How many extra
recordData fields will we have in the end? Users make use of a client. Clients
can be smart enough to deal with unknown fields (alert the user or whatever).
But users do not know that there are extra fields and clients will not request
for all available extra fields because clients do not understand the
semantics. Users do.
The extension
mechanism heavily relies on bilateral agreements and a priori knowledge and
raises the barrier for users to get extra information that is useful and
available.
Theo
Van:
SRU (Search and Retrieve Via URL)
Implementors [mailto:[log in to unmask]] Namens
Janifer Gatenby
Verzonden: vrijdag 28 maart 2008
16:31
Aan:
[log in to unmask]
Onderwerp:
Re: Price information in SRU
responses
You can
use extraRecordData to include price with any other resource description
scheme. According to SRU, the
client must know that you provide price as extraRecordData and must request it
else you may not send it.
See:
http://www.loc.gov/standards/sru/specs/common.html#extraData
Janifer
Gatenby
Research
integration and standards · OCLC B.V.
Schipholweg 99 · P.O. Box 876 · 2300 AW Leiden · The Netherlands t +31 71 524 6516 · m
+31 6 1710 2867 · f +31 71 522 31 19 e [log in to unmask] · w
www.oclc.org
From:
SRU (Search and Retrieve Via URL)
Implementors [mailto:[log in to unmask]] On Behalf
Of Ray Denenberg
Sent: 28 March 2008 16:19
To: [log in to unmask]
Subject: Re: Price information in
SRU
responses
Sorry Mike but you can't do that.
Not if we're talking about the DC schema
at:
http://www.loc.gov/standards/sru/resources/dc-schema.xsd
There
is no provision in that schema for non-dc elements.
(We could issue another version of the DC schema to
allow this, and if someone thinks it's a good idea I'll draft
it.)
----- Original Message -----
Sent:
Friday, March 28, 2008 11:01 AM
Subject: Price
information in SRU
responses
Yakov Shafranovich writes:
> I am
working on a SRU gateway for a
book publisher. One of the
> things I have run into is that
there is no way to pass pricing
> information in
SRU without using the ONIX
scheme. Is there a way to
> embed pricing information in
SRU responses using other
schemes?
Hi, Yakov. Sure, you can embed whatever information
you want in
records transferred via SRU, just as you can with any other
XML
document. Just add the elements you want wherever they make
most
sense in the record, and be sure to put them in a namespace other
than
that of the standardised part of the record. For
example:
<dc:record xmlns:dc='http://purl.org/dc/elements/1.1/'
xmlns:mike='...'>
<dc:identifier>12345</dc:identifier>
<dc:creator>Hillare Belloc</mike:remitter>
<dc:title>Poems for Bad Children</dc:title>
<mike:price>5.99</mike:price>
</request>
The
problem is: how do you get the client application to recognise
and
understand the extra information you've added? To make that
work, you
need an agreement between server and client about the format
of the
records -- in other words, the client needs to know that it will
not
just be getting DC records, but DC-extended-with-mike:price
records.
_/|_
___________________________________________________________________
/o
) \/ Mike Taylor <[log in to unmask]>
http://www.miketaylor.org.uk
)_v__/\
"A Linux system requires rebooting about as often as a Windoze
system
requires re-installing" -- David
Joffe.
