Remap oai_dc fields dc:type, dc:date, and dc:rights #8129.

The `oai_dc` export and harvesting format has had the following fields remapped:

- dc:type was mapped to the field "Kind of Data". Now it is hard-coded to the word "Dataset".
- dc:date was mapped to the field "Production Date" when available and otherwise to "Publication Date". Now it is mapped only to the field "Publication Date".
- dc:rights was not mapped to anything. Now it is mapped (when available) to terms of use, restrictions, and license.

doc/release-notes/8129-harvesting.md

@@ -0,0 +1,11 @@
+### Remap oai_dc export and harvesting format fields: dc:type, dc:date, and dc:rights
+
+The `oai_dc` export and harvesting format has had the following fields remapped:
+
+- dc:type was mapped to the field "Kind of Data". Now it is hard-coded to the word "Dataset".
+- dc:date was mapped to the field "Production Date" when available and otherwise to "Publication Date". Now it is mapped only to the field "Publication Date".
+- dc:rights was not mapped to anything. Now it is mapped (when available) to terms of use, restrictions, and license.
+
+As these are backward incompatible changes, they have been noted in the [API changelog](https://guides.dataverse.org/en/latest/api/changelog.html).
+
+For more information, please see issue #8129.

doc/sphinx-guides/source/api/changelog.rst

@@ -7,6 +7,15 @@ This API changelog is experimental and we would love feedback on its usefulness.
     :local:
     :depth: 1
 
+v6.4
+----
+
+- For the ``oai_dc`` metadata export and harvesting (OAI-PMH) format:
+
+  - dc:type was mapped to the field "Kind of Data". Now it is hard-coded to the word "Dataset".
+  - dc:date was mapped to the field "Production Date" when available and otherwise to "Publication Date". Now it is mapped only to the field "Publication Date".
+  - dc:rights was not mapped to anything. Now it is mapped (when available) to terms of use, restrictions, and license.
+
 v6.3
 ----
 

src/main/java/edu/harvard/iq/dataverse/export/dublincore/DublinCoreExportUtil.java

@@ -176,21 +176,55 @@ private static void createOAIDC(XMLStreamWriter xmlw, DatasetDTO datasetDto, Str
 
         writeFullElementList(xmlw, dcFlavor+":"+"language", dto2PrimitiveList(version, DatasetFieldConstant.language));        
 
-        String date = dto2Primitive(version, DatasetFieldConstant.productionDate);
-        if (date == null) {
-            date = datasetDto.getPublicationDate();
-        }
-        writeFullElement(xmlw, dcFlavor+":"+"date", date);  
+        /**
+         * dc:date. "I suggest changing the Dataverse / DC Element (oai_dc)
+         * mapping, so that dc:date is mapped with Publication Date. This is
+         * also in line with citation recommendations. The publication date is
+         * the preferred date when citing research data; see, e.g., page 12 in
+         * The Tromsø Recommendations for Citation of Research Data in
+         * Linguistics; https://doi.org/10.15497/rda00040 ." --
+         * https://github.com/IQSS/dataverse/issues/8129
+         */
+        writeFullElement(xmlw, dcFlavor+":"+"date", datasetDto.getPublicationDate());
 
         writeFullElement(xmlw, dcFlavor+":"+"contributor", dto2Primitive(version, DatasetFieldConstant.depositor));  
 
         writeContributorElement(xmlw, version, dcFlavor);
 
         writeFullElementList(xmlw, dcFlavor+":"+"relation", dto2PrimitiveList(version, DatasetFieldConstant.relatedDatasets));
 
-        writeFullElementList(xmlw, dcFlavor+":"+"type", dto2PrimitiveList(version, DatasetFieldConstant.kindOfData));
+        /**
+         * dc:type. "Dublin Core (see
+         * https://www.dublincore.org/specifications/dublin-core/dcmi-terms/#http://purl.org/dc/terms/type
+         * ) recommends “to use a controlled vocabulary such as the DCMI Type
+         * Vocabulary” for dc:type." So we hard-coded it to "Dataset". See
+         * https://github.com/IQSS/dataverse/issues/8129
+         */
+        writeFullElement(xmlw, dcFlavor+":"+"type", "Dataset");
 
         writeFullElementList(xmlw, dcFlavor+":"+"source", dto2PrimitiveList(version, DatasetFieldConstant.dataSources));
+
+        /**
+         * dc:rights. As stated in https://github.com/IQSS/dataverse/issues/8129
+         * "A correct value in this field would enable BASE to indicate the
+         * degree of Open Access (see more information at
+         * https://www.base-search.net/about/en/faq_oai.php#dc-rights ). For
+         * datasets without access restriction, the dc:rights field could look
+         * like this: info:eu-repo/semantics/openAccess (see more information at
+         * https://guidelines.openaire.eu/en/latest/data/field_rights.html#rightsuri-ma)
+         * ."
+         *
+         * Instead of a single instance of dc:rights, we are including multiple.
+         * We borrow logic from the `createDC` (dcterms) method but we are using
+         * only dc:rights rather than also using dc:license because dc:license
+         * is not one of the 15 fields defined by Simple Dublin Core.
+         */
+        LicenseDTO licDTO = version.getLicense();
+        if(licDTO != null) {
+            writeFullElement(xmlw, dcFlavor+":"+"rights", licDTO.getName());
+        }
+        writeFullElement(xmlw, dcFlavor+":"+"rights", version.getTermsOfUse());
+        writeFullElement(xmlw, dcFlavor+":"+"rights", version.getRestrictions());
 
 
     }