- From: <vojtech.toman@emc.com>
- Date: Thu, 2 Feb 2012 07:44:19 -0500
- To: <public-xml-processing-model-wg@w3.org>
> -----Original Message----- > From: Norman Walsh [mailto:ndw@nwalsh.com] > Sent: Thursday, February 02, 2012 1:17 PM > To: public-xml-processing-model-wg@w3.org > Subject: Re: V.next: Use case: XQuery inputs ... > > "vojtech.toman@emc.com" <vojtech.toman@emc.com> writes: > > Btw, the support for application/xquery in p:xquery is one of the > > things that I am going to talk about at XML Prague. But as Alex says, > > it depends on XProc supporting multiple media types. > > Support for media types doesn't sound like its necessarily a big item, > can you outline how you do it? (Or should I just wait until next > weekend :-) It is based on shimming. It is no rocket science: Steps declare what media types they expect on their input ports, and what media types they produce on the output ports. If data of media type A arrives on an input port that accepts media type B, the processor converts the data from A to B (if it knows how to do that). In the case of p:xquery, the "query" input port is declared as accepting application/xml (for backward compatibility with the XProc specification). When data of media type application/xquery arrives on the "query" input port, the processor converts it to application/xml by wrapping it in a c:query wrapper (the actual implementation of this can, obviously, skip the wrapping and pass the raw query string to the p:xquery step directly). You could also imagine an alternative scheme where the "query" input would be declared as accepting application/xquery and if an XML document arrived on the "query" port, the processor would convert it to XQuery by taking the string value of the document element. I should note that shimming is only part of my paper. The more interesting part, I think, are the implications of this on XPath in XProc. Regards, Vojtech -- Vojtech Toman Consultant Software Engineer EMC | Information Intelligence Group vojtech.toman@emc.com http://developer.emc.com/xmltech
Received on Thursday, 2 February 2012 12:45:08 UTC