On Sep 27, 2007, at 2:50 PM, Chris Hostetter wrote:
to answer the broader question of using customized
LUcene SortComparatorSource objects in solr -- it is in fact possible.
In Solr, all decisisons about how to sort are driven by
FieldTypes. You
can subclass any of the FieldTypes that come with Solr and override
just
the getSortField method to use whatever sort logic you want and
then use
your new FieldType as you would any other plugin...
http://wiki.apache.org/solr/SolrPlugins
In the case where you have a custom SortComparatorSource that is not
"field" specific (or uses data from morethen one field) you would
need to
make your field type smart enough to let you cofigure (via the
<fieldType>
declaration in the schema) which fields (if any) to get it's data
from,
and then create a marker field of that type, which you don't use to
index
or store any data, but you use to indicate when to trigger your custom
sort logic, ie...
<fieldType name="distance" class="solr.YourField"
latFieldName="latitude" lonFieldName="longitute"
stored="false" indexed="false />
...
<field name="latitude" type="sint" indexed="true" stored="true" />
<field name="latitude" type="sint" indexed="true" stored="true" />
<field name="distance" type="distance" />
...and then use "sort=distance+asc" in your query
Using something like this, how would the custom SortComparatorSource
get a parameter from the request to use in sorting calculations?
I haven't looked under the covers of the local-solr stuff that flew
by earlier, but looks quite well done. I think I can speak for many
that would love to have geo field types / sorting capability built
into Solr.
Erik
