- From: Martin Duerst <duerst@it.aoyama.ac.jp>
- Date: Wed, 08 Aug 2007 10:32:39 +0900
- To: "McDonald, Ira" <imcdonald@sharplabs.com>, "David Dorward" <david@dorward.me.uk>, "Ernest Unrau" <ejunrau@mts.net>
- Cc: "www-validator Community" <www-validator@w3.org>, <www-international@w3.org>
It's very clear that the charset tags themselves are case-insensitive, i.e. US-ASCII is as good as us-ascii is as good as uS-aSCii or any other variant. It's also clear that for HTML, element and attribute names are case-insensitive. The question is whether the charset parameter on the Content-Type HTTP header is case-sensitive or case-insensitive. Olivier earlier said that he wasn't able to find anything relevant in the HTTP spec, but I found this at http://www.ietf.org/rfc/rfc2616.txt: >>>>>>>> 3.7 Media Types HTTP uses Internet Media Types [17] in the Content-Type (section 14.17) and Accept (section 14.1) header fields in order to provide open and extensible data typing and type negotiation. media-type = type "/" subtype *( ";" parameter ) type = token subtype = token Parameters MAY follow the type/subtype in the form of attribute/value pairs (as defined in section 3.6). The type, subtype, and parameter attribute names are case- insensitive. Parameter values might or might not be case-sensitive, depending on the semantics of the parameter name. >>>>>>>> "charset" is a parameter attribute name, and therefore case-insensitive. Section 3.7 is clearly referenced from Section 14.7: >>>>>>>> 14.17 Content-Type The Content-Type entity-header field indicates the media type of the entity-body sent to the recipient or, in the case of the HEAD method, the media type that would have been sent had the request been a GET. Content-Type = "Content-Type" ":" media-type Media types are defined in section 3.7. An example of the field is Content-Type: text/html; charset=ISO-8859-4 Further discussion of methods for identifying the media type of an entity is provided in section 7.2.1. >>>>>>>> Olivier said that "the rest of HTTP constructs" are case-sensitive, but this is not true. Methods such as GET and PUT are case-sensitive, but most of the other stuff is not because it was taken over from email, where it is also not case-sensitive. Regards, Martin.s At 04:33 07/08/08, McDonald, Ira wrote: > >Hi, > >Quoting HTTP/1.1 (RFC 2616), page 22: > >>> "HTTP character sets are identified by case-insensitive tokens. The > complete set of tokens is defined by the IANA Character Set registry > [19]." > >And the normative IANA Charset Registration Procedures (RFC 2978), >page 4 says: > > "Finally, charsets being registered for use with the "text" media type > MUST have a primary name that conforms to the more restrictive syntax > of the charset field in MIME encoded-words [RFC-2047, RFC-2184] and > MIME extended parameter values [RFC-2184]. A combined ABNF > definition for such names is as follows: > > mime-charset = 1*mime-charset-chars > mime-charset-chars = ALPHA / DIGIT / > "!" / "#" / "$" / "%" / "&" / > "'" / "+" / "-" / "^" / "_" / > "`" / "{" / "}" / "~" >>> ALPHA = "A".."Z" ; Case insensitive ASCII Letter > DIGIT = "0".."9" ; Numeric digit" > >Any use of IANA charset tags in any standard that is case >sensitive is broken. > >Cheers, >- Ira - editor of IANA Charset MIB (RFC 3808) > >Ira McDonald (Musician / Software Architect) >Chair - Linux Foundation Open Printing WG >Blue Roof Music / High North Inc >PO Box 221 Grand Marais, MI 49839 >phone: +1-906-494-2434 >email: imcdonald@sharplabs.com > >-----Original Message----- >From: www-international-request@w3.org >[mailto:www-international-request@w3.org]On Behalf Of David Dorward >Sent: Tuesday, August 07, 2007 2:59 AM >To: Ernest Unrau >Cc: www-validator Community; www-international@w3.org >Subject: Re: Validator case-sensitive bug for CHARSET? > > > >On 7 Aug 2007, at 08:11, Ernest Unrau wrote: >> No HTML tags are case-sensitive, but it may indeed be that the CHARSET >> parameter must be case sensitive since I'm told that the META tags are >> mimicking HTML headers. Perhaps the servers that parse these >> headers are >> also case sensitive? But one would think that validation would fail on >> other META tags also. > >There aren't any other meta tags that provide information needed in >order to parse a document, so that isn't the case. > >-- >David Dorward >http://dorward.me.uk/ >http://blog.dorward.me.uk/ > > > > >No virus found in this outgoing message. >Checked by AVG Free Edition. >Version: 7.5.476 / Virus Database: 269.11.8/940 - Release Date: 8/6/2007 4:53 PM > #-#-# Martin J. Du"rst, Assoc. Professor, Aoyama Gakuin University #-#-# http://www.sw.it.aoyama.ac.jp mailto:duerst@it.aoyama.ac.jp
Received on Wednesday, 8 August 2007 01:34:18 UTC