Help with parsing configuration using SolrParams/NamedList

[Jay Luker <lb...@reallywow.com>]

Hi,

I'm trying to use a CustomSimilarityFactory and pass in per-field
options from the schema.xml, like so:

 <similarity class="org.ads.solr.CustomSimilarityFactory">
    <lst name="field_a">
        <int name="min">500</int>
        <int name="max">10000</int>
        <float name="steepness">0.5</float>
    </lst>
    <lst name="field_b">
        <int name="min">500</int>
        <int name="max">20000</int>
        <float name="steepness">0.5</float>
    </lst>
 </similarity>

My problem is I am utterly failing to figure out how to parse this
nested option structure within my CustomSimilarityFactory class. I
know that the settings are available as a SolrParams object within the
getSimilarity() method. I'm convinced I need to convert to a NamedList
using params.toNamedList(), but my java fu is too feeble to code the
dang thing. The closest I seem to get is the top level as a NamedList
where the keys are "field_a" and "field_b", but then my values are
strings, e.g., "{min=500,max=10000,steepness=0.5}".

Anyone who could dash off a quick example of how to do this?

Thanks,
--jay

Re: Help with parsing configuration using SolrParams/NamedList

[Markus Jelsma <ma...@openindex.io>]

Hi,

The params you have suggest you're planning to use SweetSpotSimilarity. There 
already is a factory you can use in Jira.

https://issues.apache.org/jira/browse/SOLR-1365

Cheers,
> Hi,
> 
> I'm trying to use a CustomSimilarityFactory and pass in per-field
> options from the schema.xml, like so:
> 
>  <similarity class="org.ads.solr.CustomSimilarityFactory">
>     <lst name="field_a">
>         <int name="min">500</int>
>         <int name="max">10000</int>
>         <float name="steepness">0.5</float>
>     </lst>
>     <lst name="field_b">
>         <int name="min">500</int>
>         <int name="max">20000</int>
>         <float name="steepness">0.5</float>
>     </lst>
>  </similarity>
> 
> My problem is I am utterly failing to figure out how to parse this
> nested option structure within my CustomSimilarityFactory class. I
> know that the settings are available as a SolrParams object within the
> getSimilarity() method. I'm convinced I need to convert to a NamedList
> using params.toNamedList(), but my java fu is too feeble to code the
> dang thing. The closest I seem to get is the top level as a NamedList
> where the keys are "field_a" and "field_b", but then my values are
> strings, e.g., "{min=500,max=10000,steepness=0.5}".
> 
> Anyone who could dash off a quick example of how to do this?
> 
> Thanks,
> --jay