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Re: [XHR] Use of the term 'MIME type'

From: Alex Milowski <alex@milowski.org>
Date: Wed, 26 Jan 2011 08:19:00 -0800
Message-ID: <AANLkTi=TM5i1-jp6yxHrS63SqofrKsW2kNfB+w-=s0bF@mail.gmail.com>
To: Anne van Kesteren <annevk@opera.com>
Cc: public-webapps@w3.org
On Wed, Jan 26, 2011 at 6:14 AM, Anne van Kesteren <annevk@opera.com> wrote:
> On Tue, 04 Jan 2011 03:56:31 +0100, Alex Milowski <alex@milowski.org> wrote:
>>
>> In reading through the current draft of XMLHttpRequest [1] I see a
>> consistent use of the term 'MIME type' instead of 'Media Type'  as
>> defined by RFC 2046 [2].  RFC 2046 does not define the term 'MIME
>> type' and only refers to 'MIME Media Type' once within the RFC
>> document.  Otherwise, it would seem the proper term is 'Media Type'.
>>
>> Further, the 'Content-Type' header used to type the MIME entity as
>> described as:
>>
>> "The Content-Type field is used to specify the nature of the data in
>> the body of a MIME entity, by giving media type and subtype
>> identifiers, and by providing auxiliary information that may be
>> required for certain media types."
>>
>> Again, it would seem the value is a 'Media Type' and not a 'MIME
>> type'.  I think it would be preferred for this specification and RFC
>> 2046 agreed on the data type name for the value of the Content-Type
>> header.
>
> As the terminology section states I am using MIME type per HTML5. The
> reasons why that specification uses that term are described here:
>
> http://www.whatwg.org/specs/web-apps/current-work/complete/infrastructure.html#mime-type
>
> If you disagree with those reasons you can file a bug against HTML5 and get
> the HTML WG to look at it. To make it not too much of a Kafkaesque process I
> am willing to provide assistance if you wish to do that and need help.

The definition of "MIME type" for HTML5 [1] is, in fact, broken.
Unless I'm missing something, it does not reference RFC 2046 and
define the term "MIME type" as having a value of a "media type".

I do think that the need to use the wrong term in the XMLHttpRequest
specification just because of a poor choice of names by the CSS
specification propagates inconsistency.   It is the CSS specification
that is inconsistent with the HTTP RFCs, RFC 2046, and every other
proper use of the term 'media type'.  As the XMLHttpRequest
specification deals with making HTTP requests, amongst others, it
would behoove the authors to use the term 'media type' in the RFC 2046
sense rather than try to be consistent with the inconsistent CSS
specification.

CSS's use of "media types" could easily be adjusted overtime to lessen
the use of the conflicted term.

I will file an issue about the definition of MIME type in HTML5 as it
needs to refer to "media type" in RFC 2046 properly.  I would love to
see them use "media type" instead of "MIME type" but I am not going to
hold my breath on that one.

[1] http://dev.w3.org/html5/spec/Overview.html#mime-types

-- 
--Alex Milowski
"The excellence of grammar as a guide is proportional to the paucity of the
inflexions, i.e. to the degree of analysis effected by the language
considered."

Bertrand Russell in a footnote of Principles of Mathematics
Received on Wednesday, 26 January 2011 16:19:33 GMT

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