- From: Jonathan Marsh <jmarsh@microsoft.com>
- Date: Thu, 2 Dec 2004 07:18:02 -0800
- To: "Yalcinalp, Umit" <umit.yalcinalp@sap.com>, "David Booth" <dbooth@w3.org>
- Cc: <www-ws-desc@w3.org>
Yes, that task has been on my to-do list for a few weeks now, and I just haven't gotten to it yet... > -----Original Message----- > From: www-ws-desc-request@w3.org [mailto:www-ws-desc-request@w3.org] > On Behalf Of Yalcinalp, Umit > Sent: Thursday, December 02, 2004 6:17 AM > To: David Booth > Cc: www-ws-desc@w3.org > Subject: Media Types LC Issues > > > All, > > Dear All, > > Anish and I got together and identified the following 19 LC issues > posted in the media types public list. Please find them in this email. > > Jonathan, is it possible to convert them to actual issues so that they > are tracked formally. > > Cheers, > > -- umit > > ------------------------------------------------------ > > > > MTLC1) Normative/informative reference [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Please change the document so that it is clear which sections and > which > references are normative and which are informative." > > MTLC2) Editorial Note uses table markup but no tabular data [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "The document has several sections labeled "Editorial note", these use > table markup but do not really contain tabular data, please change the > markup to something else, e.g. <dl> or just a <p> with a <strong> > leading "Editorial note:". Also note that "Editorial note:" is not a > proper table summary (as specified in the summary attribute)." > > > MTLC3) Update reference to XML Infoset [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "The xml-infoset reference refers to the first edition of the > document, > please change it to refer to the second edition." > > MTLC4) Remove the use of charset parameter in example containing > text/xml [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 1 has an example "text/xml; charset=utf-16", please change > this > example to something else, use of text/xml is discouraged and for XML > documents using a charset parameter is claimed to be unnecessary and > harmful." > > MTLC5) Clarify the use of example.org and exampl.com [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 1.1 states > > Namespace names of the general form "http://example.org/..." and > "http://example.com/..." represent application or context-dependent > URIs [IETF RFC 2396]. > > Please clarify in the document what you mean here, the statement does > not really make sense to me." > > MTLC6) Namespace name too long and had dates [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 1.1 notes "http://www.w3.org/2004/11/xmlmime" is defined by > the > document, the namespace URI is too long and it generally makes little > sense to put dates into namespaces URIs, please change this at least > to > e.g. "http://www.w3.org/2004/xmlmime" to be consistent with a wide > range > of W3C namespaces URIs." > > MTLC7) Production rules for expectedMediaType [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 2.2 states > > The value and the meaning of the expectedMediaType attribute is > similar to the value allowed for the 'Accept' header defined by > HTTP > 1.1 specification, Section 14.1 [IETF RFC 2616] and MUST follow the > production rules defined in that section. The 'q' parameter defined > by > HTTP 1.1 specification, Section 3.9 [IETF RFC 2616] is allowed, but > other accept-extensions are not allowed. > > The production rule in RFC 2616 cannot be used here, it is defined in > terms of octets while the information item is a sequence of > characters. > In order to re-use the production rule you would need to define how to > map the characters to octets before attempting to match; the alternate > solution would be to create a new production rule that is defined in > terms of characters. > > Please change the section so that it is clear what the differences > are, > you note these are "similar" and cite one difference, but it is not > clear to me whether this is the only difference. > > Please change the section so that it is clear which production rule > you > actually mean, section 14.1 of RFC 2616 has several. It would seem > that > you mean the production rule for "Accept", but as that contains > "Accept:" you probably don't, so you might mean the Accept production > rule without the leading "Accept:" or media-range. > > Whatever you do, please ensure that parameters can be used, e.g. > > x:expectedMediaType = 'application/xhtml+xml;profile=http://...' > " > > MTLC8) Allow expectedMediaType to specify any XML document [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "It seems that re-using the Accept header syntax here makes it > impossible > to state that any kind of "XML" is accepted, I however think that this > is an important use case for such an attribute. It is often not > possible > to include XML documents in other XML documents (e.g. if the document > has a document type declaration). Using e.g. > > x:expectedMediaType = 'application/xml' > > would likely not work as e.g. image/svg+xml does not match. I think > the > syntax should be extended so that it is possible to express that XML > is > expected whatever type might be used. This would be useful e.g. for a > web service interface to the W3C Markup Validator. > > The attribute could allow a special string like > > x:expectedMediaType = 'xml' > > in place of a media-range, this would allow the W3C Markup Validator > to > use it like > > x:expectedMediaType = 'xml, text/html, text/sgml' > > If accept-extensions continues to be disallowed, please include a > rationale for the exclusion in the document." > > MTLC9) Allow expecteMediaType to contain '*' [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 3.1 states > > When the expectedMediaType annotation attribute has a wildcard > ("*") > or a list of acceptable media types, the schema SHOULD require the > contentType attribute to be present. > > This seems to imply that > > x:expectedMediaType = '*' > > would be allowed which does not seem to be the case. If the intention > is > to allow this syntax, please change the definition accordingly, if it > is > not allowed, please re-word the paragraph to make it clear what you > mean." > > MTLC10) Value of contentType and the range specified by > expectedMediaType [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 3.1 states > > The value of the contentType attribute, if present, SHOULD be > within > the range specified by the expectedMediaType annotation attribute, > if > specified in the schema. > > It is not clear to me how it is determined whether this requirement > has > been met. If there is an algorithm, please reference it normatively, > or > provide your own." > > MTLC11) Lexical and value space of the attributes and XML schema decl > [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Section 2.1 does not define the lexical or value space of the > attribute, > it states it is xs:string but it would seem you would rather want to > say > that this relates to RFC 2616 Content-Type in some way. When fixing > this > please consider my remarks about the "Accept:" header reference here, > too. > > The XML Schema for the attributes seems overly lax, for example, as > currently defined, x:expectedMediaType requires that the string has at > least three characters, please change the definition so that a XML > Schema Validator can determine conformance of the attribute value as > much as possible." > > MTLC12) Add NS prefix to all occurences of expecteMediaType and > contentType [1] > > Raised by Bjoern Hoehrmann on 2nd nov, 2004 > > "Please add a namespace prefix to all occurences of > "expectedMediaType" > and "contentType" in the document where you do not specifically refer > to > the local name of the attribute, this helps to avoid misunderstandings > by people not totally namespace-aware and make the document more > readable." > > MTLC13) Update XOP reference [2] > > Raised by Klotz Leigh on 3rd nov, 2004 > > "The reference to XOP in this Working Draft > http://www.w3.org/TR/2004/WD-xml-media-types-20041102/ is to the > Working > Draft revision of XOP at http://www.w3.org/TR/2004/WD-xop10-20040209/ > and > should be to the CR version http://www.w3.org/TR/2004/CR-xop10- > 20040826/ > as > it incorporates the xmlmime:contentType attribute defined in this > Working > Draft." > > MTLC14) How to distinguish between hexBinary and base64Binary in the > absence > of XML schema [3] > > Raised by John Cowan on 3rd nov, 2004 > > "The introduction to the 2 November 2004 Last Call WD of "Assigning > Media > Types to Binary XML" states that XML Schema is not required in order > to > make use of the xmlmime:contentType attribute. > > Unfortunately, without type information it is not possible to reliably > distinguish between elements with base64 binary and hex binary > content: > for example, the content "0000" decodes to the octets "0x00 0x00" in > hex binary, but "0xD3 0x4D 0x34" in base64 binary. > > Therefore, either an xmlmime:contentTransferEncoding is required for > schema-free operations, or the recommendation should specify the use > of > xsi:type with the values "xs:base64Binary" and "xs:hexBinary" for use > in schema-free operations. > > I would prefer the latter alternative." > > MTLC15) Bad namespace prefix [4] > > Raised by Paul Cotton on 4th nov, 2004 > > "Table 1. "Prefixes and Namespaces used in this specification" defines > the prefix "xmlmime" for the namespace URI > "http://www.w3.org/2004/11/xmlmime". This is an invalid namespace > prefix since a namespace prefix is not allowed to start with the > reserved string "xml". See [1]: > > === > Namespace Constraint: Leading "XML" > Prefixes beginning with the three-letter sequence x, m, l, in any case > combination, are reserved for use by XML and XML-related > specifications. > === > " > > MTLC16) Interop problems with Accept HTTP header[5] > > Raised by Larry Masinter on 4th Nov, 2004 > > ' > I'm suspicious of the attempt to use HTTP "accept" headers > to "indicate in XML Schema what media > type the character content of an element will have." > > In practice, HTTP Accept headers have turned out to have > severe interoperability problems, and have not been useful > for content negotiation. It's a bad practice to try to > follow something that hasn't worked for the stated purpose. > For example, a description of "image/*" is, in practice, > not useful because of the wide variety of image types > that are likely *not* implemented. > > In general, indicating ranges of acceptable media type > is quite difficult; the best practice in this area is > likely to be either CCPP (www.w3.org/Mobile/CCPP/) > or media feature expressions (RFC 2533 plus > RFC 2913). However, neither have widespread deployment > and interoperability experience. > ' > > MTLC17) ContentType of media type [5] > > Raised by Larry Masinter on 4th Nov, 2004 > > ' > I think the document suffers from an editorial > problem which starts with the title. "text/xml;charset=utf-8" > is not a "IANA media type" or a "media type token", it > is a "content-type string", the difference being that > a content-type string starts with a media type followed > by parameters for that type. > > I think it's important to avoid confusion by careful > editing: > > - The title: "Assigning Media Types to Binary" > probably should be "Describing Media Content of Binary" > > - The schema definition could be 'expectedContentType' > instead of 'expectedContentType' (if a single value; > if a more complex type expression language is allowed, > then rename accordingly). > > - "Declaring media types for binary data" > => "Declaring Content-Type for binary data". > > - "the name of an IANA media type token" => > "a valid content-type string" > ' > > MTLC18) Normalization for content-type strings [5] > > Raised by Larry Masinter on 4th Nov, 2004 > > ' > [normalized value]": I think defining a normalization for > content-type strings is difficult, and you should avoid it. > ' > > MTLC19) Why is contentType attribute required? [6] > > Raised by Ian Hickson on 18th nov, 2004 > > " > I am confused as to why the mime:contentType attribute is required. > > It would seem that applications that expect binary content will have > to > be > hardcoded to support the elements in which that content appears > anyway, > so > supporting an attribute on those elements as well seems like it > wouldn't > require the use of namespaces. > > As a data point: XLink is used in SVG on elements that refer to > external > resources, as in <style xlink:href="">. The theory is that by reusing > the > same attribute for all links, the implementation is somehow able to > reuse > code. However, in practice, the UAs have to have code for each > embedding > mechanism, and the attribute doesn't help at all by being in the XLink > namespace. > > So while I can understand that XML Schema may need to be extended to > support MIME types as a first-class data type, it would seem that the > actual mime:contentType attribute is superfluous. > " > > > [1] > http://lists.w3.org/Archives/Public/public-ws-media- > types/2004Nov/0000.h > tml > [2] > http://lists.w3.org/Archives/Public/public-ws-media- > types/2004Nov/0001.h > tml > [3] > http://lists.w3.org/Archives/Public/public-ws-media- > types/2004Nov/0002.h > tml > [4] > http://lists.w3.org/Archives/Public/public-ws-media- > types/2004Nov/0003.h > tml > [5] > http://lists.w3.org/Archives/Public/public-ws-media- > types/2004Nov/0006.h > tml > [6] > http://lists.w3.org/Archives/Public/public-ws-media- > types/2004Nov/0008.h > tml
Received on Thursday, 2 December 2004 15:18:26 UTC