a decision to write an article, someone has to write it).
21:03:49 [amilows]
If more work has to be done to write up Henry's validate twice, then maybe an incubator group would be a good way to do that.
21:04:10 [amilows]
Incubator groups are somewhat like task forces.
21:05:15 [amilows]
Philippe Le Hˇgaret, W3C
21:05:39 [amilows]
That's the end of his talk & discussion.
21:07:27 [amilows]
Next speaker: Ashok Malhotra, Oracle
21:09:15 [douglasp]
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21:09:17 [amilows]
Slide: New features
21:10:10 [amilows]
Typo: Subtypes of date/time with and without timezones
21:10:40 [pauld]
ashok: support entities, schema evolution, remove UPA
21:10:46 [amilows]
Slide: Mapping XML Schema to Objects Classes
21:11:12 [amilows]
Slide: XML Schema Marketing
21:11:26 [amilows]
Need to think about how to sell XML Schema. #1 thing: Marketing!
21:11:27 [amilows]
21:11:42 [pauld]
you can sell anything in america
21:12:21 [amilows]
Can you take a class? Yes, in the information systems schools and not the CS departments.
21:13:11 [amilows]
Typo: Interactive learning tools? Instead of 'interaction leaning tools' ?
21:13:52 [amilows]
Need more books (e.g. more than one)
21:14:03 [amilows]
A better primer...
21:14:29 [amilows]
Some published best practices aren't necessarily "best practices".
21:14:42 [amilows]
Need better testing and certification.
21:15:14 [amilows]
Questions: Who ought to do this?
21:15:24 [amilows]
...and need resources.
21:15:46 [cferris]
is this the "coach" to which Ashok was referring? it is Regex Coach and written in Lisp
21:15:48 [cferris]
21:15:50 [amilows]
The W3C is not experienced in certification.
21:15:57 [amilows]
NIST has experience doing that.
21:16:38 [amilows]
Question: What does SQL do?
21:16:45 [amilows]
Is there some kind of SQL certification?
21:16:57 [amilows]
NIST had some kind of SQL certification.
21:17:09 [amilows]
...but that was in the 80's
21:17:23 [pauld]
thought all ISO STANDARDS had conformance suites
21:17:23 [amilows]
There was a certification program with fairly good coverage.
21:17:33 [amilows]
But that's a very expensive thing to run.
21:17:38 [amilows]
And it is hard to do.
21:17:47 [amilows]
Right now, there is no SQL certification program.
21:18:27 [amilows]
One thing missing on the slides: library of reusable components (e.g. a type library).
21:19:07 [amilows]
Registries aren't popular at the W3C.
21:19:16 [amilows]
Registry implies a unique thing...
21:19:20 [amilows] maybe not...
21:19:26 [amilows]
Repository is where you put it.
21:19:32 [amilows]
Registry has a unique identification.
21:20:11 [amilows]
Producing schemas is not the same as testing and processor that uses schemas.
21:20:50 [amilows]
Noah: A lot of care has to be done to put into describing what the kinds of software is considered a process and what it does.
21:20:54 [cferris]
s/Producing schemas/Noah: Producing schemas/
21:21:07 [amilows]
There is a layer of work that needs to be done...
21:21:48 [amilows]
Type libraries may be an ideal thing for an incubator group.
21:22:01 [amilows]
Next speaker: Soumitra Sengupta, Microsoft
21:22:24 [dorchard]
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21:25:15 [amilows]
He is entrusted with the team that builds the core components.
21:25:27 [amilows]
Slide: Office Customer Scenarios
21:25:52 [amilows]
Co-occurrence constraints are important that they'd like to see it layered on schema.
21:26:01 [amilows]
Slide: Office Experience
21:26:16 [amilows]
The format for word will be XML going forward.
21:26:50 [amilows]
Slide: Office Experience - Excel
21:27:11 [amilows]
When confused on simple types, it defaults to string.
21:27:17 [mnot]
...said that Visio is the only office format that won't move from binary files to XML.
21:27:30 [amilows]
In office 2003, there are some restrictions and may not be there in the next version.
21:27:39 [amilows]
Slide: Office Experience - InfoPath
21:28:31 [amilows]
has something similar to co-occurrence constraints
21:28:41 [amilows]
Slide: We feel the pain
21:30:07 [amilows]
There has been a tremendous amount of work on schema conformance in the next System.XML and MSXML 6.
21:31:08 [amilows]
Slide: Key pain points
21:31:25 [amilows]
A better formal specification would be helpful.
21:32:23 [amilows]
XML to object/XML to Relational is not an easy problem and will not get fixed easily.
21:32:40 [amilows]
Trying to change the schema to solve this problem is not the right thing.
21:33:36 [amilows]
Slide: There is progress as well
21:34:17 [pauld]
somitra: 300,000+ developers using xsd
21:34:38 [pauld]
21:35:11 [amilows]
At XML 2005 they will present a full study of what they've found.
21:35:49 [amilows]
There is tremendous value in XML Schema. Don't just change it...
21:36:13 [amilows]
Office support the full XSD spec will increase its use.
21:36:59 [amilows]
The file saved in the next version will be a zipped XML document.
21:37:34 [amilows]
XSD is providing real value in-spite of the pain.
21:37:59 [amilows]
Slide: We can and should do more.
21:38:21 [amilows]
XSD 1.0 should still be the basic foundation of exchange.
21:38:33 [amilows]
Will collaborate with all vendors for interoperability.
21:39:42 [amilows]
Strongly believe data binding should be out-of-scope for the W3C.
21:40:23 [amilows]
Profiling is not a bad thing. Microsoft had a different position at one point.
21:41:04 [amilows]
Noah: When doug talked about profiles, profiles are a good thing to optimize around... you appear to be going further.
21:41:20 [amilows]
Profiles are a good thing but middleware should support the whole thing.
21:41:39 [amilows]
Investing a lot in best practices...
21:42:09 [amilows]
...should include actual schemas that are working.
21:42:31 [amilows]
Questions, comments:
21:42:41 [amilows]
"Perfection is enemy of good"
21:43:14 [amilows]
Question: Lots of people say the spec is complex, but no one mentions the primer. Are people reading the primer?
21:43:32 [amilows]
Everyone reads the primer and then the spec...
21:44:28 [amilows]
People have said "just say no to WSDL2"... just look at the spec... but it is hard to make those kind of specs easier.
21:44:52 [amilows]
The primer is great for your first introduction... then you need to find your local guru to understand further.
21:45:53 [amilows]
Michael: What we need is "readers" for XML Schema.
21:46:43 [amilows]
Michael: Examples need to be relevant to the reader.
21:47:22 [amilows]
...this is not a new problem... every language has this challenge at the beginning...
21:48:15 [amilows]
Paul: My memory, we had part 1 and part 2 and one member said "I'm going to write a primer" and then it was published as part 0. So, if someone thinks we need a reader, then write one.
21:50:28 [amilows]
J. Marsh: Now every working group should have a primer material and that's not core to the WG and so the work stretches out for years. Constrain the WG, try not to do primers, and then have outreach groups to do these things. At this point, you've done a primer, 5 years of experts, there's a market for that material,... but the schema group now offers producing the errata and getting all the nits worked out.
21:50:50 [amilows]
J. Marsh: If interoperability is a priority, test suites and errata would be very valuable.
21:51:42 [dorchard]
I will point out that in WSDL 2.0 people have not generally wanted to do work on the primer, but people have now started using the primer examples for making their points and it's changed WG members opinion on issues.
21:51:47 [amilows]
Noah: Clarification work is need for both users and spec readers. Have had reports from people who said that it was very painful but that it does answer the questions. One of the traps we could run into is that "doing x or y that is different" could run into problems.
21:52:00 [amilows]
Noah: This spec two many passes and this is the best we came up with...
21:52:45 [amilows]
Noah: One of the problems is that we'll change something that was correct event if hard to find when we change the spec for clarity.
21:53:11 [amilows]
Noah: My view, at this point, the best is to do selective clarification. Fixes to the spec where necessary.
21:53:39 [amilows]
Noah: In selected more major areas, clarification of certain areas (e.g. imports and includes).
21:54:39 [amilows]
Point: the original specification doesn't go away...
21:55:34 [amilows]
The risk in clarifying the spec is that to change one thing you might have to change a lot of the spec.
21:56:48 [amilows]
Chris: Talking about what the WG can do... but... when go to spec and chase down the rules... and you become enlightened but there is no record of that so others can benefit.
21:56:58 [amilows]
Noah: The FAQ started that way...
21:57:19 [amilows]
Chris: If it was easier for the public to contribute that might provide a lot of value.
21:57:47 [amilows]
Soumitra Sengupta: What we do is write the tests...
21:58:21 [amilows]
Noah: People who know how to read the spec, then you function... we should publish that.
21:58:56 [amilows]
MichaeL: If you want to know if an instance is value, you start in section 5.2. Not everyone knows that.
21:59:14 [ht]
22:00:30 [amilows]
(?): go through and actually apply the rules... to figure that out, the rules aren't cross-related. It is clumsy... maybe if you start from the right spot knowing what you are looking for... you have to watch for these edge cases isn't actually called out... ...and follow a lot of dead ends.
22:00:49 [amilows]
Noah: want an annotated XSV...
22:00:56 [stevenzenith]
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22:01:13 [amilows]
(?): tool vendors encounter issues in different order...
22:01:25 [JonC]
? = derek
22:02:34 [amilows]
Michael: if we could safely refactor the document, we'd do it in a flash. There are different opinions on what safe, refactoring, etc. means...
22:02:37 [pauld]
22:03:03 [pauld]
s/? = derek//
22:03:16 [amilows]
J. Marsh: What's done is done. Not clear if the pain is increasing or dropping.
22:03:38 [amilows]
What about new implementers...
22:03:39 [amilows]
22:03:47 [amilows]
Do they need to spend 5 years too?
22:04:12 [cferris]
s/What about new/pauld: What about new/
22:04:42 [amilows]
Noah: Mystified that there aren't more books.
22:06:17 [amilows]
David: wanted to respond to "chickening out"... don't feel that we're chickening out. Feeling that since we've failed to write a clear thing, we may not be the right person to write this. There are two important reader groups: Einstein's and elvis's...
22:06:26 [amilows]
David: Need more material for Elvis...
22:06:37 [amilows]
But elvis is dead...
22:06:43 [ht]
HST would like to get a sense from this group if we added one more thing to structures beyond the status quo, namely weakened wildcards (we already have subsumption for particle restriction agreed), nothing more to datatypes (i.e. the impending last-call draft), and NOTHING MORE, and declared victory on 1.1, with a promise to focus subsequent effort on 1) Layering co-constraints on top, separately; 2) Best practices for versioning, working with what we've got; 3) lot
22:06:50 [cferris]
elvis has left the room
22:06:50 [dorchard]
A few years ago people would use XFront's schema design guides regularly..
22:07:26 [amilows]
session ended...
22:07:36 [ht]
It's HST's bedtime, hopes someone will feed in his comment at the appropriate time
22:08:04 [ht]
MSM/Noah/Mary -- do you understand what I'm suggesting?
22:09:40 [ht]
If you see MSM/Noah/Mary/Dezell about, ask them to come back on this channel ASAP if my point is not clear
22:09:46 [ht]
22:14:31 [ht]
HST feels that we could easily use at least 50% of the (hopefully expanded) WG's time for a year putting out Best Practice Versioning Notes just on how to make the best use of our existing design, and if we did that for a year or 18 months then we might have enough concrete experience to look at XML Schema V for Versioning
22:14:59 [ht]
And I hear a lot people asking for those Notes here today
22:35:26 [ErikJ]
Are the Best Practices Notes public?
22:36:27 [scribe]
Paul suggests 15 minutes for each 3 topics and 45 mins for wrap up
22:36:51 [scribe]
Three topics are validation, profiles and UPA
22:37:46 [scribe]
Topic: Validation/Code Generation
22:38:02 [scribe]
Marsh: This is related to LC124 in WSDL.
22:38:50 [RRSAgent]
I have made the request to generate plh
22:39:46 [scribe]
Paul: Is the code binding a requirement?
22:41:32 [scribe]
MSM: Presents DO's example (last name, first name, any element can appear in between or after)
22:42:29 [scribe]
Noah: Code binding is a placeholder for broken code binding. (No mixed content, no choice).
22:43:24 [scribe]
Dana: Sympathetic to code binding, but it is not the only use case (X Query)
22:44:06 [scribe]
DO: First name, last name, and a wildcard that leaves the possibility of extension a middle name.
22:45:26 [scribe]
... There are actually two examples. Middle name (when it occur in the middle) is separate.
22:46:29 [scribe]
DougP: To make changes to schema to support data binding is leaky. This leads to the profile discussion. However, w3c making a change for writing generators is not good idea.
22:46:47 [kohsuke]
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22:47:48 [scribe]
Discussion about what UPA is...
22:47:58 [scribe]
Ashok: Prevents backtracking.
22:48:31 [kohsuke]
RELAX NG proved once and for all that you can do without back-tracking even if you don't have UPA
22:49:04 [scribe]
PaulD: What is the difference in typing and binding?
22:49:42 [scribe]
Noah: Binding is where you will put it in a Java bean, for example.
22:50:36 [scribe]
MSM: With UPA you can use a simpler contruction and build deterministicly. The automata is deterministic by UPA.
22:51:25 [Marsh]
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22:51:52 [kohsuke]
I mentioned that you might save a little in constructing a state machine but you'll pay a big cost of checking UPA
22:51:54 [scribe]
Paul: The other thing UPA does is when there are appinfos attached to elements, if I get content model that violates UPA which one do I use? It prevents this case.
22:53:33 [plh]
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22:53:33 [scribe]
Derek: We have tools that depend on appinfo, annotations. I will be uncomfortable in loosening the restriction.
22:54:12 [dezell]
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22:54:39 [scribe]
Paul: How does this interact with databinding? JAXB uses Appinfo. In an ambiguous content model, it willbe problematic. I like determinism.
22:54:58 [scribe]
Topic: Profile
22:55:17 [scribe]
Paul: Are profiles useful or harmful?
22:56:42 [scribe]
DougP: In perfect world we will not have a profile. Programming model will be aligned with schema, but it is not the case. Pressure from customers dictate what we do.
22:57:17 [scribe]
... We have used the lessons learned from SOAP builders and adopted in WS-I basic profile.
22:57:46 [dorchard]
It's not nearly as rosy as that because some vendors have profiled the profile.
22:58:37 [scribe]
... No attributes, use element, xsd primitives sequence,... can become a profile.
22:59:46 [scribe]
... There are two different scenerios: code first vs. schema first.
23:01:01 [scribe]
CF: If WS-I did not preclude the stuff outside the profile, then it will be possible to guarantee a reasonable programming model.
23:01:37 [scribe]
... We could say this and it will not preclude others to use other features.
23:02:21 [scribe]
DougP: The key is that tools should not fail outside the boundary. The vendors should support all the schemas.
23:03:44 [scribe]
CF: It is not an interop problem, it is a convenience problem.
23:04:00 [stevenzenith]
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23:04:31 [scribe]
David: I keep IIOP. Does the profile solve a problem or introduce a set of conventions?
23:04:54 [cferris]
s/keep IIOP/keep hearing IIOP/
23:05:04 [scribe]
Paul: There is a strong market for tools that support a particular feature set.
23:05:27 [Zakim]
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23:05:53 [scribe]
... If you stay within a feature set, you will get a good programming experience.
23:06:11 [cferris]
there is never a guarantee of interoperability
23:06:26 [scribe]
Ashok: Another way is to say always use element form qualified, etc. These are user guidance.
23:07:45 [scribe]
Jon: If the profiles can not be verified by tools, they are not that useful.
23:07:49 [scribe]
umit: +1
23:08:13 [scribe]
Noah: Optimize for the profile, but support everything...
23:09:53 [cferris]
+1 to what noah said
23:11:36 [scribe]
Mark: There are languages PHP, Python...
23:12:52 [scribe]
Noah: A simple subset of the schema will be easy to write a parser for.
23:14:37 [scribe]
Paul: Worried about profiling. We have profiles for HL7.
23:15:12 [scribe]
DougP: When we engage with customers, users do not want DOM.
23:15:16 [scribe]
umit: +1
23:15:38 [mnot]
23:16:05 [scribe]
Paul: Why can not the tool vendors do more?
23:17:11 [scribe]
Marsh: Another thing a profile does to encourage vendors to extend the patterns of use.
23:17:54 [cferris]
soumitra mentioned two experimental efforts at incorporating XML into Java and C#, namely XJ ( and Cw (
23:17:57 [scribe]
DougP: We like to represent graphs, but noone can understand semantics.
23:18:32 [cferris]
s/soumitra mentioned /soumitra mentioned in his talk/
23:18:47 [scribe]
... As long as we can use a different mapping but preserve our semantics, we are ok.
23:19:58 [scribe]
Paul: how many think that a schema profile is a good idea?
23:20:04 [scribe]
Answer: 16
23:20:25 [mnot]
30 in the room (not counting chairs and W3C)
23:22:09 [scribe]
Discussion on what the next question should be...
23:22:19 [scribe]
23:23:20 [scribe]
Noah: Profile we are discussing is a specific purpose: data binding. There are other uses of profiles.
23:23:31 [scribe]
s/Profile/The profile/
23:23:45 [scribe]
s/is a/is for a/
23:25:12 [scribe]
PaulD: If a profile is done, should it be done at the w3c?
23:25:48 [scribe]
Steve?: The question is whether the mechanism is defined by the w3c and the profile is defined elsewhere...
23:33:58 [dezell]
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23:34:11 [scribe]
Umit: There are two questions. Explicit support in the language for the definition of a profile vs definition of a contrained set of XML Schema features which is helpful for data binding
23:35:08 [scribe]
DF: Layers of compatibility was not a good experience for XQuery. Everyone will implement everything anyway.
23:35:46 [stevenzenith]
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23:36:09 [scribe]
??: Profile will help getting the spec together. For example, profiles that define extensions will help reduce the complexity of the spec and understanding of the requirements.
23:36:32 [scribe]
.. There needs to be one source of profiles, preferable w3c.
23:36:42 [scribe]
23:37:24 [scribe]
David: A process question: We are running out of time and we can not resolve what the profile should be. We need to focus on the specific question.
23:37:36 [scribe]
... Is the w3c the right place to do this?
23:38:09 [scribe]
MSMQ: Time for us to move to the summary.
23:39:26 [cferris]
my view is that if the web services activity were the venue for a profile that defined the sweet spot of xsd 1.0 that made for a pleasant user experience, I could support that, but I also think that ws-i may be a better venue since we already are set up to develop profiles
23:41:55 [cferris]
wiki good
23:42:42 [scribe]
umit: +1 wiki
23:45:04 [scribe]
Noah: It has been an repeated experience in w3c we do better with concrete proposals. That is hard to ask from the users. Notheless, the same approach applies.
23:45:47 [scribe]
... s/notheless/nonetheless/
23:48:25 [scribe]
HenryT asks: weakened wildcards, simplified definition of restrictionm datatypes in current draft: can we call victory ?
23:49:12 [scribe]
23:50:26 [scribe]
... would like to focus on (1) layered co-constraints (2) best practices for versioning.
23:50:41 [dorchard]
Worried that this doesn't set Schema up for what it needs going forward wrt versioning. weakened wildcards is at best a partial solution. Mutliple namespace documents are very common.
23:50:53 [scribe]
... This is a proposed program for XML Schema 1.1
23:51:38 [scribe]
Derek: How does it work with existing processors?
23:52:46 [scribe]
David: our intention has been not to cause unnecessary pain.
23:53:45 [dorchard]
Can fix versioning by doing additions that are optional and thus compatible.
23:55:39 [scribe]
Discussion on what w3c should do...
23:56:05 [scribe]
... should there be Schema 1.1 or not?
23:56:45 [scribe]
Noah: What does it mean? What should the wg should do then if 1.1 was dropped.
23:57:21 [scribe]
MSMQ: Effect of dropping 1.1 would mean that maintanence of the test suite and errata as well as the promotion material preparation.
23:57:38 [scribe]
... will be the focus of the wg.