[VM] Telecon Tuesday (today) 15:00 UTC

SWBPD VM 2006-01-31 telecon agenda

Tuesday, 15:00 UTC (16:00 Berlin)
Zakim: +1-617-761-6200
Conference code 8683# ('VMTF')

Recent telecons
-- 2006-01-24: http://lists.w3.org/Archives/Public/public-swbp-wg/2006Jan/0125.html

Next telecons (weekly)
-- 2005-02-07 Tue 1500 UTC http://www.w3.org/Guide/1998/08/teleconference-calendar#D20060207
-- 2005-02-14 Tue 1500 UTC http://www.w3.org/Guide/1998/08/teleconference-calendar#D20060214


-- New version is:

   --- $Id: Overview.html,v 1.6 2006/01/27 04:23:11 ajm65 Exp $ ---

   2006-01-27: editorial control passed to Tom B.

-- Title is now 'Best Practice Recipes for Publishing RDFS
   and OWL Vocabularies/Ontologies'. Alistair argued for having
   the words 'OWL' and 'ontologies' in the title somehow,
   to acknowledge the community and improve search hits using
   those words; he was, however, tempted by the tantalisingly
   snappy 'Best Practice Recipes for Publishing RDF'.

-- Alistair cannot attend the call today.  He is in agreement
   to advance to Working Draft pending TF consensus on the
   issue raised at [1].  The problem is that the content
   types "text/xml" and "application/xml", which are used
   in the rewrite rules, are ambiguous inasmuch they are in
   practice used to label either HTML content or RDF content.
   Alistair suggests removing both of the content types as
   conditions from the rewrite rules.  Does the TF agree?

   [1] http://lists.w3.org/Archives/Public/public-swbp-wg/2006Jan/0163.html

-- It has been suggested that the 'testing' sections contain
   a script of some sort for automatically running the
   tests. For testing purposes, Alistair tried unsuccessfully
   to get wget to change the default Accept headers.  Does anyone
   know of an alternative command line HTTP client for use in a 
   shell script?

-- Alistair has implemented and tested all the new
   configurations, using the tests given in the document.
   See http://lists.w3.org/Archives/Public/public-swbp-wg/2006Jan/0154.html

-- We are up-to-date on all actions except:

   ACTION: Ralph to test recipes with W3C configuration.


1.  Editor's Draft 
    "Best Practice Recipes for Publishing RDFS and OWL Vocabularies/Ontologies"

    1.1. 2006-01-24 - Resolved: To ask the SWBP Working Group
         at its Feb 6 telecon to approve publication of a Working Draft.

    1.2. New version in preparation:
         Alistair working on this for now, making structural changes.
         Should not be edited in-place by others until Alistair explicitly
         passes the token.

    1.3. Cookbook name: "Best Practice Recipes for Serving
         RDFS and OWL Vocabularies" was decided on Jan
         17.  Since then, further discussion of details.
         A weak preference for "publishing" (instead of
         "serving"); just "RDF vocabularies"; and "short
         is better" - but Alistair has some latitude here
         to decide.  Alistair would like the title to mention

2.  Default response - "the IE6 problem"

    RDF as the default response was discussed in December:

    Alistair has since found that conditional redirects work differently
    with Mozilla and IE6 because the two browsers send different
    Accept headers with an HTTP GET request.  Hence if we want 
    URIs to be clickable in IE, either we
     (a) leave the recipes as they are and ask IE to send more headers, or
     (b) change the recipes around and ask RDF toolkits to send more 

    Changing the default to HTML could break existing
    SW apps, which traditionally behave as if RDF were the default.
    And we note that servers are not required to respect Accept
    headers.  We therefore think that the Cookbook's stance should
    be to support either HTML or RDF as the default.

    Alistair thinks this might be done most elegantly by including
    lines supporting HTML as the default in each of the recipes --
    but commented out.  If cut and paste exactly "as is", each
    recipe would default to RDF.  The accompanying text would
    however explain how to uncomment lines to set the default
    to HTML.  Commenting and uncommenting the lines in question
    would "flip the switch" between a default of HTML and a default
    of RDF.  Additional notes in the Appendix could suggest ways
    to use User Agent to work around the lack of Accept headers
    in picking an appropriate response.

    ACTION - DONE: Alistair added commented/uncommented
    lines to recipes to support either HTML or RDF as default.
    Ralph argued for RDF as default response where content
    negotiation is configured, because of dependency of current
    Semantic Web applications.  We found a way around the
    problem in IE6 that allows URIs to be clickable even with
    RDF as the default. Ralph argued for this 'workaround'
    to go into an appendix. Alistair tried doing this, but made
    a decision to incorporate it into the recipes, because
    that way the vast majority of people will be able to just
    copy and paste from one location to another. It didn't
    make sense to recommend RDF as the default, and then
    direct everyone who wanted IE6 clickability (i.e. almost
    everyone) to an appendix that says how each recipe needs
    to be modified. See the new section 'content negotiation'
    for an explanation.

3.  Responses to reviews

    On Jan 10, we decided that in January we would discuss
    reviewer comments and formulate responses to reviewers
    on the list.

    3.1. David Booth review
         -- Global suggestions
            G1. To discuss trade-offs between hash and slash URIs
                Response: Ralph has addressed this with added text in the
                introduction. David has not yet indicated whether he is 

            G2. To avoid purl.org recipes, which violate TAG resolution 
                with 302 redirect code.

                Problem with purl.org: It is not enough to change all 302s to
                303s because 302 is appropriate for most URIs.  So the purl.org
                maintainers would have to implement a feature for users to
                specify that some resource is a non-information resource.
                This would require changes to the database.  Are there any
                options to do a double redirection? I.e. if purl returns a
                302 redirect, then my own server does a 303.  On Jan 17, decided
                to clarify with TAG whether inferences are supposed to be made
                already on the initial response code.
                ACTION (DONE Jan 17): Alistair drafted the question (i.e., that only the
                initial response code matters) for discussion in BPD, then to send to TAG:
                This draft note to TAG
                -- suggests they coin a URI for class "resource"
                   (tag:informationResource) so that things like rdfs:Class,
                   owl:Class, and rdf:Property could be declared disjoint with it.
                -- requests clarification on what implication one can draw when
                   303 is returned as opposed to 200 ("X is a tag:infoResource").

                (Note: In follow-up, David Booth suggested
                a draft "HTTP URI-Identity-Algorithm",
                out of scope for the VM TF per se:

                ACTION - DONE: Alistair put the purl.org material into an Appendix.

         -- Specific recipes
            Recipe 3.  Interpretation of a fragment identifier in the
                       presence of 303 redirects is unclear, so recipe
                       should note that browser may or may not apply
                       fragment identifier to secondary URI.

         -- Editorial suggestions
            E1. Shorter URIs in the examples would be better.
                Alistair would rather leave the longer URIs for now because
                a UK server is configured to support them, see
                Ralph suggests using w3c URIs in the final version (with
                shorter URIs for the examples).

            E2. At the beginning of each recipe, say what the URIs would return.

                Alistair proposes to illustrate this graphically, so added images
                David Booth actually intended simply to spell out which URIs
                are redirected to.  Ralph wonders whether the images really add any
                new information.

                On Jan 18, Alistair reorganized recipes 1 and
                2, adding short description of outcomes as
                per Booth suggestion.  Added examples with
                expected outcomes for purpose of testing.
                Wants to organize the rest like this when
                IE6 bug resolved.

    3.2. Andreas Harth review
         -- The document has too many choices - suggests
            cutting down to 3 or 4 covering 80% of the cases.
         -- Suggests content negotiation instead of mod_rewrite
            modules.  Response at:
         -- Suggests mod_alias instead of mod_rewrite.
         -- Maybe put purl.org examples into an appendix.

4.  TAG httpRange-14 decision [10]

    There have been recent comments on the list about the TAG
    decision by David Booth: [11] summarizing best practice
    issues around the decision, [12] on minting http URIs,
    and [13] on 302 versus 303 redirects; by David Wood: [15]
    with a use case for RDF; and and by Jacco van Ossenbruggen
    [14], reviewing the comments by David Wood and David Booth.

    In BPD, the idea arose to write a TAG-like "finding"
    to explain the impact of the httpRange-14 decision.
    David Booth and David Wood wrote drafts independently.
    Probably not enough time in BPD to start a new document,
    so could they be incorporated into cookbook?  David Booth
    agreed to go to propose a short section for us to consider.
    General agreement that we should avoid getting too
    historical -- just cover practical results.  Some of
    what David Booth has written could plausibly be recast
    as introductory material on how to choose reasonable
    namespace names.

5.  Testing
    ACTION: Ralph to test recipes with W3C configuration.

6.  xml:base and hash URIs

    On Jan 20, Alistair discovered that if you put a hash at the end
    of the base URI, e.g.:
    the hash is ignored when constructing relative URIs.  Discussion followed.

7.  Recipe covering the case of very large vocabularies

    2006-01-24. In addition to the current five recipes,
    Alistair sees the need for a Recipe Six -- if only
    a placeholder with text outlining the problem -- for
    covering the scenario of very large vocabularies, where
    instead of serving an entire vocabulary in RDF one might
    want to serve bounded descriptions of individual terms.
    As the Cookbook would not provide a recipe for this case,
    it is an open question how this issue should be handled

8. 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

[10] http://lists.w3.org/Archives/Public/www-tag/2005Jun/0039.html
[11] http://lists.w3.org/Archives/Public/public-swbp-wg/2005Dec/0055.html
[12] http://lists.w3.org/Archives/Public/public-swbp-wg/2005Dec/0056.html
[13] http://lists.w3.org/Archives/Public/public-swbp-wg/2005Dec/0123.html
[14] http://lists.w3.org/Archives/Public/public-swbp-wg/2005Dec/0085.html
[15] http://lists.w3.org/Archives/Public/public-swbp-wg/2005Sep/0010.html

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 Tuesday, 31 January 2006 14:20:48 UTC