Sitecore 9 Indexing : Solr Pattern Tokenizer not Working - solr

Question

I'm new with this combination sitecore and solr stuff.. I've a little issue with the pattern tokenizer which is not working.. I'm following this documentation
Solr :
https://lucene.apache.org/solr/guide/6_6/tokenizers.html#Tokenizers-RegularExpressionPatternTokenizer)
Sitecore 9 Solr :
https://doc.sitecore.net/sitecore_experience_platform/setting_up_and_maintaining/search_and_indexing/using_solr_field_name_resolution
When I do the indexing, my field value is : a,b,c and I expected on solr it will be ["a","b","c"] but it contains ["a,b,c"]
This is my Sitecore Config
<fieldMap>
<typeMatches hint="raw:AddTypeMatch">
<typeMatch type="System.Collections.Generic.List`1[System.String]" typeName="commaDelimitedCollection" fieldNameFormat="{0}_cd"
multiValued="true" settingType="Sitecore.ContentSearch.SolrProvider.SolrSearchFieldConfiguration, Sitecore.ContentSearch.SolrProvider"/>
</typeMatches>
<fieldNames hint="raw:AddFieldByFieldName">
<field fieldName="Keywords" returnType="commaDelimitedCollection"/>
</fieldNames>
</fieldMap>
This is my Solr Schema
<fieldType name="commaDelimited" class="solr.TextField" multiValued="true">
<analyzer>
<tokenizer class="solr.PatternTokenizerFactory" pattern="\s*,\s*"/>
</analyzer>
</fieldType>
<dynamicField name="*_cd" type="commaDelimited" multiValued="true" indexed="true" stored="true"/>
Any idea what's wrong with my configuration above?
Thanks

Answer 1

Not sure if I get the full picture here. Maybe your approach is perfectly valid, but I don't think I've seen that one before. Instead of defining a new type, you could reuse the *_sm (multiValued string) and perform the splitting of the string at index time on the Sitecore side. Usually you don't need more field types than the ones provided by sitecore and it's typically easier to maintain all the code in your VS solution instead of depending on additional Solr config. (In Sitecore 9 you can deploy your Solr managed schema from the control panel though.)
A simple computed field field can look like this:
<fields hint="raw:AddComputedIndexField">
<field fieldName="keywords" returnType="stringCollection">
Your.Name.Space.YourComputedFieldClass, YourAssembly
</field>
</fields>
And a class implementation could look something like this:
public class YourComputedFieldClass : IComputedIndexField
{
public object ComputeFieldValue(IIndexable indexable)
{
var item = indexable as SitecoreIndexableItem;
var fieldValue = item?.Item?["Keywords"]
if (string.IsNullOrWhitespace(fieldValue)) {
return null;
}
return fieldValue.Split(',');
}
public string FieldName { get; set; }
public string ReturnType { get; set; }
}