MultiWords Synonyms with ShingleFilterFactory and SynonymGraphFilterFactory in SolR 9.2.1

[elisabeth benoit <el...@gmail.com>]

Hello,

I'm trying to find a solution for multiwords synonyms in solr 9.2.1.

We cannot use sow=false because our different fields have different
stopwords and synonyms, ie they are not consistently analyzed and we dont
want SolR to use a field centric query ((as explained here:
https://opensourceconnections.com/blog/2018/02/20/edismax-and-multiterm-synonyms-oddities/
).

I'm trying the solution described here (
https://opensourceconnections.com/blog/2016/12/02/solr-elasticsearch-synonyms-better-patterns-keyphrases/)
but in SolR instead of ES, so I have a field define as

<fieldType name="multiwords_synonyms" class="solr.TextField"
positionIncrementGap="100">
     <analyzer type="index">
         <tokenizer name="standard" />
         <charFilter class="solr.MappingCharFilterFactory"
mapping="mapping-ISOLatin1Accent.txt" />
         <filter name="lowercase"/>
     </analyzer>
     <analyzer type="query">
         <tokenizer name="standard" />
         <charFilter class="solr.MappingCharFilterFactory"
mapping="mapping-ISOLatin1Accent.txt" />
         <filter name="lowercase" />
         <filter class="solr.ShingleFilterFactory" maxShingleSize="3"
minShingleSize="3" outputUnigrams="false"/>
         <filter class="solr.SynonymGraphFilterFactory"
synonyms="multiwords_synonyms.txt" ignoreCase="true"
                 expand="true"/>
         <filter name="flattenGraph"/>
         <filter class="solr.KeepWordFilterFactory"
words="has_multiwords_synonym.txt" />
     </analyzer>
 </fieldType>



Where multiwords_synonyms.txt contains the line

hotel\ de\ ville=>mairie

but it doesnt work on the query side, with the query "hôtel de ville
paris" I have the shingle "hotel de ville" but the synonym hotel\ de\
ville=>mairie doesnt match with the ShingleFilterFactory output.

If someone has a clue it would be greatly appreciated.

Best regards,

Elisabeth