- From: Danny Ayers <danny.ayers@gmail.com>
- Date: Sun, 11 Feb 2007 22:01:32 +0100
- To: "Harry Halpin" <hhalpin@ibiblio.org>
- Cc: public-grddl-wg <public-grddl-wg@w3.org>
re. http://www.w3.org/2004/01/rdxh/spec Revision: 1.206 Overall I think it's pretty close to what's required to go to Last Call, but there are quite a few not-major editorial changes I'd suggest (below). One query on a green box, entirely possible I'm misreading that. [I've raised this in another email thread] The only significant thing maybe lacking is informative material specifically on GRDDL's recursion - maybe a sentence or two added to the end of the introduction (suggestion inline below) plus a paragraph entitled something like "Recursion Stopping Conditions". Cheers, Danny. --- *** Abstract "glean" is used many times without definition, and it isn't clear that "Resource Descriptions" and "data" are synonymous as used here (and "Dialects" is a bit confusing too - see below). A little rewording might help, e.g. [[ This GRDDL specification introduces markup for declaring that an XML document includes gleanable data and for linking to algorithms, typically represented in XSLT, for gleaning the resource descriptions from the document. ]] => [[ This GRDDL specification introduces markup based on existing standards for declaring that an XML document includes data compatible with the Resource Description Framework (RDF) and for linking to algorithms (typically represented in XSLT), for extracting this data from the document. ]] last sentence [[ A GRDDL Primer demonstrates the mechanism on XHTML documents which include widely-deployed dialects, more recently known as microformats. ]] - maybe strike ", more recently" *** Table of Contents ... 4. The GRDDL profile for XHTML 5. GRDDL for HTML Profiles ... - could those headings be made a bit more explicit (to sound less similar)? Seems potentially confusing. *** 1. Introduction: Data and Documents I think "dialect" needs a little pinning down somewhere, maybe here: [[ There are many dialects of languages in practice among the many XML documents on the web. ]] => [[ There are many domain-specific languages ("dialects") used in practice among the many XML documents on the web. ]] (Dunno : are iTunes and Audioscrobbler different XML languages? Different dialects of the XML language? Different domain languages expressed in XML? The same domain language expressed in different dialects?) The examples could do with a line of introduction, something like: [[ The following are examples of how the same musical work might be described in different XML dialects: ]] and followed by: [[ Although the examples describe the exact same thing, as it stands there's no clear mechanism through which computer software might be able to make this connection. ]] The RDF/XML example doesn't declare the dc namespace. Also, might it be preferable to show this as Turtle/N3, to make it clearer that is isn't just some weird kind of canonical XML expression? (Or at least add another sentence to stress the point). @prefix foaf: <http://xmlns.com/foaf/0.1/> . @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . @prefix dc: <http://purl.org/dc/elements/1.1/> . <http://musicbrainz.org/mm-2.1/album/6b050dcf-7ab1-456d-9e1b-c3c41c18eed2> dc:title "Are You Experienced?"; foaf:maker <http://musicbrainz.org/mm-2.1/artist/33b3c323-77c2-417c-a5b4-af7e6a111cc9> . <http://musicbrainz.org/mm-2.1/artist/33b3c323-77c2-417c-a5b4-af7e6a111cc9> a foaf:Agent; foaf:name "The Jimi Hendrix Experience" . Again there's no intro for the markup, suggestion: [[ Here's the information contained in the XML fragments above, this time expressed as RDF: ]] outro - [[ Both the entities (subject and object resources) and relationships (predicates) are identified using unambiguous URIs. ]] [[ GRDDL stands for Gleaning Resource Descriptions from Dialects of Languages. That is, GRDDL provides a relatively inexpensive mechanism for bootstrapping RDF content from uniform XML dialects; shifting the burden from formulating RDF to creating transformation algorithms specifically for each dialect. ]] => [[ The publishers of the XML above could also provide the same data in RDF using RDF/XML or one of the other RDF syntaxes. GRDDL provides a relatively inexpensive mechanism for bootstrapping RDF content from uniform XML dialects; shifting the burden from formulating RDF to creating transformation algorithms specifically for each dialect. ]] *** Faithful Renditions [[ By specifying a GRDDL transformation, the author of a document states that the transformation will provide a faithful rendition of the source document, or some portion of the source document, that preserves its meaning in RDF. ]] I think that's potentially misleading, maybe better something like: [[ By specifying a GRDDL transformation, the author of a document states that the transformation will provide a faithful rendition in RDF of information (or some portion of the information) expressed through the XML dialect used in the source document. ]] Same again, but given a change in the above, less needs saying: [[ Likewise, by specifying a GRDDL namespace transformation or profile transformation, the creator of that namespace or profile states that the transformation will provide a faithful rendition of a class of source documents which relate to that namespace or profile, or some portion of such a source document, that preserves its meaning in RDF. A namespace document or a profile document also provide a means for their authors to explain, prosaically, the purpose of the transformation or any policy statements. ]] => [[ Likewise, by specifying a GRDDL namespace transformation or profile transformation, the creator of that namespace or profile states that the transformation will provide a faithful RDF rendition of a class of source documents which relate to that namespace or profile. A namespace document or a profile document also provide a means for their authors to explain in prose the purpose of the transformation or any policy statements. ]] *** GRDDL Primer This should maybe moved to a "Related Documents" block, somewhere near the start. [[ ...It develops on a number of examples... ]] strike "on" *** GRDDL Use Cases This should maybe moved to a "related documents" block, somewhere near the start. [[ The use cases document[usecases] collects a number of use cases together with their goals and requirements for GRDDL. These use cases also illustrate how XML and XHTML documents can be decorated with microformat, Embedded RDF or RDFa statements to support GRDDL transformations in charge of extracting valuable data that can then be used to automate a variety of tasks. ]] => [[ This document [usecases] collects a number of use cases together with their goals and requirements for GRDDL. It also illustrates how XML and XHTML documents can be decorated with microformat, Embedded RDF or RDFa statements to support GRDDL transformations to enable the extraction of valuable data that can then be used to automate a variety of tasks. ]] *** GRDDL Specification - redundant? !! Maybe add: [[ *** GRDDL Recursion The mechanisms of GRDDL which will be described in the next section enable the interpretation of either an individual XML/HTML document, or a whole class of documents as RDF. In the latter case the association between individual documents and the appropriate transformations is done indirectly through linkage (dereference over HTTP). The documents specifying which transformations to apply may themselves need transformation from an XML/HTML dialect to RDF to make this information available. Hence in the general case recursion through multiple layers of linked documents may be required to complete a faithful RDF rendition of a source document. This recursion should be transparent to end-users of GRDDL-enabled systems, but is something implementers of GRDDL-enabled systems will need to consider. ]] *** 2. Adding GRDDL to well-formed XML [[ The general form of associating a GRDDL transformation link with a well-formed XML document is by adding... ]] strike "by" [[ ...This method is suitable for use with any XML dialects that can accomodate an extra attribute on the root element. ]] => [[ ...This method is suitable for use with any XML dialects that can accomodate an extra namespace-qualified attribute on the root element. ]] "information resource" is used in the second green box - ref. WebArch Section 2.2. *** 3. Using GRDDL with XML Namespace Documents the green box on namespace transformations doesn't seem quite right - [[ If * an information resource NSDOC, identified by a URI NS, represented by an XML document with root node NODE with a GRDDL result that includes a triple whose o subject is NSDOC, whose o predicate is the property <http://www.w3.org/2003/g/data-view#namespaceTransformation>, and whose o object is TX, * and an information resource IR has an XML representation whose root element's namespace name is NS, then TX is a GRDDL transformation of NODE. ]] Presumably this needs an "there exists" inserting, but aside from that - second clause: "and an information resource IR has an XML representation whose root element's namespace name is NS" what has this to do with the right-hand side of the implication? 4. Using GRDDL with valid XHTML I'd be tempted to shift the "Stated more formally:" green boxes past the first example - the informal paragraph is pretty confusing itself. The second & third green boxes - defining "profile" & "typed link" - appear to be formalisations of part of a spec cited normatively, which seems back-to-front - is a comment needed? (HTML4 is pretty loose on those point ;-) 5. GRDDL for HTML Profiles (seems ok apart from an @@ already marked) 6. Transformation Algorithms [[ Developers of transformations should make available representations in widely-supported formats. ]] Doesn't sound right. Not sure why... [[ While javascript, C, or any other programming language technically expresses the relevant information, XSLT is specifically designed to express XML to XML transformations and has some good safety characteristics. ]] => [[ While technically Javascript, C, or virtually any other programming language could be used to express transformations for GRDDL, XSLT is specifically designed to express XML to XML transformations and has some good safety characteristics. ]] If this is true, it should be bolder! [[ When an information resource is represented by an XML document, the corresponding XPath data model is somewhat under-determined, depending on, for example, whether an agent elaborates inclusions, parameter entities, fixed and default attributes, or checks digital signatures. ]] => [[ When an information resource is represented by an XML document, the corresponding XPath data model may not be fully determined, depending on, for example, whether an agent elaborates inclusions, parameter entities, fixed and default attributes, or checks digital signatures. ]] This, and the material that follows "Put another way..." tends toward the discursive/informative, should maybe be broken out into a separate section, following the more normative material. 7. Security considerations Seems ok, except the caching section isn't really relevant - break out to an appendix: "Notes for Implementors"?? 7. (should be 8.) The GRDDL Vocabulary There's already an @@, looks like it's on DanC's plate - I assume an RDF/XML version will follow... 8. There is no 8. 9. References Can this section be moved /after/ the appendices? I nearly overlooked the content that follows it. [[ Parts of the following specifications are include in this one by reference: ]] - strike (or find better boilerplate) *** Appendix: A GRDDL-aware Agent protocol trace I like it ;-) Could a line be added saying which tools were used to create the trace? (/me wonders if DanC favours telnet as a browser) *** Appendix: Transformations for Styling versus data extraction Can't say I like this as it stands in this position, but can't think how to improve. *** Appendix: Issues - *** Appendix: Implementation Experience: Test Cases, Software, and Services Maybe move this together with any other related material into a "Note for Implementors" appendix *** Acknowledgements and Change History - -- http://dannyayers.com
Received on Sunday, 11 February 2007 21:01:39 UTC