Please can I have some help with the 'directory-locations' API

[Submitted by Richard Wallis on behalf of nfreear]

Hi,

My objective is to get the X number of libraries with the books/items given by the ISBN numbers nearest to my search location.

I'm using the 'holdings' service, and getting a response fine ([] replacement, line-breaks added):

http://api.talis.com/1/bib/holdings?api_key={MY_KEY}&isbn=1566195500+0590761161+0883012839+0893190055

[Holdings]
[holding name="Denbighshire, (part of NEWnet)" instCode="7009" identity="7009.inst" isbn="0590761161" /]
[holding name="Galway County Library" instCode="5009" identity="5009.inst" isbn="0590761161" /]
[holding name="Lancashire County Library" instCode="0003" identity="0003.inst" isbn="0590761161" /]
[holding name="Newcastle City Libraries" instCode="3002" identity="3002.inst" isbn="0590761161" /]
[holding name="Northamptonshire Libraries & Information Service" instCode="4046" identity="4046.inst" isbn="0590761161" /]
[holding name="Nottinghamshire County Council" instCode="4043" identity="4043.inst" isbn="0590761161" /]
[holding name="Rhondda Cynon Taff" instCode="7018" identity="7018.inst" isbn="0590761161" /]
[/Holdings]

However, when I try to feed the above URI to directory-locations, which is what I think I want, I get back an empty result:

http://api.talis.com/1/dir/locations?api_key=f00ae29c377c&search=Galway&uri=http%3A%2F%2Fapi.talis.com%2F1%2Fbib%2Fholdings%3Fapi_key%3Df00ae29c377c%26isbn%3D1566195500%2B0590761161%2B0883012839%2B0893190055"
[?xml version="1.0"?]
[rdf:RDF
xmlns:ad="http://schemas.talis.com/2005/address/schema#"
xmlns:dctype="http://purl.org/dc/dcmitype/"
xmlns:foaf="http://xmlns.com/foaf/0.1/"
xmlns:dct="http://purl.org/dc/terms/"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:ddd="http://schemas.talis.com/2005/ddd/db#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:dir="http://schemas.talis.com/2005/dir/schema#"
xmlns:sv="http://schemas.talis.com/2005/service/schema#"
xmlns:geo="http://www.w3.org/2003/01/geo/wgs84_pos#"
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:lib="http://schemas.talis.com/2005/library/schema#"]
[/rdf:RDF]

I've tried a postcode as the 'search' parameter too, but to no avail. And it seems that the spaces between ISBN numbers should be double url-encoded.

Am I using 'directory-locations' in the right way? Any ideas? Any help appreciated.
Thanks, Nick