W3C home > Mailing lists > Public > xml-dist-app@w3.org > January 2002

Re: Media type encoding parameter?

From: Mark Baker <distobj@acm.org>
Date: Thu, 3 Jan 2002 08:40:02 -0500 (EST)
Message-Id: <200201031340.IAA00903@markbaker.ca>
To: jacek@systinet.com (Jacek Kopecky)
Cc: xml-dist-app@w3.org
Jacek,

>  > That isn't a requirement of a media type parameter.  "charset" is also
>  > not used to dispatch.
> 
>  I'm not sure here, but I think the charset may not be indicated
> by the XML document itself and it must be known somehow. Anyway,
> the charset (in the extreme) is necessary before even parsing the
> text because in a strange charset the angle brackets can be
> something completely other than ASCII angle bracket
> representation. So without this knowledge you wouldn't even be
> able to read the XML.

Not exactly true, since there are ways to recognize XML as a data
stream without metadata (see RFC 3023 and the XML Rec, sec 4.4.3).
But my point in bringing it up was to show that it isn't required
that a parameter be used to make dispatching decisions, as you
stated.

>  On the other hand namespaces or any other XML information from
> the document is always in the document.

True, but being available in the body does not preclude it from
being made available elsewhere.  Sometimes there are practical
considerations.

>  If I take your words literally, you again want every bit of the
> message outside of the envelope, for generally every bit of the
> message can affect success or failure of processing.

That doesn't follow.  Not every bit of a SOAP message can affect the
processing of a message.  For example, a SOAP processor isn't required
to look at the bits in the body block.

The only bits I'm interested in *considering* to be copied outside the
envelope are the ones that might cause faults.  See part 1 sec 4.4.5
for that list.

>  So I think you meant to say "...any reasonable and prudent
> information that impacts..."

I thought I was saying that, but ok.

> and now we could argue about what's
> reasonable and prudent outside of the envelope. I say, for SOAP,
> nuffin'. If we were talking about a parameter of a type
> application/xml, that would be different, for the root namespace
> could be useful indeed.

How would that be different?

> Even though, AFAIK, encodingStyle is commonly used on the body
> and there is usually only one, I dislike the trouble we'd get
> into in trying to handle the unusual and uncommon cases. Once
> there is only one something, like the root namespace of an XML
> document, I'm OK with optionally indicating it outside of the
> envelope, too,

There can be more than one namespace too.  We could refer to the
"root encodingStyle", and treat is we would the "root namespace".
I don't see the difference between the two.

> but again, for a generic MIME type, not for
> application/soap[+xml].

MB
-- 
Mark Baker, Chief Science Officer, Planetfred, Inc.
Ottawa, Ontario, CANADA.      mbaker@planetfred.com
http://www.markbaker.ca   http://www.planetfred.com
Received on Thursday, 3 January 2002 08:39:37 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:59:05 GMT