Crossref deposits fail when surname is missing

[AhemNason]

Describe the problem you would like to solve
There are three issues with Crossref deposits that require some reconfiguration of how we map name metadata to their schema.

1. Crossref requires a surname but this is optional in OJS.
2. The Crossref deposit plugin may write an empty <surname> tag to the export XML, which will lead to a validation error on Crossref's end.
3. We should add support for preferred name via the <alt-name> element.

Describe the solution you'd like

1. we could either swap which field is required on our end, or...when the only field filled out is "given name", just write that to the surname element.
2. remove the empty tags from the XML and deposit them manually.
3. The following is some example XML:

                    <person_name contributor_role="author" sequence="first" language="en">
                        <given_name>Andrew</given_name>
                        <surname>Kerr</surname>
                        <alt-name>Andy Kerr</alt-name>
                    </person_name>

Who is asking for this feature?
Crossref asked specifically about the surname requirement. The other two have come up on the hosting side a number of times.

[AhemNason]

Oh, I should note too that is supported in the schema version we're using 4.3.6. Once Crossref will be adding ROR to their schema in early 2022 (I think), we should probably consider just fully updating the schema we write to in our exports to accommodate.

[NateWr]

I've flagged this as a bug and assigned it to the 3.3.0-9 milestone for the problems with the surname field. The preferred name feature should be split to a new issue and only implemented for a future version.

[NateWr]

we could either swap which field is required on our end

Just a note that we can't/won't do this. "Surnames" are a western thing and "Family Names" (the term we use) do not exist in all languages/cultures.

[NateWr]

I was going to tackle this today but I don't actually know what a solution would be. Given the following author record with no surname:

{
  "givenName": "Andrew"
}

Would it be best for OJS to deposit the following:

<person_name contributor_role="author" sequence="first" language="en">
    <given_name>Andrew</given_name>
</person_name>

Or -- and I know this is evil but it's Crossref's doing -- the following:

<person_name contributor_role="author" sequence="first" language="en">
    <given_name>Andrew</given_name>
    <surname>-</surname>
</person_name>

[AhemNason]

Right, so in the Crossref schema, they made the decision to support single-name deposits as well. But, they just went with the other name field.

<person_name contributor_role="author" sequence="first" language="en">
    <surname>Andrew</surname>
</person_name>

This is facet valid and expected in the schema. I know it seems a little weird, but I suspect it's because of the expected placement of a person's name in like... citations. Surname is usually listed first, so that's likely the logic here. In any event the recommendtions is that if we just have a single given name, we write it to Crossref's schema in the surname field.

[NateWr]

Ok that makes sense, thanks.

[NateWr]

See also #6863

[mpbraendle]

The Crossref schema has an "anonymous" element (as subelement of contributors) that should be used in such a case.

[AhemNason]

Anonymous in the Crossref schema is for an anonymous author, not for situations where one of two name elements is missing.