fix: correctly set "multiValued" property in Solr schema for deeply nested fields

[vera]

What this PR does / why we need it:

This PR fixes a bug in the /api/admin/index/solr/schema endpoint reported in #9200. The multiValued property was not set correctly for some deeply nested metadata fields, causing indexing errors:

org.apache.solr.common.SolrException: ERROR: [doc=dataset_1479] multiple values encountered for non multiValued field

This is because the code only checked for whether the direct parent of a metadata field is multi-valued to see whether a child metadata field must be declared as multi-valued in the Solr schema. However, all ancestor fields (parents, grandparents, etc.) need to be checked. This PR updates the code to handle deeper metadata nesting properly.

Which issue(s) this PR closes:

This is related to #9200, but doesn't close the issue, because it also describes UI issues related to deeply nested fields, but it's a fix of the Solr schema bug described there.

Special notes for your reviewer:

/

Suggestions on how to test this:

1. Upload TSV metadata block file e.g. nested_compound_test2.csv (had to rename to CSV to upload here)
2. Activate metadata block
3. Use /api/admin/index/solr/schema to update Solr's schema.xml
4. Reload Solr

(see https://guides.dataverse.org/en/latest/admin/metadatacustomization.html#updating-the-solr-schema)

5. Upload dataset as JSON e.g. nested_compound_test2.json
6. Confirm the dataset indexes without errors

Does this PR introduce a user interface change? If mockups are available, please link/include them here:

/

Is there a release notes update needed for this change?:

/

Additional documentation:

/

[coveralls]

coverage: 22.754% (+0.06%) from 22.693%
when pulling a236d5c on vera:fix/9200-allowmultiples-for-deep-nesting
into 3352bb7 on IQSS:develop.

[pdurbin]

Before switching to this branch, I'm just adding a some detail of the errors one sees on the develop branch when trying to create a dataset using the JSON and TSV above:

dev_dataverse> request: http://solr:8983/solr/collection1
dev_dataverse> Remote error message: ERROR: [doc=dataset_3_draft] multiple values encountered for non multiValued field identifier_type2: [ORCID, ORCID]
...
dev_solr> 2025-01-31 16:43:46.984 ERROR (qtp1331270134-27) [c: s: r: x:collection1 t:null-27] o.a.s.h.RequestHandlerBase Client exception => org.apache.solr.common.SolrException: ERROR: [doc=dataset_3_draft] multiple values encountered for non multiValued field identifier_type2: [ORCID, ORCID]

Also, I don't think this will surprise anyone, but the JSF UI does not support deeply nested fields. It's completely out of scope to fix this in JSF. It looks like this when you click "create dataset":

[pdurbin]

Works great. I added a release note. Approved.

Here are the fields that were added when I updated the Solr schema:

328a329,331
>     <field name="identifier2" type="text_en" multiValued="true" stored="true" indexed="true"/>
>     <field name="identifier_text2" type="text_en" multiValued="true" stored="true" indexed="true"/>
>     <field name="identifier_type2" type="text_en" multiValued="true" stored="true" indexed="true"/>
349a353
>     <field name="person2" type="text_en" multiValued="true" stored="true" indexed="true"/>
570a575,577
>     <copyField source="identifier2" dest="_text_" maxChars="3000"/>
>     <copyField source="identifier_text2" dest="_text_" maxChars="3000"/>
>     <copyField source="identifier_type2" dest="_text_" maxChars="3000"/>
591a599
>     <copyField source="person2" dest="_text_" maxChars="3000"/>

I also made this related PR:

• how to load metadata blocks and adjust Solr in Docker #11204

[ofahimIQSS]

PR looking great. I followed the testing steps and did further regression testing. No issues found. Release snippet looks good as well.

Server log attached
server.log --- Testing PR 11136.txt