In OpenAIRE/oai_datacite export, include user's partial Date of Collection

Overview of the Feature Request

The OpenAIRE/oai_datacite export should include Date of Collection entries even when the user has not provided both a start and end date, using "null" for the missing value, as the DataCite/Datacite export does. Currently, the OpenAIRE/oai_datacite export doens't include the user's Date of Collection when either the start or end date is missing.

This issue is part of a larger effort to align both metadata exports, described in https://github.com/IQSS/dataverse/issues/11916 and https://github.com/IQSS/dataverse/issues/12281.

What kind of user is the feature intended for?

API User, Superuser, and Sysadmin

What inspired the request?

This is part of a larger effort to align the OpenAIRE/oai_datacite and DataCite/Datacite metadata exports. There is more context at https://github.com/IQSS/dataverse/issues/11916 and https://github.com/IQSS/dataverse/issues/12281.

What existing behavior do you want changed?

Currently, when the user adds only a start or end date in the Citation metadata block's Date of Collection block, the DataCite/Datacite export includes a date property with dateType="Collected", using "null" for the missing value. For example:

<date
    dateType="Collected">2000-08-01/null
</date>
<date
    dateType="Collected">null/2000-09-01
</date>

The OpenAIRE/oai_datacite export omits the Date of Collection entries entirely when the user adds only a start date or only an end date.

The OpenAIRE/oai_datacite export should be changed to include partial Date of Collection entries in the same way that the DataCite/Datacite export does.

Any open or closed issues related to this feature request?

• https://github.com/IQSS/dataverse/issues/11916
• https://github.com/IQSS/dataverse/issues/12281

Start by locating the OpenAIRE/oai_datacite and DataCite/Datacite export implementations and comparing how each handles Citation metadata Date of Collection values. Verify the existing partial-date behavior, then ensure the OpenAIRE export emits the corresponding null-ended XML entries and add or update coverage for start-only and end-only dates.