- From: Thomas Baker <tbaker@tbaker.de>
- Date: Fri, 31 Mar 2006 10:14:20 +0200
- To: SW Best Practices <public-swbp-wg@w3.org>
SWBPD VM 2006-03-31 telecon agenda Note that as of 2006-03-26, Central Europe is on "Summer Time"! Friday, 13:00 UTC -- 14:00 London -- 15:00 Berlin http://www.w3.org/Guide/1998/08/teleconference-calendar#D20060331 Zakim: +1-617-761-6200 Conference code 8683# ('VMTF') irc://irc.w3.org:6665/vmtf ---------------------------------------------------------------------- AGENDA As agreed on 2006-03-17, this last telecon of the VM Task Force under the current SW BPD charter will focus on taking stock of outstanding issues. At a minimum, we should discuss the issues listed below under "Remaining Issues to Discuss". Time-permitting, we should look at issues from the "VM Task Force Web page", also listed below. The final, edited version of this document can serve as a point of departure for discussion in the context of a new SW working group. ---------------------------------------------------------------------- LINKS Reports of recent telecons [1] 2006-02-07: http://lists.w3.org/Archives/Public/public-swbp-wg/2006Feb/0059.html [2] 2006-02-14: http://lists.w3.org/Archives/Public/public-swbp-wg/2006Feb/0115.html [3] 2006-03-17: http://lists.w3.org/Archives/Public/public-swbp-wg/2006Mar/0051.html Current draft, under discussion [4] http://www.w3.org/2001/sw/BestPractices/VM/http-examples/2006-01-18/ David Booth's re-review comments of Feb 15 [5] http://lists.w3.org/Archives/Public/public-swbp-wg/2006Feb/0109.html Current VM Task Force Web page [6] http://www.w3.org/2001/sw/BestPractices/VM/ Older, abandoned draft, not to lose sight of... [7] http://esw.w3.org/topic/VocabManagementNote ---------------------------------------------------------------------- OUTSTANDING ACTIONS ACTION (ongoing): Ralph to test recipes with W3C configuration. ACTION 2006-03-17 Ralph: Contact Matthew Ellison about our interest in having STC participate in VM writing. AGREED 2006-03-17 to focus the last telecon on clarifying the list of issues to be carried forward into future chartered working groups. ---------------------------------------------------------------------- REMAINING ISSUES TO DISCUSS 1. David Booth's review, Point 7: "Interpretation of fragment identifiers" Recipe 3. Hash Configuration, Extended: I don't think the comment from my previous review was addressed: "Because the interpretation of a fragment identifier in the presence of 303 redirects is unclear as far as I know, I think this recipe should note that the browser may or may not apply the fragment identifier to the secondary URI." 2. Hash namespace URIs On 2006-02-14, Ralph pointed out [*] that the Cookbook shows vocabulary http://isegserv.itd.rl.ac.uk/VM/http-examples/example1 defining classes http://isegserv.itd.rl.ac.uk/VM/http-examples/example1#ClassA http://isegserv.itd.rl.ac.uk/VM/http-examples/example1#ClassB consistently omitting the trailing '#' from the vocabulary name. [*] http://lists.w3.org/Archives/Public/public-swbp-wg/2006Feb/thread.html#msg105 "I claim this is a fundamental mistake and would argue it on the basis of both semantics and what the RDF core specifications state. The semantic point is that [a] should be the name of the vocabulary while [b] is the name of a document that might (should) describe that vocabulary." [a] http://isegserv.itd.rl.ac.uk/VM/http-examples/example1# [b] http://isegserv.itd.rl.ac.uk/VM/http-examples/example1 3. Longer-term issue: alignment of content-negotiation ideas in the cookbook with TAG: -- http://www.w3.org/2001/tag/issues.html#namespaceDocument-8 -- Associating Resources with Namespaces Draft TAG Finding 13 December 2005 http://www.w3.org/2001/tag/doc/nsDocuments-2005-12-13/ ---------------------------------------------------------------------- VM TASK FORCE WEB PAGE - as of November 2005 Short-term objectives -- To define (in a Note <http://www.w3.org/2003/glossary/keyword/Process.rdf/?keywords=Note> or Editor's Draft) a set of good-practice "recipes" for configuring an Apache server for content negotiation such that: o If a person tries to dereference the URI of a class or property (i.e. via a Web browser), they end up at the relevant bit of human-readable documentation. o If a machine tries to dereference the URI of a class or property, they end up with a serialisation of a set of RDF statements describing that class or property, with a provenance that allows differentiation of different 'versions' of an RDF schema/ontology. o The dereferencing solution complies with TAG resolution on httpRange-14. -- To wrap those recipes in enough context to make them usable by vocabulary maintainers to provide documentation and schemas for their vocabularies. Long-term issues -- URIs based on PURL.ORG. DC, RSS, and vocab.org use URIs based on purl.org, which currently responds to GET requests with 302 (Temporarily Moved). The TAG decision on httpRange-14 <http://lists.w3.org/Archives/Public/www-tag/2005Jun/0039.html> requires 303 (Redirect). This was discussed in a mailing list thread <http://lists.w3.org/Archives/Public/public-swbp-wg/2005Aug/0037.html>. In July, Dan asked TAG <http://lists.w3.org/Archives/Public/public-swbp-wg/2005Jul/0056.html> whether a 302 response on a purl.org URI would be acceptable. As of November, Alistair has included purl.org scenarios in the draft cookbook <http://www.w3.org/2001/sw/BestPractices/VM/http-examples/2005-11-18/>. -- Awareness of multiple representations. If content negotiation is handled in the background and alternative representations of a vocabulary in RDF or HTML are served up to a user seemingly automatically -- on the basis of Apache configurations -- how would an interested user know which other representations were available <http://www.w3.org/2005/10/28-vmtf-minutes.html>? Should there be some way for a user to learn about other representations (e.g., via cross-references or an overview page)? --Notion of a "Definitive RDF description". Peter Patel-Schneider has questioned the focus on one "definitive RDF description" for each RDFS/OWL class, property, or individual -- as opposed to an RDFS description, an OWL description, or multiple "definitive" descriptions <http://lists.w3.org/Archives/Public/public-swbp-wg/2005Nov/0075.html>. -- Provenance and URIs. Provenance is supported by using the final URI from the chain of redirects as the name of the graph; different URIs represent different versions of a vocabulary. Tom has noted that, in practice, "date-stamped" URIs are often used <http://lists.w3.org/Archives/Public/public-swbp-wg/2005Nov/0078.html> and suggests we explicitly acknowledge both that URI strings are in theory opaque and unparsable and that there are de-facto social conventions for using date stamps or version numbers. -- rdfs:isDefinedBy. Clarifying the dereferencing options provides an opportunity to clarify good practice for the use of rdfs:isDefinedBy <http://www.w3.org/2000/01/rdf-schema#isDefinedBy>. Instead of relying on URI string manipulation in an attempt to heuristically locate a namespace, namespaces should be declared with rdfs:isDefinedBy. -- Change management for RDFS/OWL ontologies. There was discussion on whether this should more properly be called "change management" or even "version documentation". Current DCMI practice <ftp://ftp.cenorm.be/public/ws-mmi-dc/mmidc148.pdf> has been described. The emerging consensus is that it is best to version the description of a property (i.e., the RDF statements about it), not the property itself. I.e. each 'version' is a named graph; provenance information can then be used to distinguish between different descriptions of a property. Alistair notes that the issues of versioning and change management are coming to the fore in the OWL community. o Part 1. Naming <http://isegserv.itd.rl.ac.uk/cvs-public/~checkout~/swbp/vm/change-management/part1.html> o Part 2. Metadata <http://isegserv.itd.rl.ac.uk/cvs-public/~checkout~/swbp/vm/change-management/part2.html> -- Principles of Good Practice (see Wiki draft <http://esw.w3.org/topic/VocabManagementNote>). o Identify Terms with URIs. o Articulate and publish maintenance policies for the Terms and their URIs. o Identify the historical version of a Vocabulary or its Terms. o Provide natural-language documentation about the Terms. o Declare the Terms using a formal, machine-processable schema language. See also -- 2005-11-22, Vocabulary Management Task Force progress report <http://lists.w3.org/Archives/Public/public-swbp-wg/2005Nov/0122.html>. Dependencies -- SWBP Thesaurus Task Force (THES) <http://www.w3.org/2004/03/thes-tf/mission> -- TAG decision on httpRange-14 <http://lists.w3.org/Archives/Public/www-tag/2005Jun/0039.html> -- SWBP response to TAG decision on httpRange-14 <http://lists.w3.org/Archives/Public/public-swbp-wg/2005Sep/0010.html> ---------------------------------------------------------------------- ISSUES ALREADY DISCUSSED - David Booth's re-review [5] -- Point 1: As decided on the Feb 20 BPD telecon, Tom added text about URIs coined using the http://thing-described-by.org 303-redirect service [a,b,c]. [a] http://lists.w3.org/Archives/Public/public-swbp-wg/2006Mar/0027.html [b] http://www.w3.org/2001/sw/BestPractices/VM/http-examples/2006-01-18/#other [c] http://www.w3.org/2001/sw/BestPractices/VM/http-examples/2006-01-18/#redirect David's point: Using a 303-redirect service, while quite new as an approach, would theoretically be simpler to implement than the recipe in the Cookbook claimed to be "the simplest". Suggests adding an editor's note. Tom took this as an action on the Feb 20 telecon and followed up by adding some text [5], which David Booth approved. Alistair is not convinced that using 303 redirects is actually simpler; he hasn't written up his thoughts yet. A 303 redirect service is not new; that's exactly what purl.org is. He is also not sure that 303 is simple for slash namespaces -- see recipe 2a. You still need a rule that catches multiple targets. It is similar to the partial redirect problem in purl.org. If t-d-b could be configured then lots would be easier, but without that t-d-b is functionally equivalent to purl.org partial redirects; and t-d-b relies on the persistence of 2 URIs whereas purl.org only relies on the persistence of one (purl.org) URI. This option has not been fully explored, so we should look more closely at the supposed simplicity of the 303-redirect solution and consider whether TDB is really the best alternative. -- Point 2: "Title of Section 3" "Big-picture overview of server configuration steps" David suggests some text to add [2]. -- Point 3: "Title of Section 3" Currently called "Some considerations when choosing a URI namespace". David suggests: "Choosing a namespace URI: hash versus slash". Alistair opposed to renaming the section to include "hash vs slash" text (Ralph agrees): we want to take out all references to past quagmires and think about readers coming to document for first time - they want clean, concise look at problem. -- Point 4: "Wording in Section 3" David suggests a change of wording in one sentence in line the new title (see 3 above). Ditto for wording of section three: better not to bring up old arguments about hash versus slash. ACTION Ralph: Contact Matthew Ellison about our interest in having STC participate in VM writing. Matthew Ellison <matthew.ellison@email.com>: represents Society for Technical Communication (STC), a W3C that is providing volunteer resources for a range of W3C writing and eLearning development activities. These activities include editing specifications, developing tutorials for W3C tools and technologies, and writing summaries on emerging W3C technologies and specifications. -- "More-helpful comment line in the recipes" Suggests a few more words. -- Point 5: "Pros and cons of hash versus slash URIs". David requests "more-explicit guidance on hash versus slash URIs" -- additional discussion of Pros and Cons. Alistair: Text of David's suggested editor's note isn't quite correct. Also, prefer to keep this document at the need-to-know level. If some pros and cons are to go into this document, they ought to be as simple as possible and gently worded. Would prefer if all document on making choices were made externally to this document (i.e., in another document), then just cite it. Ralph: Hard to keep this document both simple, and detailed enough for people curious to look under the hood. Feels right to have an entirely separate discussion document. -- Point 8: Numbering of sections is requested. -- Point 9: s/URI namespace/namespace URI/ throughout ---------------------------------------------------------------------- ISSUES ALREADY DISCUSSED - Structure of Cookbook document as a whole -- Tom proposed putting the requirements at the top, etc: http://lists.w3.org/Archives/Public/public-swbp-wg/2006Mar/0048.html Tom: As currently written, there is nothing in the introductory sections that simply says: "This document shows you how to publish both machine- and human-readable versions of a vocabulary." The requirements need to be expressed up-front in some form, if only in a sentence or two. Alistair: Deliberately put the "Requirements" section at the back of the document because it is not need-to-know for the reader -- it's really there for the WG. I'd rather the Requirements were not there at all. Ralph: Putting in alot of editorial notes, then stripping them out in the final product is not a bad process. Alistair: the "Apache Configuration" section is another thing that could be moved to an Appendix. The important section is Choosing a recipe -- we want to get the reader there as quickly as possible. Introduction, then Choosing a Recipe, directly. Tom, Ralph, Alistair agree: Need to provide the motivation for this specification in the introduction. Alot of the detail could be pushed to appendix: URI namespaces; the second Apache configuration. We need to decide what to expect of readers - will help us decide what to keep in. If we physically move stuff down, then flavor becomes "we don't think you want to see the details..."... That tone is a dramatic change from what we have now. Diagrams helped us, but may not be necessary for the intended users. Simple visual images could perhaps convey these choices with less detail. -- Recipe 6 is still a placeholder [*]. [*] http://www.w3.org/TR/2006/WD-swbp-vocab-pub-20060314/#recipe6 -- Dr. Thomas Baker baker@sub.uni-goettingen.de SUB - Goettingen State +49-551-39-3883 and University Library +49-30-8109-9027 Papendiek 14, 37073 Göttingen
Received on Friday, 31 March 2006 08:14:21 UTC