Solr Phonetic Search Highlight issue in search results

[Soumyanayan Kar]

When we are issuing a query with Phonetic Search, it is returning the
correct documents but not returning the highlights. When we use Stemming or
Synonym searches we are getting the proper highlights.

 

For example, when we execute a phonetic query for the term
fakt(ContentSearchPhonetic:fakt) in the Solr Admin interface, it returns two
documents containing the term "fact"(phonetic token equivalent), but the
list of highlights is empty as shown in the response below.

 

    <response>

    <lst name="responseHeader">

    <int name="status">0</int>

    <int name="QTime">16</int>

    <lst name="params">

      <str name="q">ContentSearchPhonetic:fakt</str>

      <str name="wt">xml</str>

    </lst>

  </lst>

    <result name="response" numFound="2" start="0">

        <doc>

          <long name="DocId">1</long>

          <str name="DocTitle">Doc 1</str>

          <str name="Content">Anyway, this game was excellent and was well
worth the time.  The graphics are truly amazing and the sound track was
pretty pleasant also. The  preacher was in  fact a thief.</str>

          <long name="_version_">1430480998833848320</long>

        </doc>

        <doc>

          <long name="DocId">2</long>

          <str name="DocTitle">Doc 2</str>

          <str name="Content">stunning. The  preacher was in  fact an
excellent thief who  had stolen the original manuscript of Hamlet  from an
exhibit on the  Riviera, where  he also  acquired his remarkable and
tan.</str>

          <long name="_version_">1430480998841188352</long>

        </doc>

      </result>

      <lst name="highlighting">

        <lst name="1"/>

        <lst name="2"/>

      </lst>

    </response>

 

Relevant section of Solr schema:

 

    <field name="DocId" type="long" indexed="true" stored="true"
required="true"/>

    <field name="DocTitle" type="string" indexed="false" stored="true"
required="true"/>

    <field name="Content" type="text_general" indexed="false" stored="true"
required="true"/>

    

    <field name="ContentSearch" type="text_general" indexed="true"
stored="false" multiValued="true"/>

    <field name="ContentSearchStemming" type="text_stem" indexed="true"
stored="false" multiValued="true"/>

    <field name="ContentSearchPhonetic" type="text_phonetic" indexed="true"
stored="false" multiValued="true"/>

    <field name="ContentSearchSynonym" type="text_synonym" indexed="true"
stored="false" multiValued="true"/>

    

    <uniqueKey>DocId</uniqueKey>

    <copyField source="Content" dest="ContentSearch"/>

    <copyField source="Content" dest="ContentSearchStemming"/>

    <copyField source="Content" dest="ContentSearchPhonetic"/>

    <copyField source="Content" dest="ContentSearchSynonym"/>

    

    <fieldType name="text_stem" class="solr.TextField" >

      <analyzer>

         <tokenizer class="solr.WhitespaceTokenizerFactory"/>

         <filter class="solr.SnowballPorterFilterFactory"/>

      </analyzer>          

    </fieldType>

    

    <fieldType name="text_phonetic" class="solr.TextField" >

      <analyzer>

         <tokenizer class="solr.WhitespaceTokenizerFactory"/>

         <filter class="solr.PhoneticFilterFactory"
encoder="DoubleMetaphone" inject="false"/>

      </analyzer>          

    </fieldType>

    

    <fieldType name="text_synonym" class="solr.TextField" >

    <analyzer>

      <tokenizer class="solr.WhitespaceTokenizerFactory"/>

      <filter class="solr.SynonymFilterFactory" synonyms="synonyms.txt"
ignoreCase="true" expand="true"/>

    </analyzer>         

    </fieldType>

 

Relevant section of Solr config:

 

    <requestHandler name="/select" class="solr.SearchHandler">

    <!-- default values for query parameters can be specified, these

         will be overridden by parameters in the request

      -->

     <lst name="defaults">

       <str name="echoParams">explicit</str>

       <int name="rows">100</int>

       <str name="df">ContentSearch</str>

     <bool name="hl">true</bool>

    <str name="hl.fl">Content</str>

    <str name="f.Content.hl.fragsize">150</str>

      <str name="f.Content.hl.snippets">40</str>

     </lst>

    </requestHandler>

    <searchComponent class="solr.HighlightComponent" name="highlight">

    <highlighting>

    <!-- Configure the standard fragmenter -->

    <!-- This could most likely be commented out in the "default" case -->

    <fragmenter name="gap" 

                default="true"

                class="solr.highlight.GapFragmenter">

      <lst name="defaults">

        <int name="hl.fragsize">100</int>

      </lst>

    </fragmenter>

    

    <!-- A regular-expression-based fragmenter 

         (for sentence extraction) 

      -->

    <fragmenter name="regex" 

                class="solr.highlight.RegexFragmenter">

      <lst name="defaults">

        <!-- slightly smaller fragsizes work better because of slop -->

        <int name="hl.fragsize">70</int>

        <!-- allow 50% slop on fragment sizes -->

        <float name="hl.regex.slop">0.5</float>

        <!-- a basic sentence pattern -->

        <str name="hl.regex.pattern">[-\w ,/\n\&quot;&apos;]{20,200}</str>

      </lst>

    </fragmenter>

 

Has anyone experienced this kind of behaviour before? Need some direction
for troubleshooting.

 

Soumya.