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Issue 268 (Interop Problems with Accept header) Proposed Resolution

From: Yalcinalp, Umit <umit.yalcinalp@sap.com>
Date: Thu, 6 Jan 2005 01:22:54 +0100
Message-ID: <99CA63DD941EDC4EBA897048D9B0061D0F676DE5@uspalx20a.pal.sap.corp>
To: <www-ws-desc@w3.org>
Cc: <public-ws-media-types@w3.org>

The issue [1] questions the utility of the Accept header with respect to
content negotiation and interoperability. 

It seems to me that there is a slight confusion to the utility of the
expectedMediaType attribute. We are not defining a "protocol" or dynamic
"content negotation" with [2], we are just borrowing the definition of
the Accept header to define the range of media types that are allowed as
a "design time hint" to indicate what the content is expected to be. 

>From the web services design perspective, I don't view the utility of
the expectedMediaType attribute to negotiate the content, rather it is
to "declare" the content to be within a range of values by the
WSDL/Schema author. The WSDL document and the associated schema by using
the note would state statically what the probable range of media-types
that binary data may have. This gives enough hints to a consumer of a
WSDL document to know what the content is expected to be and whether the
content may be utilized in advance. Therefore, it is possible for a
client to make decisions about a web service, hence the associated
schema and media-type with binary document, based on the information in
WSDL. Since this hint is in the description, I observe that this
actually helps interoperability because the range of media types are
explicit in the description, rather than negotiated at runtime. 

I propose that we close this issue with no action. 

[1]
http://dev.w3.org/cvsweb/%7Echeckout%7E/2002/ws/desc/issues/wsd-issues-c
ondensed.html#x268
[2] http://www.w3.org/TR/xml-media-types/
Received on Thursday, 6 January 2005 00:23:30 GMT

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