About this document
This document lists known errata for each Recommendation.
Each entry has the following information:
- A unique identifier
- The date it was added to the errata page
- A classification of the error (e.g., editorial, clarification,
bug, known problem with the document itself)
- A short description of the problem and what part of the
Recommendation is affected.
- Any proposed corrections and whether those corrections would
affect conformance of documents or software
- Any normative corrections; see the section on Errata
Management in the W3C Process Document ([PROCESS]
section 7.6.1) for more information about normative corrections
Known Errors
- Identifier
- http://www.w3.org/2007/powder/powder-errata#mediaTypes
- Date
- 29 October 2009
- Error type
- Clarification
- Error description
- The POWDER and POWDER-S Internet Media Type/Macintosh File Type definitions
given in Appendices B and C of POWDER: Description Resources both
indicate that there are no optional parameters. This is incorrect as the
charset parameter may be included
exactly as defined for application/xml in RFC3023.
- Correction
- The POWDER and POWDER-S Internet Media Type/Macintosh File Type definitions are repeated
below with the optional
charset attribute included. This does not affect conformance.
- Normative Correction
- None
POWDER Internet Media Type and Macintosh File Type
The following Media Type has been submitted to the IESG for review, approval, and registration with IANA
- contact:
- Phil Archer or Matt Womer
- See also:
- How to Register a Media Type for a W3C Specification
- Internet Media Type registration, consistency of use
TAG Finding 3 June 2002 (Revised 4 September 2002)
The Internet Media Type / MIME Type for POWDER is "application/powder+xml".
It is recommended that POWDER files use the file extension of .xml (all lowercase) on all platforms.
It is recommended that POWDER files stored on Macintosh HFS file systems be given a file type of "TEXT".
- Type name:
- application
- Subtype name:
- powder+xml
- Required parameters:
- None
- Optional parameters:
- "charset": the parameter has identical semantics to the charset parameter of the "application/xml" media type as specified in [RFC3023], section 3.2.
- Encoding considerations:
- Identical to those of "application/xml" as specified in [RFC3023], section 3.2.
- Security considerations:
- POWDER is used to make assertions, sometimes socially sensitive,
about web resources. Consumers of POWDER should be aware of the
source and chain of custody of this data. Security considerations
for URIs (Section 7 of RFC 3986 [RFC3986]) and IRIs (Section 8 of RFC 3987 [RFC3987])
apply to the extent that describing resources in POWDER may prompt
consumers to retrieve those resources.
- Interoperability considerations:
- There are no known interoperability issues.
- Published specification:
- http://www.w3.org/TR/powder-dr/, modified by http://www.w3.org/2007/powder/powder-errata.html#mediaTypes
- Applications which use this media type:
- No known applications currently use this media type.
- Additional information:
- Magic number(s):
- As specified for "application/xml" in RFC 3023 [RFC3023], section 3.2.
- File extension(s):
- .xml
- Fragment identifiers:
- Identical to that of "application/xml" as described in RFC 3023 [RFC3023], section 5.
- Base URI:
- As specified in RFC 3023 [RFC3023], section 6.
- Macintosh file type code(s):
- "TEXT"
- Person & email address to contact for further information:
- public-powderwg@w3.org
- Intended usage:
- COMMON
- Restrictions on usage:
- None
- Author/Change controller:
- The POWDER specification is a work product of the World Wide Web
Consortium's Protocol for Web Description Resources (POWDER) Working
Group. The W3C has change control over these specifications.
POWDER-S Internet Media Type and Macintosh File Type
The following Media Type has been submitted to the IESG for review, approval, and registration with IANA
- contact:
- Phil Archer or Matt Womer
- See also:
- How to Register a Media Type for a W3C Specification
- Internet Media Type registration, consistency of use
TAG Finding 3 June 2002 (Revised 4 September 2002)
The Internet Media Type / MIME Type for POWDER-S is "application/powder-s+xml".
It is recommended that POWDER-S files use the file extension of .rdf (all lowercase) on all platforms.
It is recommended that POWDER-S files stored on Macintosh HFS file systems be given a file type of "TEXT".
- Type name:
- application
- Subtype name:
- powder-s+xml
- Required parameters:
- None
- Optional parameters:
- "charset": the parameter has identical semantics to the charset parameter of the "application/xml" media type as specified in [RFC3023], section 3.2.
- Encoding considerations:
- Identical to those of "application/xml" as specified in [RFC3023], section 3.2.
- Security considerations:
- POWDER-S is used to make assertions, sometimes socially sensitive,
about web resources. Consumers of POWDER should-S be aware of the
source and chain of custody of this data. Security considerations
for URIs (Section 7 of RFC 3986 [RFC3986]) and IRIs (Section 8 of RFC 3987 [RFC3987])
apply to the extent that describing resources in POWDER-S may prompt
consumers to retrieve those resources.
- Interoperability considerations:
- There are no known interoperability issues.
- Published specification:
- http://www.w3.org/TR/powder-dr/, modified by http://www.w3.org/2007/powder/powder-errata.html#mediaTypes
- Applications which use this media type:
- No known applications currently use this media type.
- Additional information:
- Magic number(s):
- As specified for "application/xml" in RFC 3023 [RFC3023], section 3.2.
- File extension(s):
- .rdf
- Fragment identifiers:
- Identical to that of "application/xml" as described in RFC 3023 [RFC3023], section 5.
- Base URI:
- As specified in RFC 3023 [RFC3023], section 6.
- Macintosh file type code(s):
- "TEXT"
- Person & email address to contact for further information:
- public-powderwg@w3.org
- Intended usage:
- COMMON
- Restrictions on usage:
- None
- Author/Change controller:
- The POWDER-S specification is a work product of the World Wide Web
Consortium's Protocol for Web Description Resources (POWDER) Working
Group. The W3C has change control over these specifications.
Misalignment of definition of wdrs:describedby cf. @rel describedby
- Identifier
- http://www.w3.org/2007/powder/powder-errata#describedby
- Date
- 8 November 2010
- Error type
- Clarification by removal of contradiction
- Error description
- Section 4.1 of the Description Resources document begins:
A given resource (hereafter known as the described resource) may relate itself to a POWDER document. There
are several methods to define such a relationship, detailed in the following sub-sections. To facilitate linking
between a described resource and a POWDER document we define a relationship type of describedby for
use in (X)HTML link elements, HTTP Link Headers and ATOM feeds; and a textually
identical term as part of the POWDER-S vocabulary. This is a generic relationship type that does not of itself imply
that the link points to a POWDER document — that is done by the specific Media type.
The formal definition of describedby is given in Appendix D.
The clear intention is the the @rel type of describedby and the RDF property wdrs:describedby are
semantically identical. This is reinforced in Section 4.1.1 where the text says:
The meaning of wdrs:describedby is identical to the describedby relationship type defined above so that:
http://www.w3.org/2007/05/powder-s#describedby
and
http://www.iana.org/assignments/relation/describedby
have the same meaning and could be used interchangeably although the context in which they are used will
usually determine which is the more appropriate.
Furthermore, Appendix D, the formal definition of the
describedby @rel type, states:
The relationship A 'describedby' B asserts that resource B provides a description of resource A.
There are no constraints on the format or representation of either A or B, neither are there any
further constraints on either resource.
However, Section 4.1.4 begins by asserting that wdrs:describedby has a domain of
wdrs:Document, i.e. that the object of a wdrs:property can be inferred to
be a POWDER document. This error is repeated in the
wdrs namespace document.
There is a clear misalignment between the two definitions that needs to be corrected. Both the
HTML and RDF Schema representations of the namespace document have been amended to remove the erroneous
range restriction on wdrs:describedby.
- Correction
- The beginning of section 4.1.4 should be amended as follows:
Current text:
We define the RDF property wdrs:describedby with a domain of
rdf:Resource and a range of wdrs:Document.
This is the class of POWDER documents and is a sub class of owl:Ontology. The meaning of
wdrs:describedby is identical to the describedby relationship type defined above so that:
Replacement text
We define the RDF property wdrs:describedby, the meaning of which is identical to the
describedby link relationship type defined above so that:
Removing the range restriction on wdrs:describedby is fully backwards compatible. The only
impact the change could have is on any existing implementations that infer that the object of a wdrs:describedby
property is a POWDER document. Although possible, this seems highly unlikely at the time of writing.
It is anticipated that this change will be reflected in the Description Resources document itself early in 2011 following the
implementation of a new change management process at W3C.
In the meantime, you are invited to send any comments on this change to public-powderwg@w3.org
(with public archive).
- Normative Correction
- None