This is a tricky topic.

First, the only people who care what the prefix is are people who are
not using XML parsers.  If you're doing simple string parsing, then
having a reliable prefix is a godsend.  Personally, I'm not going to go
to a lot of effort for that particular community, however much I use
string parsing myself for quick-and-dirty data access.  Good XML parsers
are available in every programming language.

Second, we don't always have control over what prefix is used by
programmatically generated XML.  I see lots of crappy prefixes generated
by Axis and I have not been able to find a way to correct that.  I'm not
prepared to manually correct them all.

So, while it is easy to say we ought to be using consistent prefixes,
it's going to be hard to make happen universally.  And if you can't make
it universal, then the client programmer is going to eventually have to
do the right thing and get over counting on that fixed prefix.


-----Original Message-----
From: SRU (Search and Retrieve Via URL) Implementors
[mailto:[log in to unmask]] On Behalf Of Hammond, Tony
Sent: Friday, August 14, 2009 10:57 AM
To: [log in to unmask]
Subject: SRU 2.0 Draft Feedback: SRU Preferred Qnames


Ditto these comments I also posted to the
<[log in to unmask]> feedback list.




Forgot to add this point. There should be some mention (well, perhaps
than that) in the document about preferred SRU XML QNames for various

    * SRU response
    * Diagnostics
    * Facets
    * Search Result Analysis
    * etc.

Preferably there should be one single section and/or table listing out
namespace URIs and preferred XML QNames.

Having a preferred or "known" XML QName makes it easier on implementers,
rather than working with application generated placeholders.

Also a mistake not to offer guidance, e.g. the facet example is using a
defaulted namespace but this fragment would typically be embedded within
response which may itself be defaulted.

Less ambiguity all round if clear instructions on QNames are provided
recommendation to use them. This also becomes important as one consider
alternate serializations.

Also is there anything to be said re "srw" and "sru"? Version 1.* is
"srw", I think, whereas some newer docs (e.g. the ATOM example) are
"sru". There should be guidance. And maybe some historical note about

As a precedent on XML Qname changing note that Adobe intially used "xap"
(and xap*") in their XMP architecture but now explicitly prefer "xmp"
"xmp*") in their spec. (Still, some of their own tools persist in using
"xap*" forms.)



DISCLAIMER: This e-mail is confidential and should not be used by anyone
who is
not the original intended recipient. If you have received this e-mail in
please inform the sender and delete it from your mailbox or any other
mechanism. Neither Macmillan Publishers Limited nor any of its agents
liability for any statements made which are clearly the sender's own and
expressly made on behalf of Macmillan Publishers Limited or one of its
Please note that neither Macmillan Publishers Limited nor any of its
accept any responsibility for viruses that may be contained in this
e-mail or
its attachments and it is your responsibility to scan the e-mail and 
attachments (if any). No contracts may be concluded on behalf of
Publishers Limited or its agents by means of e-mail communication.
Publishers Limited Registered in England and Wales with registered
number 785998 
Registered Office Brunel Road, Houndmills, Basingstoke RG21 6XS