Re: Request for guidance on MIME and media types

Speaking personally,

> - [email protected] is a coordination list, not necessarily for
>   direct technical discussion. If the conclusion that you have come
>   to is that you need to register a new Media Type, then I think
>   you should just go forward and do that via the usual channels,
>   and assure it gets reviewed e.g. on [email protected].

Understood; there was a desire to do it 'by the numbers' and make sure 
there was awareness of this at the proper places in the W3C. My 
anticipation would be that ietf-types is the next step.

> - I have read "resolve the URI to insert binary characters" below.
>   This is rather worrying, because to me it sounds like "square
>   circles". I have looked at the actual Miffy spec [3], and
>   have seen similar confusing language. I haven't seen a worked-out
>   example that would allow me to propose more precise language.

[...]

>> Note that a specification is being prepared that allows for the use 
>> of a similar "resolve the URI to insert binary characters" idiom in 
>> non-SOAP scenarios.

I think our intent here was closer to "use URIs to obtain 
representations that are included into the XML document with an 
encoding like base64 to assure that it remains well-formed." SVG (which 
I believe currently uses data: URIs) is one possible consumer of this.

A simplistic example might be;

---8<---
MIME-Version: 1.0
Content-Type: Multipart/Related; boundary=MIME_boundary; 
type=application/soap_mtom+xml;
         start="<[email protected]>"

--MIME_boundary
Content-Type: application/soap_mtom+xml
Content-Transfer-Encoding: 8bit
Content-ID: <[email protected]>

<?xml version='1.0' ?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="...">
<SOAP-ENV:Body>
   <!--- xml content here -->
   <Image type="image/jpeg"><Include xmlns="..."
     href="cid:[email protected]"/></Image>
   <!--- xml content here -->
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>

--MIME_boundary
Content-Type: image/jpeg
Content-Transfer-Encoding: binary
Content-ID: <[email protected]>

[binary image]
--MIME_boundary--
---8<---

Which could be transformed to this XML -

---8<---
<?xml version='1.0' ?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="...">
<SOAP-ENV:Body>
   <!--- xml content here -->
   <Image type="image/jpeg">[base64-encoded image]</Image>
   <!--- xml content here -->
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
---8<---

Is that helpful?

Cheers & thanks,

--
Mark Nottingham   Principal Technologist
Office of the CTO   BEA Systems